research paper

Malignancy-associated haemophagocytic lymphohistiocytosis in children and adolescents

Kai Lehmberg,1 Bj€ orn Sprekels,1 Kim 2 E. Nichols, Wilhelm Woessmann,3 Ingo M€ uller,1 Meinolf Suttorp,4 Toralf Bernig,5 Karin Beutel,6 Sebastian F. N. Bode,7 Karim Kentouche,8 Reinhard Kolb,9 Alfred La¨ngler,10 Milen Minkov,11 Freimut H. Schilling,12 Irene Schmid,13 Simon Vieth,14 Stephan Ehl,7 Udo Zur Stadt1 and Gritta E. Janka1 1

Paediatric Haematology and Oncology, Univer-

sity Medical Centre Hamburg Eppendorf, Hamburg, Germany, 2Department of Oncology, St. Jude Children’s Research Hospital, Memphis, Tennessee, USA, 3Paediatric Haematology and Oncology, University Hospital Giessen, Giessen, 4

Paediatric Haematology and Oncology, Univer-

sity Hospital Dresden, Dresden, 5Paediatric Haematology and Oncology, University Hospital Halle, Halle, 6Paediatric Haematology and Oncology, Clinical Centre Schwabing and M€ unchen Rechts der Isar, Technical University Munich, Munich, 7Centre of Chronic Immunodeficiency, University of Freiburg, Freiburg, 8Paediatric Haematology and Oncology, University Hospital Jena, Jena, 9Paediatric Haematology and Oncology, Elisabeth-Hospital Oldenburg,

Summary Haemophagocytic lymphohistiocytosis (HLH) in the context of malignancy is mainly considered a challenge of adult haematology. While this association is also observed in children, little is known regarding inciting factors, appropriate treatment and prognosis. We retrospectively analysed 29 paediatric and adolescent patients for presenting features, type of neoplasm or preceding chemotherapy, treatment and outcome. Haemophagocytic lymphohistiocytosis was considered triggered by the malignancy (M-HLH) in 21 patients, most of whom had T- (n = 12) or B-cell neoplasms (n = 7), with Epstein–Barr virus as a co-trigger in five patients. In eight patients, HLH occurred during chemotherapy (Ch-HLH) for malignancy, mainly acute leukaemias (n = 7); an infectious trigger was found in seven. In Mand Ch-HLH, median overall survival was 1
2 and 0
9 years, and the 6 month survival rates were 67% and 63%, respectively. Seven of 11 deceased M-HLH patients exhibited active malignancy and HLH at the time of death, while only two out of five deceased Ch-HLH patients had evidence of active HLH. To overcome HLH, malignancy- and HLH-directed treatments were administered in the M-HLH cohort; however, it was not possible to determine superiority of one approach over the other. For Ch-HLH, treatment ranged from postponement of chemotherapy to the use of etoposide-containing regimens. Keywords: T-cell lymphoma, Hodgkin lymphoma, anaplastic large cell lymphoma, macrophage activation syndrome, hemophagocytic syndrome.

Oldenburg, 10Gemeinschaftskrankenhaus Herdecke, University of Witten/Herdecke, Herdecke, Germany,

11

Paediatric Haematology and Oncol-

ogy, Rudolfstiftung Hospital Vienna, Vienna, Austria,

12

Paediatric Oncology and Haematology,

Olgahospital, Klinikum Stuttgart, Stuttgart, 13

Dr. von Hauner Children’s Hospital, Ludwig-

Maximilians-University Munich, Munich, and 14

Paediatric Haematology and Oncology, University Hospital Kiel, Kiel, Germany Received 6 December 2014; accepted for publication 9 March 2015 Correspondence: Dr. Kai Lehmberg, Department of Paediatric Haematology and Oncology, University Medical Centre, Martinistrasse 52, Hamburg 20246, Germany. E-mail: [email protected]

ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

First published online 4 May 2015 doi: 10.1111/bjh.13462

K. Lehmberg et al Haemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition typified by clinical features such as fever, organomegaly and cytopenias, associated with a characteristic set of laboratory parameters. Apart from HLH in patients with hereditary defects (e.g. familial HLH (FHL) 2-5, certain albinism syndromes and the x-linked lymphoproliferative syndromes), the spectrum of underlying conditions leading to acquired HLH is broad and includes infections, rheumatic and metabolic disorders and malignancies (Janka & Lehmberg, 2014). Haemophagocytic lymphohistiocytosis in the context of a malignant disease can occur in two settings: First, presentation concomitant with (or even prior to) overt malignant disease, suggesting the hyperinflammation is triggered by the neoplasm. Second, presentation during chemotherapy – frequently occurs in patients that have already achieved remission – pointing towards a process related to therapy-induced immune suppression. In the latter cases, triggering infections can often be identified. While hereditary forms of HLH predominantly present at young age, the proportion of HLHpatients with an underlying malignancy is higher in adults (Ramos-Casals et al, 2014). Prospective studies for children and adolescents are lacking and retrospective case series are scarce (Veerakul et al, 2002; Trebo et al, 2005). We retrospectively analysed the largest cohort of children and adolescents published to date, to better elucidate the presenting features, therapy and survival of malignancy-associated HLH. It is the first study to distinguish throughout between malignancy-triggered HLH and HLH during antineoplastic chemotherapy, compare outcome of both groups and analyse the different treatment approaches of malignancy- versus HLH-directed therapy.

Methods Patients with any form of HLH treated at paediatric hospitals in Germany, Austria and Switzerland are reported to a clinical reference centre in Hamburg. The Children’s Hospital of Philadelphia (CHOP) is a treatment centre for HLH. This study was approved by the ethics committees of the Hamburg Chamber of Physicians and CHOP. Through a retrospective survey of the databases of both institutions, we identified patients who had been diagnosed with HLH in the context of malignant disease between 1996 and June 2012. Most children were treated according to protocols from the different malignant disease study groups. Patients with underlying conditions not clearly considered malignant (e.g. Langerhans cell histiocytosis) were not included. We collected information on clinical and laboratory findings, treatment and outcome of patients up to 20 years of age. The diagnosis of HLH was established according to the HLH-2004 criteria, which requires that at least five out of eight of the following need to be fulfilled (Henter et al, 2007): (i) fever, (ii) splenomegaly, (iii) cytopenia of at least 540

two cell lines (haemoglobin ≤90 g/l, platelet count ≤100 9 109/l, neutrophil count ≤1 9 109/l), (iv) hypofibrinogenaemia (≤1
5 g/l) or hypertriglyceridaemia [≥3 lmol/l (265 mg/dl)], (v) hyperferritinaemia (≥500 lg/l), (vi) increased level of soluble CD25 [sCD25 (sIL2RA), ≥2400 u/ ml], (vii) evidence of haemophagocytosis, and (viii) decreased or absent Natural Killer (NK)-cell cytotoxicity. Genetic and flow cytometric analyses were performed as described previously (Zur Stadt et al, 2006; Bryceson et al, 2012). Informed consent was obtained from the parents and, if appropriate, the patients. For descriptive analyses, proportions were determined. Survival curves were plotted using the Kaplan–Meier method. Differences of survival were analysed with the log rank test. For survival rates, a short 6 month interval was chosen to reflect the acuity of HLH. All calculations were performed with PREDICTIVE ANALYTICS SOFTWARE (PASW) Statistics 18  (IBM, Armonk, NY, USA).

Results Inclusion and exclusion We identified 57 patients who were reported with suspected HLH in the context of malignant disease. The prevalence of malignancy in reported paediatric and adolescent cases of suspected HLH was 8
4%. The following patients were excluded from the study: 16 patients not fulfilling the HLH2004 diagnostic criteria, one patient in whom the suspected diagnosis of malignancy could not be confirmed, four patients in whom HLH developed following haematopoietic stem cell transplantation (HSCT) for a malignant condition, one patient in whom HLH occurred years after the malignant disease without evidence of relapse, two patients where HLH in the context of malignancy had been reported in detail previously (Sovinz et al, 2008; Lackner et al, 2013) and four patients with insufficient clinical data. Finally, 29 patients were included in the analysis.

General data, HLH diagnostic parameters, and hereditary defects In 21 patients, HLH presented at cancer onset (n = 17) or was diagnosed 42–153 days prior to the identification of the malignancy (n = 4) (Table I). In the latter cases, initial presence of lymphoma was either later proven by pathology review or must be assumed in retrospect. We refer to this entity as malignancy-triggered HLH (M-HLH). In eight patients, HLH occurred during chemotherapeutic treatment, here referred to as Ch-HLH, 67 – 532 days (median 220 days) after diagnosis of the neoplasm. The median age at onset was 12
0 years (range 1–20) for M-HLH and 5
5 years for Ch-HLH (range 0–18). M-HLH predominantly affected boys (male:female ratio 2
6), while the distribution of sexes in Ch-HLH patients was even. ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

HLH in Paediatric Malignancy Table I. Characteristics of malignancies and triggers.

UPN

Gender

Age at HLH (years)

Malignancy

Specified

Onset of HLH with regard to malignancy

Infectious trigger of HLH

Initially Initially Initially Initially Initially Initially, relapse initially Initially Initially Initially, relapse Initially Initially* Initially

– – – – – – – – EBV (6 9 104/ml blood, NHL EBER-negative) – – – EBV (blood + bone marrow positive, not done in HL) EBV (after HL, 2
4 9 103/ml blood at HLH reactivation) –

Malignancy-triggered HLH 1 7 11 13 19 4 10 15 3 14 17 36 2

m m m f m m m m m m m f m

16 7 4 14 4 12 12 15 2 18 15 10 12

ALCL ALCL ALCL ALCL ALCL T-NHL T-NHL T-NHL T-NHL T-NHL T-NHL T-ALL HL

8

m

11

HL

20

m

9

HL

9 40 12

m m f

1 20 18

DLBCL DLBCL LPS

18 5 6

f m m

16 3 11

ALL MDS MDS

B-precursor Monosomy 7

Initially Initially Initially

EBV (4 9 103/ml blood, DLBCL EBER-positive) – EBV (2
2 9 105/ml blood, skin infiltrate EBER-positive) – Leishmaniasis –

Cortical B-precursor Classical, stage IV M2 B-precursor, KMT2A-positive

In remission In remission Before remission In remission Before remission

E. coli prior to HLH E. coli prior to HLH, HSV EBV HHV6, later HSV1 –

In remission In remission In remission

Aspergillus, later VZV Adenovirus CMV

Peripheral Cutaneous, cd-positive Peripheral Lymphoblastic Not specified Lymphoblastic Lymphoblastic Nodular sclerosing, stage IV Nodular sclerosing, Stage III; FHL5 Lymphocyte predominant, Stage IV T-cell rich

Initially Initially Initially* Initially* Initially*

HLH during chemotherapy 21 22 23 24 25

m m f f m

18 4 7 16 0
5

T-ALL cALL HL AML ALL

26 29 35

m f f

17 0
7 2
2

T-ALL AML ALL

B-precursor

ALCL, anaplastic large cell lymphoma; ALL, acute lymphoblastic leukaemia; AML, acute myeloid leukaemia; CMV, cytomegalovirus; DLBCL, diffuse large B-cell lymphoma; EBER, Epstein-Barr encoded RNA; EBV, Epstein-Barr virus; FHL5, familial haemophagocytic lymphohistiocytosis type 5; HHV, human herpes virus; HL, Hodgkin lymphoma; HLH, haemophagocytic lymphohistiocytosis; HSV, herpes simplex virus; KMT2A, lysine (K)-specific methyltransferase 2A gene, previously termed MLL (mixed-lineage leukaemia gene); LPS, lymphoproliferative disease; NHL, non-Hodgkin lymphoma; MDS, myelodysplastic syndrome; sCD25, soluble CD25; VZV, varizella zoster virus; UPN, unique patient number. In patients marked with an asterisk *, HLH was diagnosed and treated before the diagnosis of malignant disease.

Cytopenias were particulary pronounced in Ch-HLH patients (Table SI with detailed laboratory data on each patient). Elevations of sCD25 and ferritin as hallmarks of HLH were substantial in both cohorts; 95% of patients met the respective HLH-2004 criterion (Henter et al, 2007). Functional flow cytometric NK cell analyses were performed in seven patients, genetic studies in 12 patients (Table SI). In Patient 8, with Hodgkin lymphoma (previously reported by Pagel et al, 2012), an NK-cell degranulation defect in the CD107 assay and a biallelic mutation of ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

STXBP2 were identified, establishing the diagnosis of FHL5. Slightly reduced NK-cell degranulation and a heterozygous mutation of STX11 were documented in Patient 15 with peripheral T-cell lymphoma.

Distribution of malignancies M-HLH (n = 21): Most patients in the M-HLH cohort had a T-cell malignancy (57%, n = 12), the majority of which were mature T-cell lymphomas (n = 8), mainly anaplastic large 541

K. Lehmberg et al cell lymphoma (n = 5), less frequently lymphoblastic lymphomas (n = 3). The group of B-lineage neoplasias (33%, n = 7) mainly consisted of Hodgkin lymphoma (n = 3) and diffuse large B-cell lymphoma (DLBCL, n = 2). Myelodysplastic syndrome (MDS) was diagnosed in 10% (n = 2) (Table I). Ch-HLH (n = 8): HLH during chemotherapy occurred most frequently in the context of anti-leukaemic treatment, i.e. lymphoblastic (n = 5) and myeloid leukaemias (n = 2), including induction (n = 2), consolidation (n = 2) and maintenance (n = 3) therapies.

Infectious triggers An infectious agent was identified in six out of 21 M-HLH (29%). In two patients (Patients 9 and 12) with B-lineage neoplasms, Epstein–Barr encoded RNA (EBER) was found in the tumour cells. Epstein–Barr virus (EBV)-DNA was detectable at variable copy numbers (2
4 9 103 2
2 9 105/ml) in the blood of patients 2, 3, 8, 9 and 12. In seven out eight Ch-HLH patients (88%), a microbiological trigger could be identified, mostly viruses including herpes simplex virus (HSV), EBV, varizella zoster virus (VZV) and cytomegalovirus (CMV). In two patients, HLH developed after an E. coli septicaemia, however after clearance of the pathogen; another patient had an Aspergillus infection (Table I).

Treatment and outcome Overview M-HLH patients (n = 21): In the M-HLH cohort (see Table II and Fig 1), median overall survival was 1
2 years and the 6 month overall survival rate was 67%. In total, 11 out of 21 patients died during the observation period. It was not always possible to fully differentiate whether HLH or the neoplasm was the leading cause of death. However, seven patients had active HLH and malignancy at death, particulary in the T-cell malignancy group. In ten patients, first-line treatment consisted of malignancy-directed protocols, all of which per se contain agents known to be active in HLH as well (corticosteroids n = 10, etoposide n = 8, cyclophosphamide n = 2). Some patients later received an HLH-directed second-line (n = 3) therapy or a combined regimen (n = 1). HLH-directed first-line therapies were chosen in 11 patients (in four of whom malignancy had not been identified initially), followed by a malignancy-directed (n = 7) or combined treatment scheme (n = 2). M-HLH with anaplastic large cell lymphoma (ALCL) (n = 5; 2 overall deaths, 1 with active HLH and ALCL): Four patients (Patients 1, 7, 11, 19) achieved remission or partial remission of HLH with a lymphoma-directed protocol. HSCT was required in three of these four patients (Patients1, 11, 19) for persistent or relapsed lymphoma, one of whom later died (Patient 1). One patient (Patient 13) had a rapidly fatal course of HLH and did not respond to any type of therapy, including basiliximab and alemtuzumab. 542

M-HLH with T-cell non-Hodgkin lymphoma (T-NHL) other than ALCL (n = 7; 6 overall deaths, 4 with active HLH and lymphoma, 2 with active lymhpoma): Malignancydirected therapy was applied upfront in three patients (Patients 3, 4, 14), resulting in good response of HLH in two patients. However, both later relapsed with HLH and lymphoma. Four patients (Patients 10, 15, 17, 36) initially received HLH-directed therapy with variable response. Two patients (Patients 3, 10) never achieved remission from HLH and NHL with any type of therapy, including rituximab for EBV in Patient three. Only one patient (Patient 15) is alive after HSCT for peripheral T-cell lymphoma. M-HLH with B-lineage malignancies (n = 7; 2 deaths, both with active HLH and malignancy): Both patients with DLBCL (Patients 9, 40) were initially diagnosed only with HLH and treated accordingly, but achieved only a poor response of HLH. After diagnosis of lymphoma, malignancy-directed treatment was initiated without success and both patients died. All other patients with B-lineage malignancies survived. Two patients (Patients 2, 8) with Hodgkin lymphoma responded to a malignancy-directed regimen. A third patient (Patient 20) exhibited poor response with reactivation of HLH after each cycle of malignancy-directed therapy, which prompted a combined HLH- and malignancy-directed approach, including rituximab and high-dose chemotherapy with autologous stem cell rescue. One patient with malignant lymphoproliferative syndrome (Patient 12) and one with acute lymphoblastic leukaemia (ALL, Patient 18) only partially responded to HLH-directed treatment, and therefore malignancy-directed elements were successfully added. Rituximab was administered for CD20-positivity of the neoplasm in Patients 20 and 40, for EBV in Patient 12 and for both in Patient 9. M-HLH with myelodysplastic syndrome (MDS, n = 2; 1 death unrelated to HLH or MDS): Both patients responded to HLH-directed therapy. Visceral leishmania had been diagnosed in Patient 5, based on a high titre before the diagnosis of MDS so that liposomal amphotericin B was administered, as reported previously (Bode et al, 2014). Both patients underwent HSCT; Patient 5 survived but Patient 6 died due to transplant-related mortality. Ch-HLH (n = 8; 5 deaths, 2 with active HLH): Median overall survival was 0
9 years and the 6-month survival rate was 63% (Table III, Fig 1). Two patients died during the acute HLH episode (Patients 21, 23), however three additional patients died later due to leukaemia relapse or complications (Patients 25, 26, 29). In all patients, further chemotherapy was postponed at diagnosis of HLH. HLHdirected treatment was given first or second line in seven patients, ranging from steroids only (n = 3; Patients 23, 29, 35) to VP16 (etoposide)-containing regimens (n = 4; Patients 21, 22, 24, 26), with addition of an anti-CD25 antibody in Patient 24. Anti-viral (acyclovir, cidofovir, foscarnet, ribavirin) or anti-fungal therapy (voriconazole, liposomal amphoª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

ALCL

ALCL

ALCL

ALCL

ALCL

T-NHL

T-NHL

T-NHL

T-NHL

T-NHL

7

11

13

19

4

10

15

3

14

Malignancy

1

UPN

ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

MD

MD

HLH-D

HLH-D

MD

HLH-D

MD

MD

MD

MD

First-line treatment

Pred, CPM, VCR

Dex, CPM; then Pred, VCR, DNR, ASP

CSA, Dex; then VP16, IVIG

Dex, VP16

Dex, MTX, VP16, IFO, VP16, AraC

Dex, CPM prephase; then MTX, VP16, IFO, VP16, AraC Dex, CPM prephase; then MTX, VP16, IFO, VP16, AraC Dex, CPM prephase; then MTX, VP16, IFO, VP16, AraC Dex, CPM prephase; then VDS, AraC, VP16 Dex, VP16

Drugs of first-line treatment

Good, relapse

Poor

Partial

Poor

Good, relapse

Partial

Poor

Partial

Good

Good

Response of HLH to first line-treatment

–

–

–

–

HLH-D

HLH-D

MD

MD

–

MD

Alem, Ritux (for EBV), Basil, Dex, CSA; VP16; RTx Dex, CSA, VP16

Dex, CPM prephase; MTX, VP16, IFO, VP16, AraC Dex, MTX, AraC, VP16, Ifo

Dex, CPM prephase; MTX, VP16, IFO, VP16, AraC –

Basil, IVIG, Pred, VP16, Alem

–

–

HLH-D

Drugs of second-line treatment

Second line treatment

Table II. Treatment and outcome of malignancy-triggered HLH (M-HLH).

Partial

Poor

Good

Poor

–

Good

Poor

–

–

–

Response to second -line treatment

Died

Died

Surv

Died

Surv

Surv

Died

Surv

Surv

Surv

Outcome of HLH

95

Died

Died

Surv

–

86

Died

103

Died

Surv

–

NA

Died

Surv

Surv

Died

General outcome

8

–

–

NA

Time from HLH until death [days]

HLH, T-NHL

HLH, T-NHL

–

HLH, T-NHL

T-NHL

–

HLH, ALCL

–

–

PostHSCT

Cause of death

HLH, possible NHL > MD-therapy > response > relapse > HLH-D therapy > partial response > death

–

–

Heterozygous STX11 mutation, HSCT for lymphoma Never achieved remission from NHL or HLH

2x remission HLH/ T-NHL by MD therapy; HSCT, 2. relapse, death Never achieved remission from NHL or HLH 2
4

–

–

Later HSCT for ALCL relapse

Rapidly fatal course of HLH

–

15

Recurrent HLH between chemo cycles. HSCT for persistent ALCL

Later HSCT for ALCL relapse

Remarks

1
6

11

–

Follow up [years]

HLH in Paediatric Malignancy

543

544

MDS

6

HLH-D

HLH-D

HLH-D

HLH-D

HLH-D

HLH-D

MD

MD

MD

HLH-D

HLH-D

L-AmB; Dex, CSA, VP16 Dex, CSA, VP16

Dex, VP16; later +CSA

Ritux, Dex, VP16, CSA

Dex, VP16

Dex, VP16, CSA

Pred, Dox, VP16, VCR Pred, Dox, VP16, VCR Pred, Dox, VP16, VCR

Dex, VP16

Dex, VP16

Drugs of first-line treatment

Good

Good

Partial

Partial

Poor

Poor

Poor

Good

Good

Good, relapse

Partial

Response of HLH to first line-treatment

–

–

CSA, Dex, VCR, DNR, ASP – –

– –

Dex, Ritux, MTX, CPM

HLH-D MD

MD

MD, HLH-D

MD

Ritux, CSA, Dex, VP16, Ifo; later Dex, Ara-C, CDDP Ritux, Acyclovir; then Pred, CPM, Dox, VCR Ritux, CPM

–

–

HLH-D MD

Pred, DNR, ASP; then Alem

Pred, DNR, VCR, ASP

Drugs of second-line treatment

MD

MD

Second line treatment

–

–

Good

Good

Poor

Poor

Slow

–

Surv

Surv

Surv

Surv

Died

Died

Surv

Surv

Surv

Died

Poor

–

Died

Outcome of HLH

Partial

Response to second -line treatment

NA

–

Died

Surv

Surv

Surv

–

–

Died

129

Died

Surv

–

80

Surv

Surv

Died

Died

General outcome

–

–

239

40

Time from HLH until death [days]

GvHD

–

–

–

HLH DLBCL

HLH, DLBCL

–

–

–

HLH, T-NHL

T-NHL

Cause of death

–

5
9

1
4

3
5

Later HSCT for MDS

HLH* > HLH-D therapy > diagnosis of DLBCL > refractory HLH* > HLH-D therapy > poor response > dx of DLBCL > MOF HLH* > HLH-D therapy > diagnosis of malignant LPS > MD therapy Multiple complications during HLH and ALL induction therapy Later HSCT for MDS

–

–

Recurrent episodes between chemo cycles

Ulcer. colitis, HLH > HLH-D therapy > dx of NHL > MD therapy > death HLH* > HLH-D therapy > relapse > dx of T-ALL > MD therapy > death HLH relapse > dx of FHL5 > HSCT

Remarks

2
4

4
6

3
5

–

–

Follow up [years]

ALCL, anaplastic large cell lymphoma; ALL, acute lymphoblastic leukaemia; DLBCL, diffuse large B-cell lymphoma; HL, Hodgkin lymphoma; FHL5, familial haemophagocytic lymphohistiocytosis type 5; HLH, haemophagocytic lymphohistiocytosis; HLH-D, HLH-directed treatment; HSCT, haematopoietic stem cell transplantation; LPD, lymphoproliferative disease; NHL, non-Hodgkin lymphoma; MD, malignancy directed treatment; MDS, myelodysplastic syndrome; RTx, radiotherapy; UPN, unique patient number; m, male; f, female; GvHD, graft-versus-host disease; NA, not available; dx, diagnosis. Drugs: Alem, alemtuzumab; AraC, cytarabine; ASP, asparaginase; Basil, basiliximab; CDDP, Cisplatin, CPM, cyclophosphamide; CSA, ciclosporin; Dex, dexamethasone; DNR, daunorubicin; Dox, doxorubicin; IFO, ifosfamide; IVIG, intravenous immunoglobulins; L-Amb, liposomal Amphotericin B; 6MP, 6’-mercaptopurine; MTX, methotrexate; Pred, prednisone; Ritux, rituximab; VCR, vincristine; VDS, vindesine; VP16, etoposide. In patients marked with an asterisk *, HLH was diagnosed and treated before the diagnosis of malignant disease. Presence of the neoplasm at HLH onset was proven by retrospective pathology review (P36, P40) or must be assumed (P9, P12). The time from diagnosis of HLH until identification of the malignancy was 42 days (P9), 99 d (P12), 153 d (P36), and 121 d (P40).

MDS

5

LPD

12

ALL

DLBCL

40

18

DLBCL

HL

20

9

HL

2

T-ALL

36

HL

T-NHL

17

8

Malignancy

UPN

First-line treatment

Table II. (Continued)

K. Lehmberg et al

ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

HLH in Paediatric Malignancy 1·0

Cumulative survival

0·8

0·6

0·4

0·2

0·0 0

5

10

15

20

Time [years]

Fig 1. Kaplan–Meier estimation of overall survival of patients with malignancy-triggered haemophagocytic lymphohistiocytosis (HLH) (solid line) and HLH during chemotherapy (dashed line). There was no difference of survival between both groups (P = 0
55)

tericin B) was administered in five patients (Patients 22, 24, 26, 29, 35).

Discussion Awareness of an underlying malignancy in adult patients with HLH is high, given that 48% of published adult cases are triggered by a neoplasm (Ramos-Casals et al, 2014). In contrast, paediatricians are trained to suspect an underlying genetic defect, since these patients predominantly present at a younger age. However, the present analysis demonstrates that malignant triggers are not uncommon in paediatric patients with HLH (prevalence 8
4%). The analysis probably even underestimates the prevalence, because some patients with immune dysregulation fulfilling the HLH-2004 criteria in the context of a malignant condition may not have been reported. A group from Thailand found a malignant trigger in 48% of paediatric patients (Veerakul et al, 2002), however the study was restricted to acquired HLH. This report confirms the association of M-HLH with Tcell malignancies (57% of M-HLH) that has been suggested by prior series (Veerakul et al, 2002). So far, the reasons for this can only be speculated. Serum analysis of patients and in vitro analysis of an ALCL cell line from a paediatric patient with features of HLH suggested that cytokine production (including interferon-c and interleukin 6) by the malignant cells play a key role in the clinical picture (Al-Hashmi et al, 2001; Siebert et al, 2007; Mellgren et al, 2012). Elevation of sIL2R (sCD25), which is a hallmark of HLH, has been reported to be a response marker in ALCL (Janik et al, 2004). ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

B-cell malignancies including Hodgkin lymphoma can also elicit HLH. The high prevalence of EBV in Hodgkin lymphoma associated HLH (two out of three patients) is in line with the literature (prevalence 86–94%) (Menard et al, 2008; Chang et al, 2009). A peculiar exception from the confinement to the haematological malignancies is HLH in primary mediastinal germ cell tumours (Nichols et al, 1990; Urban et al, 2003). Other solid tumours are only very occasionally reported (Ramos-Casals et al, 2014). Of note, HLH during chemotherapy for leukaemia is not restricted to intensive treatment phases and can be equally fatal in maintenance therapy, compatible with previous reports (Trebo et al, 2005). Even though only one patient with definite hereditary HLH was identified in this cohort, the genetic and functional studies were not sufficient to exclude a contribution of hypomorphic mutations in HLH-related genes in patients with M-HLH. Hodgkin lymphoma has been described in different forms of hereditary HLH (Lorenzi et al, 2013; Machaczka et al, 2013; Nagai et al, 2013). Existing evidence suggests hypomorphic biallelic mutations in PRF1 (FHL2) can confer predisposition to haematological malignancies (Clementi et al, 2005; Cannella et al, 2007; Chia et al, 2009). An analysis of patients with solid tumours, such as colorectal cancer and ovarian carcinoma, did not show a correlation to the PRF1 genotype (Trapani et al, 2013). In 91 patients with Xlinked lymphoproliferative syndrome type 1, a disorder associated with aggressive HLH at primary EBV infection, 24% had had a malignant lymphoproliferative disorder, usually Blineage NHL (Booth et al, 2011). EBV-susceptibility and a propensity to lymphoma has been found in primary immunodeficiences caused by mutations in magnesium transporter 1 (MAGT1, resulting in X-linked immunodeficiency with Magnesium defect, EBV infection and Neoplasia, XMEN) and interleukin-2-inducible T-cell kinase (ITK) (Ghosh et al, 2014; Ravell et al, 2014). In the latter, occasional occurrence of at least partial HLH has also been reported. We could not find a mutation in either of these genes In the two male patients with EBV-associated M-HLH for whom genetic material was available. It is a matter of debate if the widely used HLH-2004 criteria for the definition of HLH are appropriate in malignant conditions, as some features are inherent to the malignancy itself, e.g. cytopenia and organomegaly. It was not surprising that cytopenia was profound in Ch-HLH patients during intensive chemotherapy, as these episodes frequently commenced during post-chemotherapy nadir. Despite a possible contribution of the underlying malignancy or treatment, the current HLH-2004 criteria are frequently used for treatment decisions, justifying the use in the present analysis, despite their limitations. Potential alternatives have thus far not gained wide acceptance (Takahashi et al, 1999). The suggested criterion ‘absence of infection’ (Shimazaki et al, 2000) must be reconsidered as we have observed that EBV is a frequent viral co-trigger in M-HLH 545

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AML

ALL

T-ALL

24

25

26

Maintenance (VCR, Dex, MTX, 6MP)

AraC, Mitox

Maintenance (TG) AraC, DNR, VP16 Pred, VCR, ASP, DNR

Dox, Bleo, Dacti, VBL

Maintenance (MTX, 6MP) CPM, AraC, TG

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Yes

Further chemotherapy postponed

Foscarnet, CMV-antibody

Splenectomy; Dex, VP16 MD therapy postponed only Dex, VP16, L-Amb, Voriconazole, Acyc Pred, Ribavirin, Cidofovir

Dex

Dex, VP16, IVIG Dex, VP16, Acyc, Foscarnet

Firstline HLH-directed treatment

Poor

Good

Good

Good

Partial

Poor

Slow

Poor

Response of HLH to first-linetreatment

Dex

–

Good

–

–

–

Surv

Surv

Surv

Surv

Died

–

–

–

Surv

Surv

–

–

Died

Slow

–

–

Outcome of HLH

Dacli, Dex, Acyc –

Response to second line treatment

Second line HLHdirected treatment

Died

Surv

–

Died

N.A.

N.A.

Died

Surv

– N.A.

Died

Surv

Died

General outcome

10

–

16

Time from HLH until death (days)

Pulmonary haemorrhage at biopsy –

Relapse of ALL

Relapse of ALL

–

HLH, HL

HLH, cerebral haemorrhage –

Cause of death

5
1

–

–

–

5
2

–

1
2

–

Follow up (years)

ALL relapsed later with partial HLH alive in 2nd remission

3 weeks prior E. coli sepsis CPR during HLH > cerebral hypoxaemia Relapse > MD therapy > HLH, EBV encephalopathy > death Later HSCT for AML

Remarks

ALL, acute lymphoblastic leukaemia; AML, acute myeloid leukaemia; CPR, cardiopulmonary resuscitation; HL, Hodgkin lymphoma; HLH, haemophagocytic lymphohistiocytosis; HSCT, haematopoietic stem cell transplantation; MD, malignancy directed treatment; N.A, not applicable; UPN, unique patient number; CMV, cytomegalovirus. Drugs: Acyc, acyclovir; AraC, cytarabine; ASP, asparaginase; Bleo, bleomycin; CPM, cyclophosphamide; Dacli, daclizumab; Dacti, dactinomycin; Dex, dexamethasone; DNR, daunorubicin; Dox, doxorubicin; IVIG, intravenous immunoglobulins; L-Amb, liposomal Amphotericin B; Mitox, mitoxantrone; 6MP, 6’-mercaptopurine; MTX, methotrexate; Pred, prednisone; TG, thioguanine; VBL, vinblastine; VCR, vincristine; VP16, etoposide.

ALL

HL

23

35

ALL

22

AML

T-ALL

21

29

Malignancy

UPN

Chemotherapy prior to or at HLH

Table III. Treatment and Outcome of HLH during chemotherapy (Ch-HLH).

K. Lehmberg et al

ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

HLH in Paediatric Malignancy (24%) and in Ch-HLH, infectious triggers are even more frequent (88%). A Japanese report describing mostly adult HLH cases suggested that a high sCD25/ferritin ratio indicates lymphoma of any type (mean ratio = 12
5) as a trigger rather than a benign condition (mean ratio = 1
3), i.e. that elevation of sCD25 is more pronounced than elevation of ferritin (Tabata & Tabata, 2012). As ferritin and sCD25 was not exactly measured but was only determined to be above a certain threshold in some of our patients, we cannot formally confirm or dismiss this finding in our cohort. The median overall survival (1
2 years) and 6 month survival rate of 67% in M-HLH are in accordance with other paediatric reports (Veerakul et al, 2002; Celkan et al, 2009). A strict distinction of the cause of death between the malignancy itself and the hyperinflammation is rarely possible. However, a substantial proportion of deceased patients with M-HLH (7 out of 11) had active HLH and malignant disease at death. This suggests HLH contributes to the mortality, particularly in T-NHL patients. In a series of 13 children and adolescents (five with leukaemia and eight patients with rhabdomyosarcoma, neuroblastoma or lymphoma, excluding one case of Langerhans cell histiocytosis), overall survival was 54% (Celkan et al, 2009). In another report, survival of 25 patients with HLH in the context of malignancy (without clear differentiation between M-HLH and Ch-HLH) was 52%, overall 36% (Veerakul et al, 2002). In Ch-HLH, the 6-month overall survival rate was 63%. In the paediatric literature, outcome of Ch-HLH is variable: In a cohort of 15 patients, overall survival was 80% (Celkan et al, 2009); in a series of six patients, three patients died from HLH (Lackner et al, 2008), while no patient out of four survived in another report (Trebo et al, 2005). From this analysis, no clear conclusion can be drawn regarding the superiority of initially administering an HLHdirected regimen (before or in combination with the malignoma protocol) or a malignancy-directed treatment. All firstline malignancy-directed treatment schemes used in the MHLH group contained agents known to be active in HLH (corticosteroids, etoposide, cyclophosphamide). In ALCL, response of HLH to malignancy-directed therapy (a protocol containing dexamethasone in the prephase and VP16 in the immediately following first cycle) was mostly promising; however the rate of patients requiring HSCT for persistence of lymphoma or relapse was high. Overall survival of T-NHL (other than ALCL) and DLBCL was poor regardless of the applied therapy. HLH in Hodgkin lymphoma responded well to a Hodgkin lymphoma protocol containing prednisone and VP16, except for an unusual case of the lymphocyte-predominant form with recurrent HLH and lymphoma. One may thus consider administering a malignancy-directed initial cycle, particularly if it contains VP16 and corticosteroids. Rituximab has shown beneficial effects in EBV-driven HLH

ª 2015 John Wiley & Sons Ltd British Journal of Haematology, 2015, 170, 539–549

(Chellapandian et al, 2013). In addition to their use for the treatment of CD20 positive malignancy, anti-CD20 antibodies should thus be considered in EBV-positive HLH in a malignant condition. The best therapeutic approach to Ch-HLH remains elusive. Under the assumption that Ch-HLH is based on iatrogenic immunosuppression and a consecutive triggering infection (proven or suspected), withdrawing or postponing malignancy-directed therapy is the logical conclusion. No doubt, a treatable infectious trigger must be targeted. However, additional therapy was considered necessary in seven out of eight patients. Whether the addition of VP16 to steroid therapy is beneficial is unclear. Haemophagocytic lymphohistiocytosis in malignant disease in paediatrics remains a challenge that has substantial mortality but is not invariably fatal. Treatment decisions must be taken case-by-case. Future efforts are warranted to enhance awareness, adapt current diagnostic criteria, elucidate the underlying biology and develop new biologicallybased targeted treatments with the aim to improve the outcome of future children and adolescents who develop this disorder.

Acknowledgements The authors would like to thank Sandra Standke for support in data management, Manuela Adao for technical assistance in gene sequencing (University Medical Centre Hamburg, Germany), Yenan Bryceson (Karolinska Institutet, Stockholm, Sweden) for the identification of the heterozygous STX11 mutation and contribution to the respective phenotypic characterization in Patient 15.

Author contribution KL designed the study, collected and analysed data, and wrote the manuscript. BS collected and analysed data. KN contributed to the design of the study and collected patient data. WW, IM, MS, TB, KB, SFNB, KK, RK, AL, MM, FHS, IS, SV collected patient data. SE performed flow cytometric analyses for the identification of hereditary defects. UzS performed genetic analyses. GEJ designed the study, collected patient data and contributed to the writing of the manuscript. All authors critically revised and approved of the final version of the manuscript. Competing interests: the authors have no competing interests.

Supporting Information Additional Supporting Information may be found in the online version of this article: Table SI. Clinical and laboratory features at HLH onset and hereditary defects.

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