Acta med. scand. Vol. 199, pp. 1-5, 1976
REVIEW ARTICLE
How to Use Cytodiagnostic Spleen Puncture
Spleen puncture for cytologic diagnosis has been used since the beginning of the century and Sven Moeschlin’s monograph on the method has been available since 1947, but apparently it is still an exclusive method, used routinely in very few quarters. I t has the reputation of being a dangerous intervention and the specimen obtained is usually thought to be unduly difficult to assess. These prejudicial ideas of spleen puncture are deeply rooted but in my opinion they are nevertheless fundamentally wrong. Using fine needles and a one-hund syringe the spleen puncture may. in reality, be regarded as a very safe intervention. to be avoided only in conditions of overt hemorrhagic diathesis. We have not seen any complications in more than 1000 spleen punctures performed by this method during a 10-year period. The secret with this safety may be found in the fact that when the one-hand syringe is used, both puncture and aspiration can be made in the same fraction of a second; the risk of respiratory movement of the spleen is thus avoided and the thin needle (0.7 mm 0.d.) will leave a quite negligible lesion. The bad reputation of spleen puncture may be due to experiences with coarse needles, including some time-consuming manipulations to obtain a histologic specimen. Due to the specific structure of spieen tissue such specimens will, however, rarely be satisfactory enough to justify the use of such risky methods to secure them. The histologic pictures illustrating this presentation (Figs. 1 , 2 and 3) were obtained from splenectomy specimens! The simple cytologic srneur obtained by the safe fine needle puncture is, instead, a rich source of valuable diagnostic information, often to be expressed in simple terms if only the exaggerated respect for the spleen as an enigma among organs is overcome. The ordinary hematologist will then realize that 1-752981
the spleen aspirate looks like a blood smear, though, of course, containing also a lot of cells not met with in peripheral blood. The problems are analogous with those met with in the bone marrow smear, with the important difference, however. that the cytologic picture is usually less complicated in spleen aspirates than in bone marrow smears and that i t may be assessed rather quickly using a scheduled pattern of scrutiny. This presentation is meant to be a simple approach to such a pattern of scrutiny, not a catalogue of spleen cytology in health and disease but a guide to the clinical, maybe accidental visitor to this exotic field of observation: what to expect and what to look for in the fine needle spleen aspirate. The spleen parenchyma consists of two distinct components, the white pulp and the red pulp, separated by the marginal zone, by many authors allotted the important role of immigration port of blood lymphocytes aiming at the spleen parenchyma (Fig. I ) . It is important to realize that both the white pulp and the red pulp are not only represented, but usually even distinctly separated also in smears obtained from a fluid aspirate. I t is a good plan to start the scrutiny by looking for the representation of the white pulp: small, coherent tissue fragments containing numerous lymphocytes firmly aggregated around small precapillary vessels (Fig. 4) and usually to be found at the ends of the smears. I t may be difficult to distinguish individual cells packed together in such tissue fragments, fortunately, however, a track of free cells is usually left behind each fragment during smearing, among which it is easy to distinguish some typical elements of lymphatic tissue, e.g. the centrocytes and centroblasts of germinal centers (Fig. 5 ) and the curious, phagocytic tingible body cells. The cells of the white pulp do not themselves contribute much to the clinical routine diagnosis but they serve as important landmarks in the scruActa med. scand. 199
2
re vie^^ article
Fig. 1. Survey picture of the histology of "normal" splenic parenchyma (splenectomy specimen from a case of pancytopenia). &=red pulp, Wp=white pulp, GC=germinal center, M=marginal zone, C=cord of Billroth, S =sinusoid. (Glutar aldehydelosmium tetroxide, Epon embedding, 1 pm section, May-GriinwaldGiemsa, x 126). Fig. 2. High power of framed area in Fig. I , mainly marginal zone. S=sinus lumen, C=cordal space, Pc=pulp Acta med. scand. 199
cell, PI=plasma cell in typical site, E="tails" of sinus endothelial cells. ( ~ 5 6 7 . ) Fig. 3. Splenectomy specimen from a case of aplastic anemia with slighf hemolysis. Detail from red pulp. S=sinusoid, C=cord, Pc=pulp cell, Ec=sinus endothelium. Structures marked With X are "extra" tails af sinus endothelium cells entering the sinusoid lumen, interesting structures of hitherto unknown significance. (Histotechnical data as in Fig. I . x630.)
Review article
3
Fig. 4. Fragment of white pulp in spleen aspirate from a
8 from “subnormal” spleens. (Technical data as in Fig.
case of liver cirrhosis. Arrow at precapillary vessel. (Air-dried smear, May-Griinwald-Giemsa, x 139.) Fig. 5. Centroblasts from white pulp, the same case as in Fig. 4. (Technical data as in Fig. 4. ~ 2 7 8 . ) Figs. 6, 7,8. Sinus endothelium cells in spleen aspirates, in Fig. 8 with multiple “tails”. Specimen in Fig. 7 from a case of hemolytic anemia (arrow at “tail”),Figs. 6 and
4. Fig. 6 x348, Fig. 7 ~ 5 8 0Fig. , 8 x 186.) Figs. 9. 10, 1 1 . pulp cells (arrows) from spleen aspirates, in Fig. 9 from the same case as in Fig. 3 , in Fig. 10 from
a case of hemolytic anemia, in Fig. I 1 from a case of acute thrombocytopenia (this degree of platelet phagocytosis is an unusual finding). (Technical data as in Fig. 4. Fig. 9 ~ 5 8 0 Fig. , 10 X348, Fig. 1 I ~ 5 8 0 . )
Acra med. scond. I99
4
Review article
tiny: if they are few, one has to consider previous cytotoxic or corticosteroid treatment or perhaps a massive engorgement of the spleen with blood; if they are completely absent, one has to look carefully for the specific cells of the red pulp to exclude the possibility that the object punctured was not a spleen at all. There is one more reason to care for the white pulp fragments: at their borders or in their close vicinity one may expect to find the epithelioid cells of disseminated granulomas (e.g. in miliary tuberculosis or sarcoidosis) and the Reed-Sternberg cells of Hodgkin’s disease (Fig. 15). It should be mentioned that some degree of myeloid metaplasia is a standard finding in Hodgkin’s disease, including more or less numerous megakaryocytes, which may be similar to Reed-Sternberg cells; this is an example of the really difficult diagnosis in spleen aspirates and it should be stressed that spleen puncture can never be used to exclude a splenic localization of Hodgkin’s disease. Outside the white pulp fragments the smear may be said to represent the red pulp, normally a poor representation compared with histology (Figs. 6-10) but this fact makes pathologic findings all the more conspicuous. Normally it looks like a blood smear with a modqst addition of lymphocytes, of plasma cells, of platelet aggregates (Fig. 13) and finally of the specific parenchymal cells of red pulp: sinus endothelium cells and pulp cells (Figs. 5-1 I ) . The double- (or multiple-) tailed sinus endotheliurn cells (Figs. 6-8) are unique members of the spleen cytology but often demand some acuity of observation not to be overlooked, the long tails are often poorly visible unless marked by phagocytized matter (Fig. 7). Thepulp cells of Moeschlin, the large, phagocytic cells of the Billroth cords (Figs. 9-12) are very active members of the splenic workshop but often less conspicuous than one might expect. Loaded with red cells in hemolytic conditions, with platelets in consumption thrombocytopenias or with different foreign particles taken up from blood (bacteria!) they will catch the attention as diagnostic arguments. They are heavily loaded with hemosiderin in hemolysis and hemosiderosis and in different types of metabolic disease they may take a more or less specific appearance as Gaucher cells (Fig. 16), Niemann-Pick cells or the often Gaucher-like cells seen in long-standing thrombocytopenia (Fig. 17). The cytologic picture most often looked for i n Acra med. scand. 199
spleen aspirates and easily detected also by the beginner is rnyeloid metaplasia, in myelosclerosis and chronic myeloid leukemia making the red pulp areas look like a bone marrow smear and obscuring the white pulp fragments. Myeloid metaplasia of various degrees is a long chapter in splenology. I will mention here only the pure red cell metaplasia in some hemolytic anemias and the myeloid metaplasia in different malignant lymphomas, including Hodgkin’s disease. In early stages of myelosclerosis no diagnosis is possible without a spleen puncture. Spleen puncture also contributes essentially to the diagnosis of malignant lymphoma, especially in the still poorly known group of lymphomas which apparently start in the spleen. I would especially mention the value of spleen aspirates in the cytologic diagnosis of macroglobulinemia Waldenstrom though, admittedly, this performance demands considerable experience (Fig. 14). Sometimes even a myeloma may be first detected here, but usually the colonization of the spleen by myeloma cells is a late event in the course of the disease. This illustrates the role of the spleen as a bownet placed in the circulation, the explanation of sometimes rather surprising findings. Cancer cells are now and then seen, usually few in numbers and easily overlooked. In sclerosing cancer metastasis to the skeleton osreoblasts may be found in the spleen. In acute hepatic disease numerous hepatocytes may be present in the spleen aspirate and induce doubts as to the target chosen for puncture. I have even seen tubular epithelium cells in spleen aspirates after kidney transplantation (!). Such foreign cells may appear morphologically viable but usually show some signs of degeneration. Their presence stirs the imagination regarding the normal-sized spleen as a possible source of information in diseases where nobody today would devote any attention to the spleen. Such confusing findings in spleen aspirates induce another important conclusion: the spleen puncture is not to be compared with an ordinary biopsy. There is no such thing as a specific splenopathy, awaiting the spleen biopsy for a final, peremptory diagnosis. The spleen is a mirror in which various pathologic processes all over the body may be more or less distinctly reflected, to the help of an observer who is prepared to pick up the often unexpected piece of information offered by the spleen cells. The observer best adapted to
Fig. Z2. A group of pulp cells with typical nuclei and
typical cytoplasmic staining. (May-Grunwald-Giemsa y, I 470.) Fig. 13. Sausage-like agglomerate of platelets representing thc cast of a Billroth cord-a characteristic finding in spleen aspirates. (May-Grunwald-Giemsa 294.) Fig. 14. A rosette of lymphocytes and small plasma cells
around a histiocyte in spleen aspirate from a case of Waldenstrom’s macroglobulinemia. (May-GriinwaldGiemsa x 630.)
Fig. 15. Reed-Sternberg cell in spleen aspirate. (MayGriinwald-Giemsa x 294.)
Fig. 16. Gaucher cells in spleen aspirate. (May-GrunwaldGiemsa -.,1 470.) Fig, 17. Pseudo-Gaucher cclls, a type of macrophages
sometimes conspicuous in spleen aspirates from cases of consumption thrombocytopenia. Spleen aspirate from a case of idiopathic thrombocytopenic purpura. (MayGrunwald-Giemsa x 2 100.)
Arta tned. scand. 199
Review article this task is the clinical hematologist, the bedside and office worker, who has learnt in addition to look at the cells of blood and bone marrow with his own eyes and consider their message to the clinical problem. It is to hope that this type of a colleague will become materialized also in the future. In any case, every enlarged spleen is an unsolved problem until the aspirate has been examined. Any giant spleen m a y - o r muy nut-be the site of mas-
5
sive myeloid metaplasia, and which is not less important: any palpable spleen may be something else than a spleen. I have repeatedly seen this point missed also after scintigraphy or arteriography, but the unexpected cancer is rarely missed by the fine needle.
Nils Soderstriim, Department of Internal Medicine, University Hospital, Lund, Sweden.
Acra med. scand. 199
REVIEW ARTICLE
How to Use Cytodiagnostic Spleen Puncture
Spleen puncture for cytologic diagnosis has been used since the beginning of the century and Sven Moeschlin’s monograph on the method has been available since 1947, but apparently it is still an exclusive method, used routinely in very few quarters. I t has the reputation of being a dangerous intervention and the specimen obtained is usually thought to be unduly difficult to assess. These prejudicial ideas of spleen puncture are deeply rooted but in my opinion they are nevertheless fundamentally wrong. Using fine needles and a one-hund syringe the spleen puncture may. in reality, be regarded as a very safe intervention. to be avoided only in conditions of overt hemorrhagic diathesis. We have not seen any complications in more than 1000 spleen punctures performed by this method during a 10-year period. The secret with this safety may be found in the fact that when the one-hand syringe is used, both puncture and aspiration can be made in the same fraction of a second; the risk of respiratory movement of the spleen is thus avoided and the thin needle (0.7 mm 0.d.) will leave a quite negligible lesion. The bad reputation of spleen puncture may be due to experiences with coarse needles, including some time-consuming manipulations to obtain a histologic specimen. Due to the specific structure of spieen tissue such specimens will, however, rarely be satisfactory enough to justify the use of such risky methods to secure them. The histologic pictures illustrating this presentation (Figs. 1 , 2 and 3) were obtained from splenectomy specimens! The simple cytologic srneur obtained by the safe fine needle puncture is, instead, a rich source of valuable diagnostic information, often to be expressed in simple terms if only the exaggerated respect for the spleen as an enigma among organs is overcome. The ordinary hematologist will then realize that 1-752981
the spleen aspirate looks like a blood smear, though, of course, containing also a lot of cells not met with in peripheral blood. The problems are analogous with those met with in the bone marrow smear, with the important difference, however. that the cytologic picture is usually less complicated in spleen aspirates than in bone marrow smears and that i t may be assessed rather quickly using a scheduled pattern of scrutiny. This presentation is meant to be a simple approach to such a pattern of scrutiny, not a catalogue of spleen cytology in health and disease but a guide to the clinical, maybe accidental visitor to this exotic field of observation: what to expect and what to look for in the fine needle spleen aspirate. The spleen parenchyma consists of two distinct components, the white pulp and the red pulp, separated by the marginal zone, by many authors allotted the important role of immigration port of blood lymphocytes aiming at the spleen parenchyma (Fig. I ) . It is important to realize that both the white pulp and the red pulp are not only represented, but usually even distinctly separated also in smears obtained from a fluid aspirate. I t is a good plan to start the scrutiny by looking for the representation of the white pulp: small, coherent tissue fragments containing numerous lymphocytes firmly aggregated around small precapillary vessels (Fig. 4) and usually to be found at the ends of the smears. I t may be difficult to distinguish individual cells packed together in such tissue fragments, fortunately, however, a track of free cells is usually left behind each fragment during smearing, among which it is easy to distinguish some typical elements of lymphatic tissue, e.g. the centrocytes and centroblasts of germinal centers (Fig. 5 ) and the curious, phagocytic tingible body cells. The cells of the white pulp do not themselves contribute much to the clinical routine diagnosis but they serve as important landmarks in the scruActa med. scand. 199
2
re vie^^ article
Fig. 1. Survey picture of the histology of "normal" splenic parenchyma (splenectomy specimen from a case of pancytopenia). &=red pulp, Wp=white pulp, GC=germinal center, M=marginal zone, C=cord of Billroth, S =sinusoid. (Glutar aldehydelosmium tetroxide, Epon embedding, 1 pm section, May-GriinwaldGiemsa, x 126). Fig. 2. High power of framed area in Fig. I , mainly marginal zone. S=sinus lumen, C=cordal space, Pc=pulp Acta med. scand. 199
cell, PI=plasma cell in typical site, E="tails" of sinus endothelial cells. ( ~ 5 6 7 . ) Fig. 3. Splenectomy specimen from a case of aplastic anemia with slighf hemolysis. Detail from red pulp. S=sinusoid, C=cord, Pc=pulp cell, Ec=sinus endothelium. Structures marked With X are "extra" tails af sinus endothelium cells entering the sinusoid lumen, interesting structures of hitherto unknown significance. (Histotechnical data as in Fig. I . x630.)
Review article
3
Fig. 4. Fragment of white pulp in spleen aspirate from a
8 from “subnormal” spleens. (Technical data as in Fig.
case of liver cirrhosis. Arrow at precapillary vessel. (Air-dried smear, May-Griinwald-Giemsa, x 139.) Fig. 5. Centroblasts from white pulp, the same case as in Fig. 4. (Technical data as in Fig. 4. ~ 2 7 8 . ) Figs. 6, 7,8. Sinus endothelium cells in spleen aspirates, in Fig. 8 with multiple “tails”. Specimen in Fig. 7 from a case of hemolytic anemia (arrow at “tail”),Figs. 6 and
4. Fig. 6 x348, Fig. 7 ~ 5 8 0Fig. , 8 x 186.) Figs. 9. 10, 1 1 . pulp cells (arrows) from spleen aspirates, in Fig. 9 from the same case as in Fig. 3 , in Fig. 10 from
a case of hemolytic anemia, in Fig. I 1 from a case of acute thrombocytopenia (this degree of platelet phagocytosis is an unusual finding). (Technical data as in Fig. 4. Fig. 9 ~ 5 8 0 Fig. , 10 X348, Fig. 1 I ~ 5 8 0 . )
Acra med. scond. I99
4
Review article
tiny: if they are few, one has to consider previous cytotoxic or corticosteroid treatment or perhaps a massive engorgement of the spleen with blood; if they are completely absent, one has to look carefully for the specific cells of the red pulp to exclude the possibility that the object punctured was not a spleen at all. There is one more reason to care for the white pulp fragments: at their borders or in their close vicinity one may expect to find the epithelioid cells of disseminated granulomas (e.g. in miliary tuberculosis or sarcoidosis) and the Reed-Sternberg cells of Hodgkin’s disease (Fig. 15). It should be mentioned that some degree of myeloid metaplasia is a standard finding in Hodgkin’s disease, including more or less numerous megakaryocytes, which may be similar to Reed-Sternberg cells; this is an example of the really difficult diagnosis in spleen aspirates and it should be stressed that spleen puncture can never be used to exclude a splenic localization of Hodgkin’s disease. Outside the white pulp fragments the smear may be said to represent the red pulp, normally a poor representation compared with histology (Figs. 6-10) but this fact makes pathologic findings all the more conspicuous. Normally it looks like a blood smear with a modqst addition of lymphocytes, of plasma cells, of platelet aggregates (Fig. 13) and finally of the specific parenchymal cells of red pulp: sinus endothelium cells and pulp cells (Figs. 5-1 I ) . The double- (or multiple-) tailed sinus endotheliurn cells (Figs. 6-8) are unique members of the spleen cytology but often demand some acuity of observation not to be overlooked, the long tails are often poorly visible unless marked by phagocytized matter (Fig. 7). Thepulp cells of Moeschlin, the large, phagocytic cells of the Billroth cords (Figs. 9-12) are very active members of the splenic workshop but often less conspicuous than one might expect. Loaded with red cells in hemolytic conditions, with platelets in consumption thrombocytopenias or with different foreign particles taken up from blood (bacteria!) they will catch the attention as diagnostic arguments. They are heavily loaded with hemosiderin in hemolysis and hemosiderosis and in different types of metabolic disease they may take a more or less specific appearance as Gaucher cells (Fig. 16), Niemann-Pick cells or the often Gaucher-like cells seen in long-standing thrombocytopenia (Fig. 17). The cytologic picture most often looked for i n Acra med. scand. 199
spleen aspirates and easily detected also by the beginner is rnyeloid metaplasia, in myelosclerosis and chronic myeloid leukemia making the red pulp areas look like a bone marrow smear and obscuring the white pulp fragments. Myeloid metaplasia of various degrees is a long chapter in splenology. I will mention here only the pure red cell metaplasia in some hemolytic anemias and the myeloid metaplasia in different malignant lymphomas, including Hodgkin’s disease. In early stages of myelosclerosis no diagnosis is possible without a spleen puncture. Spleen puncture also contributes essentially to the diagnosis of malignant lymphoma, especially in the still poorly known group of lymphomas which apparently start in the spleen. I would especially mention the value of spleen aspirates in the cytologic diagnosis of macroglobulinemia Waldenstrom though, admittedly, this performance demands considerable experience (Fig. 14). Sometimes even a myeloma may be first detected here, but usually the colonization of the spleen by myeloma cells is a late event in the course of the disease. This illustrates the role of the spleen as a bownet placed in the circulation, the explanation of sometimes rather surprising findings. Cancer cells are now and then seen, usually few in numbers and easily overlooked. In sclerosing cancer metastasis to the skeleton osreoblasts may be found in the spleen. In acute hepatic disease numerous hepatocytes may be present in the spleen aspirate and induce doubts as to the target chosen for puncture. I have even seen tubular epithelium cells in spleen aspirates after kidney transplantation (!). Such foreign cells may appear morphologically viable but usually show some signs of degeneration. Their presence stirs the imagination regarding the normal-sized spleen as a possible source of information in diseases where nobody today would devote any attention to the spleen. Such confusing findings in spleen aspirates induce another important conclusion: the spleen puncture is not to be compared with an ordinary biopsy. There is no such thing as a specific splenopathy, awaiting the spleen biopsy for a final, peremptory diagnosis. The spleen is a mirror in which various pathologic processes all over the body may be more or less distinctly reflected, to the help of an observer who is prepared to pick up the often unexpected piece of information offered by the spleen cells. The observer best adapted to
Fig. Z2. A group of pulp cells with typical nuclei and
typical cytoplasmic staining. (May-Grunwald-Giemsa y, I 470.) Fig. 13. Sausage-like agglomerate of platelets representing thc cast of a Billroth cord-a characteristic finding in spleen aspirates. (May-Grunwald-Giemsa 294.) Fig. 14. A rosette of lymphocytes and small plasma cells
around a histiocyte in spleen aspirate from a case of Waldenstrom’s macroglobulinemia. (May-GriinwaldGiemsa x 630.)
Fig. 15. Reed-Sternberg cell in spleen aspirate. (MayGriinwald-Giemsa x 294.)
Fig. 16. Gaucher cells in spleen aspirate. (May-GrunwaldGiemsa -.,1 470.) Fig, 17. Pseudo-Gaucher cclls, a type of macrophages
sometimes conspicuous in spleen aspirates from cases of consumption thrombocytopenia. Spleen aspirate from a case of idiopathic thrombocytopenic purpura. (MayGrunwald-Giemsa x 2 100.)
Arta tned. scand. 199
Review article this task is the clinical hematologist, the bedside and office worker, who has learnt in addition to look at the cells of blood and bone marrow with his own eyes and consider their message to the clinical problem. It is to hope that this type of a colleague will become materialized also in the future. In any case, every enlarged spleen is an unsolved problem until the aspirate has been examined. Any giant spleen m a y - o r muy nut-be the site of mas-
5
sive myeloid metaplasia, and which is not less important: any palpable spleen may be something else than a spleen. I have repeatedly seen this point missed also after scintigraphy or arteriography, but the unexpected cancer is rarely missed by the fine needle.
Nils Soderstriim, Department of Internal Medicine, University Hospital, Lund, Sweden.
Acra med. scand. 199
