VOLUME
32
䡠
NUMBER
4
䡠
FEBRUARY
1
2014
JOURNAL OF CLINICAL ONCOLOGY
C O R R E S P O N D E N C E
Para-Aortic Nodal Irradiation: Practical Concerns for the Radiation Oncologist TO THE EDITOR: Gouy et al1 recently reported a prospective study in locally advanced cervical cancer in which patients with negative positron emission tomography-computed tomography (PET/CT) of the para-aortic (PA) area underwent laparoscopic PA staging. The authors found a 12% false negative rate of PET/CT in the PA region. Prognostic factors of PA nodal involvement included the presence of pelvic uptake on PET/CT. The authors found that the rate of pathologically positive PA nodes was 9% in those with negative pelvic lymph nodes and 24% in those with positive pelvic nodes by PET/CT. These rates are similar to those from other published reports.2,3 The implication for the radiation oncologist is multifold. In patients who are found to have positive pelvic nodes on PET/CT and do not undergo surgical PA staging, the risk of PA nodal involvement is sufficiently high to warrant extended field radiation therapy. In addition, there appears to be a subset of those with negative pelvic nodes by PET/CT who harbor PA nodal disease and may be receiving insufficient treatment. To clarify some of the practical ramifications, we have several questions for the authors. First, In the subset of patients with negative pelvic lymph nodes and positive PA nodes, what was ithe distribution of size of the nodal metastases? In the entire cohort, the authors found that those with PA nodal metastases ⱕ 5 mm had outcomes comparable to those without PA nodal disease. If the PA disease is primarily microscopic in the subset, perhaps it is reasonable to expect chemotherapy to sterilize this disease. Otherwise, perhaps treatment intensi-
fication is required in a subset of those with radiographically nodenegative disease. Second, we are interested to learn whether the authors could identify any subset of patients with positive pelvic nodes in whom PA nodal irradiation may be excluded. We hypothesize that in patients with few involved pelvic lymph nodes or with lower location of pelvic nodal disease (as compared with common iliac nodal involvement), the risk of positive PA disease may be lower. Such data is important for optimal treatment decision making in these patients until the results of prospective randomized studies clarifying the role of PA nodal staging are available.
Malolan S. Rajagopalan and Sushil Beriwal University of Pittsburgh Cancer Institute, Pittsburgh, PA
AUTHORS’ DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
The author(s) indicated no potential conflicts of interest. REFERENCES 1. Gouy S, Morice P, Narducci F, et al: Prospective multicenter study evaluating the survival of patients with locally advanced cervical cancer undergoing laparoscopic para-aortic lymphadenectomy before chemoradiotherapy in the era of positron emission tomography imaging. J Clin Oncol 31:3026-3033, 2013 2. Ramirez PT, Jhingran A, Macapinlac HA, et al: Laparoscopic extraperitoneal para-aortic lymphadenectomy in locally advanced cervical cancer: A prospective correlation of surgical findings with positron emission tomography/computed tomography findings. Cancer 117:1928-1934, 2011 3. Margulies AL, Peres A, Barranger E, et al: Selection of patients with advanced-stage cervical cancer for para-aortic lymphadenectomy in the era of PET/CT. Anticancer Res 33:283-286, 2013
DOI: 10.1200/JCO.2013.52.9594; published online ahead of print at www.jco.org on December 23, 2013
■ ■ ■
Using Positron Emission Tomography Imaging for Maximum Benefit in Locally Advanced Cervical Cancer TO THE EDITOR: I read with interest the article by Gouy et al entitled, “Prospective Multicenter Study Evaluating the Survival of Patients With Locally Advanced Cervical Cancer Undergoing Laparoscopic Para-Aortic Lymphadenectomy Before Chemoradiotherapy in the Era of Positron Emission Tomography Imaging.”1 The authors accrued 237 patients to a prospective multicenter trial in which patients with negative positron emission tomography (PET) of the paraaortic area underwent laparoscopic para-aortic lymphadenectomy. The authors estimated that the likelihood of false-negative PET scans was 12%. Cervical cancer spreads in a predictable fashion involving first the pelvic nodes and then the para-aortic nodes. In our prior study of surgically staging locally advanced patients with cervical cancer, all patients with para-aortic nodal metastasis had PET-positive pelvic Journal of Clinical Oncology, Vol 32, No 4 (February 1), 2014: pp 357-364
nodal metastasis.2 As Gouy et al state in their discussion, “the only prognostic factor for PA nodal involvement is the presence of pelvic uptake on PET imaging.”1(p3032) If the authors could confirm that all patients with positive para-aortic nodes had positive pelvic imaging, this would provide important information for clinicians. According to Table 2, only 50 of the 237 patients in the study had uptake in the pelvis. Therefore if 29 patients with para-aortic nodal metastasis also had pelvic nodal metastasis, as I expect they did, the false negative rate of PET scans for para-aortic nodal metastasis is 0% for patients with no pelvic nodal metastasis on PET scan and 58% for patients with positive pelvic imaging on PET. Although the advent of cisplatin-based chemoradiotherapy has resulted in improvements in survival for patients with locally advanced cervical cancer, there are still improvements that can be made in individual patient treatment by using the information obtained from the PET scan, specifically, by identifying metastatic pelvic and para-aortic nodes. Our practice is to use surgical intervention (preradiotherapy lymphadenectomy) only when the PET scan demonstrates nodal metastasis with no extranodal disease. Gouy et al state that © 2013 by American Society of Clinical Oncology
Downloaded from jco.ascopubs.org on October 4, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
357
32
䡠
NUMBER
4
䡠
FEBRUARY
1
2014
JOURNAL OF CLINICAL ONCOLOGY
C O R R E S P O N D E N C E
Para-Aortic Nodal Irradiation: Practical Concerns for the Radiation Oncologist TO THE EDITOR: Gouy et al1 recently reported a prospective study in locally advanced cervical cancer in which patients with negative positron emission tomography-computed tomography (PET/CT) of the para-aortic (PA) area underwent laparoscopic PA staging. The authors found a 12% false negative rate of PET/CT in the PA region. Prognostic factors of PA nodal involvement included the presence of pelvic uptake on PET/CT. The authors found that the rate of pathologically positive PA nodes was 9% in those with negative pelvic lymph nodes and 24% in those with positive pelvic nodes by PET/CT. These rates are similar to those from other published reports.2,3 The implication for the radiation oncologist is multifold. In patients who are found to have positive pelvic nodes on PET/CT and do not undergo surgical PA staging, the risk of PA nodal involvement is sufficiently high to warrant extended field radiation therapy. In addition, there appears to be a subset of those with negative pelvic nodes by PET/CT who harbor PA nodal disease and may be receiving insufficient treatment. To clarify some of the practical ramifications, we have several questions for the authors. First, In the subset of patients with negative pelvic lymph nodes and positive PA nodes, what was ithe distribution of size of the nodal metastases? In the entire cohort, the authors found that those with PA nodal metastases ⱕ 5 mm had outcomes comparable to those without PA nodal disease. If the PA disease is primarily microscopic in the subset, perhaps it is reasonable to expect chemotherapy to sterilize this disease. Otherwise, perhaps treatment intensi-
fication is required in a subset of those with radiographically nodenegative disease. Second, we are interested to learn whether the authors could identify any subset of patients with positive pelvic nodes in whom PA nodal irradiation may be excluded. We hypothesize that in patients with few involved pelvic lymph nodes or with lower location of pelvic nodal disease (as compared with common iliac nodal involvement), the risk of positive PA disease may be lower. Such data is important for optimal treatment decision making in these patients until the results of prospective randomized studies clarifying the role of PA nodal staging are available.
Malolan S. Rajagopalan and Sushil Beriwal University of Pittsburgh Cancer Institute, Pittsburgh, PA
AUTHORS’ DISCLOSURES OF POTENTIAL CONFLICTS OF INTEREST
The author(s) indicated no potential conflicts of interest. REFERENCES 1. Gouy S, Morice P, Narducci F, et al: Prospective multicenter study evaluating the survival of patients with locally advanced cervical cancer undergoing laparoscopic para-aortic lymphadenectomy before chemoradiotherapy in the era of positron emission tomography imaging. J Clin Oncol 31:3026-3033, 2013 2. Ramirez PT, Jhingran A, Macapinlac HA, et al: Laparoscopic extraperitoneal para-aortic lymphadenectomy in locally advanced cervical cancer: A prospective correlation of surgical findings with positron emission tomography/computed tomography findings. Cancer 117:1928-1934, 2011 3. Margulies AL, Peres A, Barranger E, et al: Selection of patients with advanced-stage cervical cancer for para-aortic lymphadenectomy in the era of PET/CT. Anticancer Res 33:283-286, 2013
DOI: 10.1200/JCO.2013.52.9594; published online ahead of print at www.jco.org on December 23, 2013
■ ■ ■
Using Positron Emission Tomography Imaging for Maximum Benefit in Locally Advanced Cervical Cancer TO THE EDITOR: I read with interest the article by Gouy et al entitled, “Prospective Multicenter Study Evaluating the Survival of Patients With Locally Advanced Cervical Cancer Undergoing Laparoscopic Para-Aortic Lymphadenectomy Before Chemoradiotherapy in the Era of Positron Emission Tomography Imaging.”1 The authors accrued 237 patients to a prospective multicenter trial in which patients with negative positron emission tomography (PET) of the paraaortic area underwent laparoscopic para-aortic lymphadenectomy. The authors estimated that the likelihood of false-negative PET scans was 12%. Cervical cancer spreads in a predictable fashion involving first the pelvic nodes and then the para-aortic nodes. In our prior study of surgically staging locally advanced patients with cervical cancer, all patients with para-aortic nodal metastasis had PET-positive pelvic Journal of Clinical Oncology, Vol 32, No 4 (February 1), 2014: pp 357-364
nodal metastasis.2 As Gouy et al state in their discussion, “the only prognostic factor for PA nodal involvement is the presence of pelvic uptake on PET imaging.”1(p3032) If the authors could confirm that all patients with positive para-aortic nodes had positive pelvic imaging, this would provide important information for clinicians. According to Table 2, only 50 of the 237 patients in the study had uptake in the pelvis. Therefore if 29 patients with para-aortic nodal metastasis also had pelvic nodal metastasis, as I expect they did, the false negative rate of PET scans for para-aortic nodal metastasis is 0% for patients with no pelvic nodal metastasis on PET scan and 58% for patients with positive pelvic imaging on PET. Although the advent of cisplatin-based chemoradiotherapy has resulted in improvements in survival for patients with locally advanced cervical cancer, there are still improvements that can be made in individual patient treatment by using the information obtained from the PET scan, specifically, by identifying metastatic pelvic and para-aortic nodes. Our practice is to use surgical intervention (preradiotherapy lymphadenectomy) only when the PET scan demonstrates nodal metastasis with no extranodal disease. Gouy et al state that © 2013 by American Society of Clinical Oncology
Downloaded from jco.ascopubs.org on October 4, 2014. For personal use only. No other uses without permission. Copyright © 2014 American Society of Clinical Oncology. All rights reserved.
357
