Year: 2009
Type: letter
Abstract: in Journal of Clinical Oncology examined the difference in outcomes based on the duration of adjuvant hormonal therapy in patients with locally advanced prostate cancer.Their analysis was based on the patients enrolled in the Radiation Therapy Oncology Group (RTOG) 85-31 study, 2 which was a trial of 945 men with locally advanced prostate cancer, randomly assigned to radiation therapy (RT) and adjuvant goserelin or RT alone.We agree with Souhaimi et al 1 that the appropriate duration of adjuvant hormonal modulation treatment is an important question.A recent randomized trial demonstrated that 6 months of hormones produced inferior survival as compared with 3 years of androgen blockade. 3But would 1 year be enough?What about 2 years, as was done in RTOG 92-02, showing a survival advantage in high-risk patients? 4Or, does Ͼ 5 years of hormonal modulation provide additional benefit, as suggested by Souhami et al in their analysis?Even though an analysis of the cardiovascular mortality in the RTOG 85-31 population did not demonstrate increased mortality, 5 others have certainly demonstrated significant treatment-related complications, including impotence, diabetes, decreased bone mineral density, and cardiovascular disease. 6,7 This analysis by Souhami et al 1 suggests that hormonal therapy duration (HTD) of Ͼ 5 years improved outcomes.However, in addition to the other potential biases from this retrospective analysis mentioned by the authors, our biggest concern is that a selection bias strongly skews the results in favor of the Ͼ 5 year HTD group.This bias is due to the exclusion of patients that discontinued hormonal therapy because of death, disease progression, or initiation of another hormonal therapy.By excluding those patients, the 5 years numbers in the Ͼ 5 year HTD group were, by definition, perfect.As seen in Table 2 of the article, at 5 years, not a single patient in the Ͼ 5 year HTD group died, not a single patient had a local failure, and not a single patient had a distant failure.This is because all of the patients who progressed or died while receiving hormonal therapy were excluded from the analysis.Take, for example, a patient whose cancer is simply not responsive to hormonal modulation and will recur regardless of whether antiandrogen therapy is given.If the patient stops the hormonal therapy for any reason before the recurrence is detected, he counts as a failure in either the less than 1 year or 1 to 4 year HTD group.But the same patient who continued the hormonal therapy long-term would be excluded from the analysis and not be counted as a failure for the Ͼ 5 year HTD group as long as he was still receiving hormonal therapy when the recurrence was detected.Alternatively, imagine a patient who receives antiandrogen therapy for 4 years, but then develops a myocardial infarction.At that point, if he and his physician decide to stop hormonal therapy but he ends up dying from cardiovascular complications 3 years later, he is
Source: Journal of Clinical Oncology
Authors: Kevin Lin, Steve P. Lee, Michael L. Steinberg
Institution: University of California, Los Angeles
Language: English
Subfield: Pulmonary and Respiratory Medicine
Field: Medicine
Domain: Health Sciences
Open Access status: bronze
OpenAlex ID: W2020032984