Abstract | PURPOSE: Early-stage testicular seminoma is among the most radiosensitive tumors, with an overall cure rate of over 90%. Among those cured of the disease by orchiectomy and postoperative irradiation, there is a risk of having a second malignancy. We conducted a study to determine the relative risk of the occurrence of secondary malignancy. METHODS AND MATERIALS: From 1964 through 1988, 128 patients with histologically confirmed early-stage seminoma of the testis underwent orchiectomy and postoperative irradiation at the Radiation Oncology Center, Mallinckrodt Institute of Radiology, and affiliate hospitals. The follow-up periods ranged from 5 to 29 years, with a median of 11.7 years. The expected rate of developing a second cancer was computed by the standardized incidence ratio using the Connecticut Tumor Registry Database. The rate is based on the number of person-years at risk, taking into account age, gender, and race. RESULTS: Nine second nontesticular malignancies were found; the time of appearance in years is indicated in brackets: two squamous cell carcinomas of the lung [3, 11], one adenocarcinoma of the rectum [15], one chronic lymphocytic leukemia [2], one adenocarcinoma of the pancreas [14], one diffuse histiocytic lymphoma of the adrenal gland [7], one sarcoma of the pelvis [5], and two transitional cell carcinomas of the renal pelvis and ureter [14, 17]. One patient who developed a contralateral testicular tumor was excluded from risk assessment. The actuarial risk of second nontesticular cancer is 3%, 5%, and 20%, respectively, at 5, 10, and 15 years of follow-up. When compared with the general population, the overall risk of second nontesticular cancer in the study group did not reach the 0.05 significance level, with an observed/expected (O/E) ratio of 2.09 (95% confidence interval, 0.39-3.35). When analyzed by the latency period after radiation treatment, during the period of 11 to 15 years, the risk was higher (O/E ratio of 4.45, 95% confidence interval, 1.22-11.63) than expected. The median duration for developing a second cancer was 11 years for tumors arising from tissues outside the irradiated field and 14 years for those within or near the irradiated area. CONCLUSIONS: The overall observed incidence of second nontesticular malignancy among patients with early-stage testicular seminoma treated with adjuvant radiation therapy was not significantly increased in comparison with the expected incidence. Clinical implications are discussed.
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Authors | C K Chao, P P Lai, J M Michalski, C A Perez |
Journal | International journal of radiation oncology, biology, physics
(Int J Radiat Oncol Biol Phys)
Vol. 33
Issue 4
Pg. 831-5
(Nov 01 1995)
ISSN: 0360-3016 [Print] United States |
PMID | 7591890
(Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
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Topics |
- Adolescent
- Adult
- Aged
- Combined Modality Therapy
- Follow-Up Studies
- Humans
- Incidence
- Male
- Middle Aged
- Neoplasms, Radiation-Induced
(epidemiology)
- Neoplasms, Second Primary
(epidemiology, etiology)
- Orchiectomy
- Retrospective Studies
- Seminoma
(radiotherapy, surgery)
- Testicular Neoplasms
(radiotherapy, surgery)
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