Second malignant neoplasms among long-term survivors of testicular cancer. Free

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With the advent of effective therapies for testicular cancer and improved long-term survival, the clinical implications of late effects of therapy are becoming increasingly important. We quantified the risk of second cancers among 13,764 one-year survivors of testicular cancer, including 1,713 20-year survivors, reported to 9 population-based cancer registries that comprise the SEER Program (1973 –2000). Excluding contralateral testis, 620 second cancers were observed (O) compared with 481 expected (E) (O/E ratio = 1.3; 95% CI = 1.2 –1.4), resulting in an excess absolute risk of 9.6 cancers per 10,000 men per year. Significant excesses were observed for acute nonlymphocytic leukemia (ANLL) (O/E = 4.0) and cancers of the rectum (O/E = 1.7), pancreas (O/E = 2.5), urinary bladder (O/E = 1.6), kidney (O/E = 1.7), and thyroid (O/E = 2.0). Risks for all second cancers other than testis were 1.3, 1.2, 1.2, and 1.4, respectively, at 1-4 years, 5-9 years, 10-19 years, and 20 or more years after testis cancer diagnosis (P_trend = 0.42). Among patients whose initial course of treatment included radiotherapy, corresponding risks were 1.2, 1.3, 1.3, and 1.6 (P_trend = 0.36); risks among other patients were 1.3, 0.9, 1.0, and 1.3, respectively. Elevated risks of solid tumors (O/E = 1.4; 95% CI = 1.1 –1.8) among 20-year survivors included bladder cancer (O/E = 3.0, P < 0.05) and non-significant excesses of cancers of esophagus (O/E = 4.0) and pancreas (O/E = 2.7). The distribution of elevated site-specific risks and temporal patterns between treatment groups was suggestive of late effects of radiation for cancers of the bladder and possibly esophagus. Significantly increased risks of ANLL were observed among patients whose initial treatment included any chemotherapy (O/E = 10.0) and those given radiotherapy alone (O/E = 2.7). The risk of all solid tumors was significantly elevated among men with seminoma (O/E = 1.3; 95% CI = 1.2 –1.4), but not those with non-seminomatous germ cell tumors (NSGCT) (O/E = 1.1; 95% CI = 0.9 –1.3); significantly increased risks for second cancers of esophagus (O/E = 2.1) and bladder (O/E = 1.8) were restricted to seminoma patients, who were more likely to have been irradiated. Taking into account competing risks, the cumulative risk of all solid tumors other than testis 25 years after testicular cancer diagnosis was 15.5% (95% CI = 13.2 –17.8%) (about one in seven) for men with seminoma and 5.8% (95% CI = 4.2 –7.4%) for those with NSGCT, a difference which may reflect in part the generally younger age of patients with NSGCT. These data suggest that a number of influences may affect the development of second cancers following testicular cancer, although the exact contributions of treatment and other factors need to be clarified.