Second malignant neoplasms in digestive organs after childhood cancer: a cohort-nested case-control study.

PURPOSE: Cancers of the digestive system constitute a major risk for childhood cancer survivors treated with radiotherapy once they reach adulthood. The aim of this study was to determine therapy-related risk factors for the development of a second malignancy in the digestive organs (SMDO) after a childhood cancer. METHODS AND MATERIALS: Among 4,568 2-year survivors of a childhood solid cancer diagnosed before 17 years of age at eight French and British centers, and among 25,120 patients diagnosed as having a malignant neoplasm before the age of 20 years, whose data were extracted from the Nordic Cancer Registries, we matched 58 case patients (41 men and 17 women) of SMDO and 167 controls, in their respective cohort, for sex, age at first cancer, calendar year of occurrence of the first cancer, and duration of follow-up. The radiation dose received at the site of each second malignancy and at the corresponding site of its matched control was estimated. RESULTS: The risk of developing a SMDO was 9.7-fold higher in relation to the general populations in France and the United Kingdom. In the case-control study, a strong dose-response relationship was estimated, compared with that in survivors who had not received radiotherapy; the odds ratio was 5.2 (95% CI, 1.7-16.0) for local radiation doses between 10 and 29 Gy and 9.6 (95% CI, 2.6-35.2) for doses equal to or greater than 30 Gy. Chemotherapy was also found to increase the risk of developing SMDO. CONCLUSIONS: This study confirms that childhood cancer treatments strongly increase the risk of SMDO, which occur only after a very long latency period.

Radiation dose and relapse are predictors for development of second malignant solid tumors after cancer in childhood and adolescence: a population-based case-control study in the five Nordic countries.

The aim of the study was to assess the risk with radiation therapy and chemotherapy of the first cancer in childhood and adolescence for the development of a second malignant solid tumor (SMST). Also, the role of relapse of the primary tumor was studied. It is a nested case-control study within a Nordic cohort of patients less than 20 years of age at first diagnosis 1960-1987. SMSTs were diagnosed in 1960-1991. There were 196 cases and 567 controls. The risk was increased only for radiotherapy given more than five years before the development of the SMST. A significantly increased relative risk of 1.8 was found already at doses below 1 Gy. The risk increased rapidly up to a maximum of 18.3 for doses above 30 Gy. Chemotherapy alone did not increase the risk to develop an SMST. However, in combination with radiotherapy, chemotherapy showed a significant potentiating effect. Relapse was found to be an independent risk factor for development of an SMST, with a higher relative risk for females than for males.

Risk factors for cerebrovascular deaths in patients operated and irradiated for pituitary tumors.

Vascular mortality, especially cerebrovascular disease (CVD), are the most pronounced cause of mortality in women with hypopituitarism. In a cohort of 342 patients operated and irradiated for pituitary tumors, 31 died from CVD (CVD patients) between 1952 and 1996. The study assessed whether the radiation regimens and duration of symptoms of hypopituitarism before operation differed between the 31 CVD patients and the 62 matched patients from the same cohort who had not died from CVD (control patients). Furthermore, the infarction/hemorrhage ratio, type of clinical stroke syndrome, and time to death after stroke were investigated in the CVD patients and in matched controls from the general population who had died from CVD (population controls). No significant differences in maximum or centrally absorbed dose, maximum or central biological equivalent dose, field size, or number of fraction were recorded between CVD and control patients. A significant difference in the duration of symptoms of hypopituitarism before operation was recorded, but only in women (P = 0.01). There were no significant differences in the infarction/hemorrhage ratio (P > 0.3) of lacunar or posterior circulation syndrome compared with middle cerebral artery syndrome with cortical features (P = 0.22) or the proportion of patients who died within the first month after stroke onset (60% vs. 59%, respectively) between CVD patients and population controls. In conclusion, no significant effect on CVD deaths could be detected for any radiation parameter. A long history of unsubstituted pituitary insufficiency may be a contributing factor to the very high CVD mortality among women. There were no indications of significant differences in type of stroke, clinical stroke syndromes, or stroke fatality between the CVD patients and the population controls.