Endocrine Abstracts

Carcinomas are the third most frequent cause of complications in acromegalic patients. It has been suggested that diabetes potentiates the risk of cancer. To assess the frequency and type of malignant neoplasms in acromegalic patients and control group; to evaluate, in both groups, the relationship between IGF-I/GH and the development of cancer, and between glucose metabolism and cancer in two centers of Buenos Aires, Argentina. Retrospective, cross-sectional study; medical records of patients with acromegaly and control group with pituitary illnesses with normal GH/IGFI, sex- and age-matched, 1985–2017, were reviewed in order to find information about the presence of any neoplastic diseases. Sixty-two acromegalic patients, 50% women; 51 controls, 55% women; mean time of follow-up was 10.2 years. Mean age of acromegalic patients and control group was: 59±14 vs 58±15 years. Nine acromegalic patients (14.5%) developed cancer; mean age when cancer appeared was 59±14 years. In two patients both diseases were simultaneously diagnosed; in the remaining patients the mean time between the diagnosis of acromegaly and cancer diagnosis was 15.7 years. The types of cancer were: colon in three male patients (33%), prostate in 2 (22%), testicular teratocarcinoma in one, breast in one female, papillary thyroid carcinoma in one female, kidney in one male. IGF-I and GH at cancer diagnosis were elevated in three patients and normal in six. Eight patients had altered glucose metabolism, only one had normal glucose levels. In the control group, four patients developed cancer (7.8%), mean age when cancer appeared was 59±24 years, and the types of cancer were: in two men lymphoma and lung cancer; in two women rhabdomyosarcoma in mediastinum and colon cancer. None of these patients had altered glucose metabolism. The relative risk of developing cancer in acromegalic patients was 1.85, IC 95% 0.65–5.66. When we compared the disturbance of glucose metabolism in both groups with cancer, acromegalic vs control, it was 88,9% vs 0.0% (P=0.007), respectively. In acromegalic patients, among those who developed cancer and those who did not, the glucose metabolism disorders were 88.9% vs 35.8% (P=0.008), respectively.

Conclusions: In our study, the risk of developing cancer in acromegalic patients was 85% higher than in the control group. Although this trend is important, statistical significance was not reached due to the small sample size. In acromegalic patients, cancer was significantly associated with disturbance of glucose metabolism.