Follow, consider, and catch: second primary tumors in acromegaly patients.

Background And Aim: The risk of second primary tumors is increased in general cancer population, however, there is no data on acromegalic cancer patients in this regard. The aim of this study is to determine the prevalence of patients with two primary tumors among acromegalic cancer patients and to evaluate if patients with two primaries have distinct clinical characteristics or risk factors compared to those with one.

Methods: This is a single-center retrospective cohort study. The study included 63 patients with at least one malignant tumor out of a total number of 394 acromegaly patients. Patients with multiple primary neoplasms were evaluated in detail.

Results: This study revealed a 16% cancer prevalence in acromegaly patients, with 14% (9/63) having two primary neoplasms. Papillary thyroid carcinoma was the most prevalent tumor in the entire cancer cohort (41%, 26/63), and in the group of patients with two primaries (44%, 4/9). Patients with two primary tumors were older than those with one when diagnosed with acromegaly (48.3 ± 16.6 vs. 43.3 ± 10.7 years), which might be attributed to a longer diagnostic delay (median of 4.5 vs. 2 years). The period between the onset of acromegaly symptoms and diagnosis was not associated with earlier cancer diagnosis. No relationship between circulating GH or IGF-I levels and the number of neoplasms was found.

Conclusion: The development of second primary tumors in acromegalic patients with cancer diagnosis is not rare. Acromegalic cancer patients should be closely monitored for new symptoms or signs that could be associated with second primary tumors.