Duodenal adenocarcinoma with neuroendocrine features in a patient with acromegaly and thyroid papillary adenocarcinoma: a unique combination of endocrine neoplasia

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.

Insulin-Like Growth Factor Pathway and the Thyroid

The insulin-like growth factor (IGF) pathway comprises two activating ligands (IGF-I and IGF-II), two cell-surface receptors (IGF-IR and IGF-IIR), six IGF binding proteins (IGFBP) and nine IGFBP related proteins. IGF-I and the IGF-IR share substantial structural and functional similarities to those of insulin and its receptor. IGF-I plays important regulatory roles in the development, growth, and function of many human tissues. Its pathway intersects with those mediating the actions of many cytokines, growth factors and hormones. Among these, IGFs impact the thyroid and the hormones that it generates. Further, thyroid hormones and thyrotropin (TSH) can influence the biological effects of growth hormone and IGF-I on target tissues. The consequences of this two-way interplay can be far-reaching on many metabolic and immunologic processes. Specifically, IGF-I supports normal function, volume and hormone synthesis of the thyroid gland. Some of these effects are mediated through enhancement of sensitivity to the actions of TSH while others may be independent of pituitary function. IGF-I also participates in pathological conditions of the thyroid, including benign enlargement and tumorigenesis, such as those occurring in acromegaly. With regard to Graves' disease (GD) and the periocular process frequently associated with it, namely thyroid-associated ophthalmopathy (TAO), IGF-IR has been found overexpressed in orbital connective tissues, T and B cells in GD and TAO. Autoantibodies of the IgG class are generated in patients with GD that bind to IGF-IR and initiate the signaling from the TSHR/IGF-IR physical and functional protein complex. Further, inhibition of IGF-IR with monoclonal antibody inhibitors can attenuate signaling from either TSHR or IGF-IR. Based on those findings, the development of teprotumumab, a β-arrestin biased agonist as a therapeutic has resulted in the first medication approved by the US FDA for the treatment of TAO. Teprotumumab is now in wide clinical use in North America.

Endoscopic mucosal resection of duodenal bulb adenocarcinoma with neuroendocrine features: An extremely rare case report

Duodenal adenocarcinoma, especially duodenal bulb with neuroendocrine features (NEF), is extremely rare. Here, we report one such case of duodenal bulb adenocarcinoma with neuroendocrine features. A 63-year-old Han Chinese woman was admitted to our department with the diagnosis of a duodenal bulb polyp and underwent an endoscopic mucosal resection. The pathological findings confirmed it as duodenal bulb adenocarcinoma with NEF. The patient remains curative after one and half a years of follow-up. Duodenal adenocarcinoma with NEF might be a low malignant neuroendocrine tumor rather than a conventional adenocarcinoma. Endoscopic treatment, including endoscopic mucosal resection, might be an ideal option for the adenocarcinomas with NEF.