Endocrine Abstracts

Background: Neuroendocrine tumors (NETs) are relatively uncommon, accounting for 10 to 14 percent of all neuroendocrine neoplasms. Twelve percent to 22% of patiens are metastatic at presentation. The most frequent primary sites are the gastrointestinal tract (62–67%) and the lung (22–27%).

Case presentation: We report the case of a 36-year-old female patient diagnosed with metastatic disease, with liver, lung and lymph nodes metastasis with unknown primary tumor site, diagnosed on magnetic resonance imaging (MRI) at the age of 34. At her first evaluation in our clinic, she presented both clinical and paraclinical signs of carcinoid syndrome, with hot flashes, increase in stool frequency and with increased neuroendocrine markers (Chromogranin A = 100 ng/ml, Serum Serotonin = 1187 ng/ml, Neural Specific Enolase = 11.6 ng/ml). Further imaging studies showed progression of the metastatic disease, with the increase both in size and number of the liver metastasis (the largest from 9 cm in December 2017 to 14 cm in August 2019) and a lung tumor increasing in size, from 1.71 cm to 8.57 cm withing the last year. She was put on somatostatin (SS) analogues (Octreotide) with increasing doses, up to 60 mg every 28 days. We mention a twin pregnancy lost at 17 weeks in July 2019, on the course of which the patient stopped treatment with Octreotide. In December 2019 she received 7.4 GBq177-Lu-DOTATOC withing the first session of peptide receptor radionuclide therapy (PRRT), with the arousing of suspicion that the primary tumoral site might be the lung lesion, as seen of PET-CT.

Conclusion: We presented the case of a 36-year-old patient with a neuroendocrine tumor of unknown site, with rapidly progressing metastatic disease, with poor response to SS analogues, with a very poor prognosis for tumor-free survival.