A 55-year-old woman undergoes removal of a mature cystic teratoma. Within the dermoid, a 1.5 cm yellow nodule shows trabeculae of uniform neuroendocrine cells with acinar structures. Postoperatively she reports severe constipation for several weeks. This symptom is best explained by secretion of which substance?
- A Serotonin
- B Peptide YY ✓
- C Vasoactive intestinal peptide
- D Calcitonin
Correct answer: B. Peptide YY
Explanation
Primary ovarian carcinoid arising in a mature teratoma classically produces severe constipation because it secretes peptide YY, which inhibits gut motility. This contrasts with midgut carcinoids, which secrete serotonin and cause diarrhoea. Because the venous drainage of the ovary bypasses portal filtration into systemic circulation, carcinoid syndrome can occur without hepatic metastases.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.