Rare large sigmoid hamartomatous polyp in an elderly patient with atypical Peutz-Jeghers syndrome: A case report.

Background: Peutz-Jeghers (PJ) syndrome (PJS) is a rare autosomal dominant genetic disease characterized by the association of intestinal polyposis, mucosal skin pigmentation, and cancer susceptibility. PJS patients have a significantly increased risk of malignant tumors in the gastrointestinal tract and extra-gastrointestinal tract, including various epithelial malignant tumors (colorectal cancer, gastric cancer, pancreatic cancer, breast cancer, and ovarian cancer, etc.). PJS is commonly seen in children and adolescents with multiple small intestinal polyps, often causing intussusception.

Case summary: A 62-year-old male presented with intermittent left lower abdominal pain after drinking or consuming cold beverages that was accompanied by occasional hematochezia. Abdominal contrast-enhanced computed tomography indicated an isolated sigmoid colon grape-like lesion. Subsequently, the patient underwent laparoscopic surgery, and the pathological diagnosis was PJ hamartomatous polyp. PJS was not considered at the initial visit, as the patient was older, and the facial pigmentation was not obvious. However, significant pigmentation was observed in the perineum during digital rectal examination. Interestingly, we observed that the patient exhibited nodular shadows in the adrenal glands computed tomography images that may be related to pigmentation. Therefore, we performed the determination of adrenal cortical hormones, but the results were not abnormal. Combined with skin and mucosal pigmentation and laboratory examinations, the patient was diagnosed with PJS. After laparoscopic sigmoid colon resection, the patient's symptoms improved, and no discomfort symptoms were reported in the later follow-up.

Conclusion: The age of onset and lesion location of this case are different from those of typical or isolated PJS patients.