Second primary common bile duct neuroendocrine tumor after 10 years in a patient with rectal adenocarcinoma: A case report.

Background: With the improvement of cancer treatment methods and increased life expectancy of patients, the prevalence of second primary cancers has gradually increased.

Case presentation: In the present study, the case was a 58-year-old man diagnosed with rectal adenocarcinoma and underwent chemotherapy and neoadjuvant radiotherapy 10 years ago. After 5 years, he underwent a lobectomy due to lung metastasis. At the research time, he presented with itching; in ERCP, a 16-millimeter hypoechoic lesion was detected, and an FNA biopsy was performed, indicating malignancy. The patient underwent Whipple surgery, and pathology revealed a well-differentiated neuroendocrine tumor. He was discharged in good general condition.

Conclusion: This article emphasized the necessity of early detection and diagnosis of second primary cancer, as well as acting as if it was primary cancer to treat.