十二指腸之小細胞癌是非常罕見的並且有極差的預後。我們報告一位54歲女性因最初表現腸胃道出血與黃疸而被診斷出十二指腸的小細胞癌。腹部電腦斷層影像發現在十二指腸的第二部分有一個界線不明的腫塊，而內視鏡切片的組織學檢查顯示未分化癌。病患接受了Whipple手術及局部淋巴摘除，而病理報告表現出小細胞癌，手術檢體邊緣並未有腫瘤侵犯，但局部淋巴則被腫瘤侵犯。術後電腦斷層影像發現腫瘤復發於腫瘤床處。病患接受了補救性同步化學及放射治療，但治療引起的骨髓功能抑制造成病患無法完成全程的放射治療。雖然電腦斷層影像顯示良好的補救治療結果，腫瘤很快又長大而病患仍於最初診斷後的11個月帶病死亡。

Small cell carcinoma of the duodenum is an extremely rare disease with grave prognosis. We report a 54-year-old female who was diagnosed with small cell carcinoma in the duodenum with the initial presentation of gastrointestinal bleeding and jaundice. Abdominal computed tomography (CT) disclosed an ill-defined mass over the second part of duodenum and the histology from endoscopic biopsy demonstrated undifferentiated carcinoma. She received Whipple operation with regional lymph nodes (LNs) dissection and the pathology showed small cell carcinoma with clear surgical margins. Regional LNs were as well involved by cancer cells. Postoperative CT revealed recurrent mass at previous surgical bed. She was planned to receive salvage concurrent chemoradiation to control her disease, but treatment induced inadequate bone marrow function hindered patient to complete her full radiation course. Although CT demonstrated good salvage result, tumor enlarged again soon and the patient still died with the disease 11 months after initial diagnosis.