Long-term survivor of a resected undifferentiated pancreatic carcinoma with osteoclast-like giant cells who underwent a second curative resection: A case report and review of the literature

Abstract
An undifferentiated carcinoma with osteoclast‑like giant cell tumors (UC‑OGC) is a rare type of tumor, which predominantly occurs in the pancreas. Due to the rarity of UC‑OGC, sufficient clinical data are not available and its prognosis following surgical resection remains unclear. In the current report the case of a 37‑year‑old female is presented, in whom an UC‑OGC of the pancreas was removed and following this, a second carcinoma of the remnant pancreas was removed during a second surgical procedure. At the patient's initial admission, the preoperative images demonstrated a well‑demarcated mass with a marked cystic component at the pancreatic head. The patient underwent a pylorus‑preserving pancreaticoduodenectomy. The final pathological diagnosis was UC‑OGC of the pancreas and the tumor was considered to have been curatively resected based on the histopathological findings. Four years after the initial surgery, a small mass was detected in the remnant pancreas and a partial resection of the remnant pancreas was subsequently performed. Histopathologically, the tumor consisted of a poorly differentiated tubular adenocarcinoma. A retrospective pathological analysis showed a segment of a poorly differentiated tubular adenocarcinoma in the initial resected specimen. Therefore, the final diagnosis was considered to be an intra‑pancreatic recurrence of UC‑OGC. The patient survived 66 months following the initial surgery and 18 months since the second resection. A meta‑analysis was performed in the current study by comparing UC‑OGC patients who survived more than two years following surgical resection (long‑term survivors) with those who succumbed less than one year following surgical resection (short‑term survivors). The characteristics of the short‑term survivors were patients of an older age, males, and those exhibiting smaller tumors, positive lymph node metastasis, and concomitant components of ductal adenocarcinoma, as well as pleomorphic giant cell carcinoma. The concomitant component of mucinous cystic neoplasm was not considered to be a prognostic factor. To the best of our knowledge, the patient in the current report is the first five‑year survivor following a curative second resection.