Pancreatic undifferentiated carcinoma with osteoclast-like giant cells curatively resected after pembrolizumab therapy for lung metastases: a case report

Abstract

Background: Therapy targeting programmed death-1 or programmed death-1 ligand-1 (PD-1/PD-L1) has been developed for various solid malignant tumors, such as melanoma and non-small-cell lung cancer (NSCLC), but this approach has little effect in the treatment of pancreatic cancer. Pancreatic undifferentiated carcinoma with osteoclast-like giant cells (UCOGC) is a rare pancreatic malignancy having unique morphology and is considered a variant of pancreatic ductal adenocarcinoma (PDAC). Although UCOGC has been reported to have better prognosis than conventional PDAC, the optimal treatment for UCOGC with distant metastases has not been determined. Case presentation: A 66-year-old man was initially diagnosed with NSCLC with multiple intrapulmonary metastases and abdominal lymph node metastasis in the tail of the pancreas, and bronchial biopsy and diagnostic imaging were performed. Pathologic examination of the lung showed poorly differentiated adenocarcinoma cells expressing epithelial marker and PD-L1. Therefore, pembrolizumab monotherapy for NSCLC was given. The pulmonary lesions shrank markedly and were in complete remission after 8 months of anti-PD-1 therapy, though no therapeutic effect was observed in the pancreatic site. Distal pancreatectomy was then performed, and histopathological examination showed that the tumor was UCOGC originating from the pancreas. The histologic findings of the resected specimen mimicked those of the lung biopsy specimen, leading to the final assessment that the lung tumors were metastatic foci that migrated from the UCOGC, and only the metastatic lesions benefited from pembrolizumab therapy. Conclusion: Immune checkpoint inhibitors have limited therapeutic effects on primary lesions of pancreatic cancer, but they may exert antitumor effects on pulmonary metastases of UCOGC.

Undifferentiated Pancreatic Carcinoma With Osteoclast-Like Giant Cells: What Do We Know So Far?

“…These insights might have potential impact for therapeutic strategies and suggest a strong need for a clinical trial of immune checkpoint immunotherapy in patients with advanced PD-L1 positive UC-OGC. Such immunotherapy may also exert antitumor effects on distant metastases of UC-OGC, as recently shown (75).…”

Durable Response to PD-1 Blockade in a Patient With Metastatic Pancreatic Undifferentiated Carcinoma With Osteoclast-Like Giant Cells

“…Finally, we read with interest a recent publication by Obayashi et al 27 about a similar patient in whom pulmonary metastases from UCOCG pancreatic cancer responded to checkpoint inhibitors. However, TMB was not assessed in this patient, and the patient received treatment meant for a presumed lung cancer.…”

Undifferentiated carcinoma with osteoclast‐like giant cells of pancreas on cytology: A case report with review of literature

“…PD‐L1 could prove be an effective predictive marker for novel immunotherapy with immune checkpoint inhibitors (Pembrolizumab) especially in patients with advanced stage UCOGC 20 . Pembrolizumab monotherapy was highly effective for metastatic lung lesions after curative resection of pancreatic UCOGC 21 …”

“…20 Pembrolizumab monotherapy was highly effective for metastatic lung lesions after curative resection of pancreatic UCOGC. 21 Currently there are no standard guidelines for the management of UC-OGC. En-bloc curative resection in early stages is the main line treatment, but most studies have shown disappointing results in unresectable cases with survival of less than 1 year.…”