Clinical features of skeletal metastases originated from advanced pancreatic cancer

Background: Skeletal metastases originated from advanced pancreatic cancer (SMAPC) is rare clinical entity and has reported to be less than 2.5% in whole pancreatic cancer. The clinical features of SMAPC have not yet been clarified. Methods: From 2008 to 2017, 1695 patients were diagnosed as pancreatic cancer in our hospital. Among them, 904 patients were borderline resectable, unresectable or recurrence progressive pancreatic cancer. Thirty patients were diagnosed as pancreatic cancer with skeletal metastasis (SM). We investigated their clinical characteristics (age, sex, symptom, period from the diagnosis of pancreatic cancer to SM, metastatic site, chemotherapeutic efficacy, survival time from the date of diagnosis as SMAPC) and analyzed the relationship of clinical features with survival outcomes. Results: The 30 cases were consisted of 16 men and 14 women, with a median age of 67.5 years (range, from 44 to 75 years). Primary tumor sites were 36.7% for pancreatic head, 50% for pancreatic body and 13.3% for pancreatic tail. Thoracic vertebrae (40.0%) was the most common site of SM, and the following metastatic site were lumbar vertebrae (36.7%) and pelvic bones (26.7%). Twenty-three cases (76.7%) had pain or palsy from SM. After diagnosis of SMAPC, 16 cases (53.3%) took chemotherapy, and objective response rate was 12.5% and disease control rate was 43.8%. The median period from primary pancreatic cancer diagnosis to SM was 368 days (range, from 85 to 1782 days). The median survival time from the date of diagnosis as primary pancreatic cancer was 360 days (range, from 30 to 2494 days) and that of diagnosis as SMAPC was 125.2 days (range, from 11 to 712 days). Performance status 0, disease control and asymptomatic were favorable prognostic factors statistically. Conclusions: It is possible that clinical and radiological evaluation for early detection and intervention might be important to obtain good clinical outcomes.