Skeletal metastases in advanced pancreatic ductal adenocarcinoma (PDAC): A retrospective analysis.

Abstract

245 Background: Skeletal metastasis (SM) in advanced PDAC is an infrequent occurrence and has been previously reported to be < 2.5%. However; pathological fractures in these patients can result in intractable pain, immobilization and a significant deterioration in quality of life. Methods: A retrospective analysis was conducted of patients (pts) with advanced PDAC receiving palliative chemotherapy. Data collection included age, gender, ECOG, sites of disease, and overall survival (OS). Statistical analysis included Kaplan Meier survival analysis. Results: The 135 pts included had a median age of 65.8 years (range: 53.7–91.3); 5 (31.2%) were women and 11 (68.7%) had an ECOG performance status of 0 or 1. A majority of patients received combination therapy that was either gemcitabine or 5-flurouracil based. Sixteen pts (11.8%) had skeletal metastasis with the primary tumor located in the pancreatic body/tail (11 pts - 68.7%).The sites of SM included thoracic vertebrae (8), lumbar vertebrae (5), pelvis (5), ribs (4), sacrum (4), scapula (3), acetabulum (2), cervical vertebrae (2), femoral head (2), sternum (1) and humerus head (1). A majority of the lesions were osteolytic (62.5%) with a median time of diagnosis of SM from initial diagnosis being 1.25 months (range 0-33). Bone pain was observed as the initial symptom in 5 pts (32%), 1 pt (6.2%) had a pathological fracture. The mOS for patients with SM was 6.5 months (range 0-38) when compared to 8 months (range 0-147) without SM.The mOS for pts treated with gemcitabine based regimen was 5.75 months (range 2.5-14), and patients who received multiple lines of therapy including gemcitabine and 5-FU based regimens was 15 months (range 5-38). Survival from onset of skeletal metastases ranged from 0-14 months (mOS: 4 months). Conclusions: More effective systemic therapies which improve mOS are likely to result in increased incidence of SM. The most common sites observed were the thoracic and lumbar vertebrae and pathological fractures in these sites can be catastrophic. Therefore careful evaluation of skeletal signs and symptoms, early detection and intervention will be important to prevent morbidity and mortality from pathological fractures.