ORLANDO, FL, USA (UroToday.com) - The most common site of metastases in CRPC is to the bone, and other sites that are less common include lymph nodes, liver, lung, and soft tissue. Of all men with metastatic CRPC (mCRPC), about 90% have bone disease. The theory for this study was that with new therapies for mCRPC that extends survival in men with mCRPC, plus the new bone-targeted treatments, the incidence of non-bone metastases would increase with time.
In this study, the pattern of metastatic disease in mCRPC, as reported in baseline characteristics of prospective clinical trials over two decades, was evaluated by identifying all therapeutic studies in men with mCRPC in Pubmed and American Society of Clinical Oncology (ASCO) abstracts from 1990-2011. The study included men who participated in phase II or III clinical trials in mCRPC with available baseline demographic data and no exclusion of specific site of metastatic disease (except brain). Demographic data and study-reported sites of non-bone metastatic disease were recorded (lymph node, visceral, soft tissue, liver) for each of the included phase II and phase III studies. Weighted least squares linear regression models were used to evaluate temporal trends for each type of metastasis.
A total of 290 eligible studies (270 phase II and 20 phase III) were evaluated, and they involved a total of 19 110 patients. Of these, only 127 studies reported data on non-bone metastases and prior chemotherapy which made them eligible for analysis. Between 1990-2011 and 2000-2011, the proportion of patients with non-bone metastasis increased significantly, with 1.4%/year and 2.8%/year respectively, in both chemotherapy naïve and treated groups. In addition, the rate of lymph node metastasis increased between 1990-2011 (2.2%/year) and 2000-2011 (3.3%/year). At the same time, the proportion of patients with liver metastasis remained fairly stable.
To conclude, this study demonstrated an increasing trend of non-bone metastatic disease in patients with mCRPC between 1990-2011, and this included lymph node, visceral, and soft tissue metastatic disease. This was observed in both chemotherapy-naïve and chemotherapy treated patients. These observations may be due to new therapies that result in longer survival in men with mCRPC -- plus new bone targeting therapies that increase non-bone metastases. This combination may be changing the clinical presentation of patients with mCRPC.
Presented by William K. Oh, MD; Stephanie M. Doctor; James Godbold, PhD; Matthew D. Galsky MD; and Che-Kai Tsao MD at the 2013 Genitourinary Cancers Symposium - February 14 - 16, 2013 - Rosen Shingle Creek - Orlando, Florida USA
Division of Hematology and Medical Oncology, The Tisch Cancer Institute, Mount Sinai School of Medicine, New York, NY USA
Written by Anna Forsberg, medical reporter for UroToday.com