Inadequacies of the current American Joint Committee on cancer staging system for prostate cancer.

Department of Medical Informatics, The University of Texas M. D. Anderson Cancer Center, Houston, Texas 77030, USA.
Cancer (Impact Factor: 5.2). 03/2006; 106(3):559-65. DOI:10.1002/cncr.21605
Source: PubMed

ABSTRACT Two major objectives of the American Joint Committee on Cancer (AJCC) staging system are to ensure appropriate treatments for patients and to determine prognosis. AJCC stage for distant prostate cancer includes patients with regional lymph node involvement. In the current study, the authors assessed whether patients with lymph node involvement and patients with distant metastasis, as determined using the Surveillance, Epidemiology, and End Results (SEER) staging system, had similar treatment and survival duration and, thus, were grouped together appropriately in the AJCC system.
In total, 4141 patients were selected from The University of Texas M. D. Anderson Cancer Center's Tumor Registry who initially had registered at the center between January 1, 1982, and December 31, 2001, with a diagnosis of prostate cancer; had received no treatment before presentation; and had received treatment at the center. Patients with unknown stage and patients with any other primary malignancies were excluded. Descriptive analyses of demographic and disease variables were performed. Using SEER stage groups, survival analyses and Cox proportional hazards regression analyses were performed.
Treatments differed between patients with lymph node involvement and patients with distant metastasis. The median survival was 134 months for patients with lymph node involvement and 42 months for patients with distant metastasis. When these 2 groups were combined, as in the AJCC scheme, the median survival was 86 months.
The treatment and median survival of patients with lymph node involvement differed substantially from those of patients with distant metastasis. The current AJCC scheme for prostate cancer appeared to be inappropriate when considering its purpose, and the authors concluded that it should be revised.

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