Objective: To investigate the clinical features and changes in the incidence of skin cancer in two hospitals located in western China.
Methods: The patients diagnosed pathologically as skin cancer from 1981 to 2000 were retrospectively collected from the two hospitals. Clinical data of patients with skin cancer were collected and analyzed.
Results: (1) Of the 1 905 patients with skin cancer, squamous cell carcinoma accounted for 29.4%(560 patients), basal cell carcinoma 28.0% (534), and cutaneous malignant melanoma(CMM) 16.0% (305). (2) There were 591 patients with skin cancer diagnosed between 1980 and 1990, and 1 314 between 1991 and 2000, and accounted for 0.34% and 0.58% of all biopsy cases, respectively. The number of total biopsy patients increased 1.6% every year during the 20 years. The number of biopsy patients with skin cancer and with CMM increased 3.5% and 3.9% every year,respectively. (3) Of the 305 CMM patients, 63.3% located on the acra. These patients were elder, and have a higher rate of trauma and a higher incidence in the male than that in patients with CMM located on the other sites. (4) Of the 305 CMM patients, 64 (21%) had history of trauma at the primary onset sites, and 47 (15.4%) had history of small congenital nevi at the primary sites.
Conclusion: There are some differences in the clinical features such as location and age between the skin cancer patients in our study and those in white population. The incidence of skin cancer in the two hospitals had been increasing in the 20 years (between 1981 and 2000). Both trauma and small congenital nevi are important risk factors of CMM.