Clinical Characteristics of Malignant Melanoma in Southwest China: A Single-Center Series of 82 Consecutive Cases and a Meta-Analysis of 958 Reported Cases

Abstract

Purpose: The present study determined the clinical characteristics and prognostic factors in patients with malignant melanoma based on a series of 82 cases from January 2009 to December 2014 in Southwest Hospital and a meta-analysis (including 12 articles) involving 958 patients in China.

Materials and methods: The database elements included basic demographic data and prognosticators which were extracted from medical records. Statistical analyses of survival, and multivariate analyses of factors associated with survival were performed using the Kaplan-Meier method, and the Cox proportional hazard model, respectively. Literatures were identified through systematic searches in PubMed, Embase, the Cochrane Library, China National Knowledge Infrastructure (CNKI) and Weipu database (VIP) database for the period from inception to December 2015. The meta-analysis was conducted using R 3.1.1 meta-analysis software.

Results: In this series of 82 cases, the median age of the patients was 57.50 years. Melanoma was located in the foot in 79% of patients. Sixty-one patients (74.4%) were classified as stage II-III. Thirty-two patients (39.0%) had acral malignant melanoma, and 31 patients (37.8%) had nodular malignant melanoma. The clinical characteristics of melanoma were similar to those in areas outside southwest China (from results of the meta-analysis). The median survival time was 29.50 months. The 1-year, 3-year, and 5-year survival rates were 84.1%, 39.0% and 10.9%, respectively. COX regression following multi-factor analysis showed that ulcer, tumor boundary and lymph node metastasis were associated with prognosis.

Conclusions: The clinical characteristics of melanoma in Chinese were different from those in Caucasians. Ulcer, tumor margins, and lymph node metastasis were significantly associated with prognosis. Immune therapy may prolong the median survival time of patients with acral melanoma, nodular melanoma, or stage I-III disease, although these differences were not statistically significant.

Fig 1. Trends in the number of melanoma patients hospitalized in the Dermatology Department in Southwest Hospital from January 2009 to December 2014.

Fig 2. Kaplan—Meier analyses of overall survival for all patients according to the different stratums of prognostic factors (overall comparison was performed using the Mantel-Cox log-rank test).

A. Overall survival at 1 year; B. Overall survival at 3 years; C. Overall survival at 5 years.

Fig 3. The melanoma treatments that were applied to these patients.

Fig 4. Effect of immunotherapy on median survival.

A. Overall survival according to disease stage; B. Overall survival according to histology.

Fig 5. Flow chart of study inclusion.

Fig 6. Forest plot of the proportions of males in the published data.

Fig 7. Forest plot of the proportions of different stages in the published data.

A. Stage I, B. Stage II, C. Stage III, D. Stage IV.

Fig 8. Forest plot of the proportions of histopathological diagnosis in the published data.

A. Superficial spreading melanoma, B. Malignant type freckles melanoma, C. Nodular melanoma, D. Acral lentiginous melanoma.

Fig 9. Forest plot of the proportions of melanoma located in the head and face, and trunk in the published data.

A. Head and face, B. Trunk.

Fig 10. Forest plot of the proportions of melanoma located in the limb, hand and foot in the published data.

A. Limb, B. Hand, C. Foot.