Anatomic distribution and temporal trends of malignant melanoma among 960 cutaneous malignancies managed over 22 years at a tertiary plastic surgery department.

BACKGROUND

Melanoma, though less common than other cutaneous malignancies, remains clinically significant. In Asia, acral and nailunit melanoma-less related to ultraviolet exposure-pose diagnostic and reconstructive challenges. Clarifying temporal and anatomic trends in melanoma within plastic surgery practice may enhance early recognition and guide standardized reconstruction.

METHODS

We retrospectively reviewed 960 surgically treated cutaneous malignancies (2000-2022) in a tertiary plastic surgery department, classifying tumors as basal cell carcinoma (BCC), squamous cell carcinoma (SCC), malignant melanoma (MM), or others. For MM, we analyzed anatomic site (head/neck, trunk, non-acral extremity, acral), sex, age, comorbidities, and lifestyle factors, comparing period A (2000-2017) with period B (2018-2022). Group comparisons used the chi-square or Fisher exact test and the Mann-Whitney test. Incidence rates were calculated with Poisson confidence intervals; between-period differences were evaluated using exact binomial tests and rate ratios.

RESULTS

Of 960 tumors, BCC, SCC, MM, and others comprised 47.4%, 44.3%, 5.8%, and 2.5%. MM site distribution was heterogeneous: head/neck 14.3%, trunk 30.4%, non-acral extremity 21.4%, acral 33.9%. Distribution shifted significantly (chi-square p= 0.043), with head/neck lesions decreasing from 28.0% to 3.2% and trunk and acral lesions each increasing to 38.7%. Annual MM incidence rose from 1.39 to 6.20 cases per year (rate ratio, 4.46; p< 0.001). Hypertension (64.5%) and diabetes (35.5%) were more frequent in period B.

CONCLUSION

Recent years showed a sharply increased MM caseload and redistribution toward trunk and acral sites with greater metabolic comorbidity, reflecting both epidemiologic change and evolving detection or referral patterns.