Histological lymphovascular invasion is associated with nodal involvement, recurrence, and survival in patients with cutaneous malignant melanoma.

BACKGROUND

Invasion of the lymphatic or vascular vessels by the primary tumor is considered a sign of aggressive disease that leads to metastases to the regional lymph nodes and to distant sites. Although lymphovascular invasion (LVI) is one of the major characteristics of a primary melanoma tumor, its prognostic significance remains controversial.

OBJECTIVE

The objective of this study was to determine the clinical significance of LVI in melanoma patients.

METHODS

Outcomes in 705 patients with cutaneous melanoma were investigated retrospectively.

RESULTS

The median age of the patients was 52 years (range: 16-104 years). Of the 705 patients, 624 (88.5%) did not have LVI and 81 (11.5%) patients did. Melanoma patients with LVI more frequently had nodular pathology (P = 0.001), invasion to an advanced Clark level (P = 0.000), greater Breslow thickness (P = 0.000), a high mitotic rate (P = 0.018), ulceration (P = 0.000), neurotropism (P = 0.000), lymph node involvement (P = 0.000), multiple lymph node involvement (P = 0.008), recurrent disease (P = 0.003), and metastatic disease (P = 0.008) than those without LVI. However, LVI was not significantly associated with age, gender, anatomic localization, tumor-infiltrating lymphocytes, vertical growth phase, a pre-existing melanocytic nevus, or type of distant metastasis. Lymphovascular invasion was significantly associated with both recurrence-free (P = 0.000) and overall (P = 0.000) survival. On multivariate analyses, although LVI was not independently associated with RFS (P = 0.134), it retained its significance for overall survival (P = 0.000).

CONCLUSIONS

Lymphovascular invasion has significant prognostic impact on nodal involvement, recurrence, and overall survival in cutaneous melanoma.