Local recurrence of melanoma

Angiotropism in Epidermotropic Metastatic Melanoma

The diagnosis of epidermotropic metastatic malignant melanoma (EMMM) can be extremely challenging for both clinicians and pathologists. The diffculties include distinguishing metastatic lesions with an epidermal component from residual incompletely excised primary melanoma, and multiple primary melanomas. This has great prognostic significance as the current American Joint Committee on Cancer guidelines consider localized metastatic disease such as satellites and intransits in the nodal (N) category of N2C or stage IIIB disease. In this report, we present a case of EMMM with angiotropism. Additionally, we discuss in detail the differential diagnosis for recurrence of malignant melanoma with an epidermal component within the scar. Angiotropism may be seen in lesions of EMMM and the current literature suggests that angiotropism is highly suggestive of metastatic melanoma. The differential diagnosis of locally recurrent melanoma with an epidermal component can be extremely challenging and the presence of angiotropism may be a clue to the diagnosis of EMMM.

Predictors and Natural History of In-Transit Melanoma After Sentinel Lymphadenectomy

BACKGROUND

In-transit recurrence is a unique and uncommon pattern of treatment failure in patients with melanoma. Little information exists concerning the incidence, predictors, and natural history of in-transit disease since the introduction of sentinel lymph node biopsy (SLNB).

METHODS

Between 1991 and 2001, 1395 patients with primary melanoma underwent SLNB. Univariate and multivariate logistic regression analyses were performed to examine the association among known clinicopathologic factors, in-transit recurrence, and distant metastatic failure after the development of in-transit disease.

RESULTS

With a median follow-up of 3.9 years, 241 patients (17.3%) experienced disease recurrence, including 91 (6.6%) who developed in-transit recurrence. Independent predictors of in-transit recurrence included age >50 years, a lower extremity location of the primary tumor, Breslow depth, ulceration, and sentinel lymph node (SLN) status. Of the 69 patients who presented with in-transit disease as the sole site of first recurrence, 39 developed distant disease. By univariate analysis, predictors of distant failure among patients with in-transit disease included SLN status, largest metastatic focus in the SLN >2.5 mm2, subcutaneous location of in-transit disease, in-transit tumor size > or = 2 cm, and a disease-free interval before in-transit recurrence of <12 months. In-transit tumor size remained a significant predictor of distant metastasis by multivariate analysis (odds ratio, 9.69).

CONCLUSIONS

The overall incidence of in-transit metastases in patients undergoing SLNB is low and does not seem to have increased since the introduction of the SLNB technique. In-transit recurrence, as well as subsequent distant metastatic failure, can be predicted on the basis of adverse tumor factors and SLN status.

Locoregional cutaneous metastases of malignant melanoma and their management

The correct classification of locoregional metastases of malignant melanoma to skin is central to the planning of treatment. Local recurrence means persistence of neoplastic cells at the local site by virtue of incomplete excision of the primary melanoma. Standard treatment is excisional surgery. In contrast, locoregional metastases of malignant melanoma (satellites, in-transit metastases) are metastases around a primary melanoma or between a primary melanoma and regional lymph nodes. They represent intralymphatic or hematogenous spread of neoplastic cells. We present a variety of available treatment options and discuss especially topical imiquimod as a novel approach for the palliative treatment of locoregional cutaneous melanoma metastases in selected patients.

The morphological features of locally recurrent melanoma and cutaneous metastases of melanoma

Local recurrence of melanoma at the primary excision site usually implies that the primary excision was incomplete or "inadequate" and that the recurrence was attributable to retained primary melanoma cells or occult melanoma metastases in the adjacent tissue. Pathologists frequently report these tumors in the scar as recurrent or residual melanoma, apparently without considering the possibility that they may be local metastases and manifestations of systemic disease. In this study of 72 cases, we have shown that the morphological features of locally recurrent melanoma, excluding persistent incompletely excised primary melanoma, and cutaneous metastases of melanoma were identical. Because the prevention of local recurrence is the main reason for wide excision of melanoma beyond complete excision of the primary tumor itself, it is essential that pathologists should classify these neoplasms precisely as either persistent incompletely excised primary melanoma or metastatic melanoma.

The surgical treatment of primary melanoma

Local control is paramount to the clinical management of melanoma. A general consensus has been reached regarding the surgical treatment of primary malignant melanoma. By means of well-designed, multi-institutional, prospective, and randomized trials, the margins of excising the primary melanoma have been reduced considerably since the initial guidelines set out by W. S. Handley in 1907. The margins of excision now recommended are designed to limit the risk of local recurrence with its potential effect on survival and achieve the optimal cosmetic outcome. These margins are modified according to particular anatomic site constraints.