|Specimen||At our institution||At a consulted outside institution|
|#1||Atypical melanocytic neoplasm, strongly favor malignant melanoma. Note: … "Favor primary melanoma arising in a Spitz or deep penetrating nevus-like lesion. …not sure whether Clark' s and/or Breslow' s prognostic parameters would apply , but it extends to the depth of 4.0 mm, and involves deep reticular dermis (subcutis is not involved by multiple deeper levels)||Markedly atypical melanocytic tumor composed of an amelanotic epithelioid cell and pigmented deep penetrating nevus-like components; Note: I need to acknowledge some uncertainty of its biologic potential in light of some unusual features. … Consideration may also be given to sentinel lymph node biopsy as an adjunct in the evaluation of such an unusual melanocytic tumor.|
|#2||Highly atypical melanocytic neoplasm. Note: This neoplasm could be interpreted as severely atypical Spitz-like dermal neoplasm, but I cannot rule out malignancy.||Markedly atypical epithelioid melanocytic tumor of uncertain malignant potential arising in a congenital nevus. Note: I would classify this as a combined lesion with an atypical Spitz tumor of uncertain malignant potential arising in a background of a nevus. Some might designate this tumor as minimal deviation melanoma or borderline Spitz tumor.|
|#3||Compound melanocytic neoplasm with severe cytologic atypia and features of spitzoid neoplasm. Note: Neoplasm is of concern and we cannot rule out malignancy.||Malignant melanoma, in-situ and invasive arising in association with a nevus. Breslow thickness ~ 0.6 cm.|
|#4||Malignant melanoma, in-situ, with focal possible early invasion, Clark level II, Breslow thickness less than 0.1 mm arising in a compound nevus with features of dysplastic nevus.|
The neoplasms described above belong to a subset of problematic and diagnostically challenging melanocytic neoplasms variably labeled as: as atypical Spitz tumor, atypical Spitz nevus, Spitz-like lesion in the borderline category of indeterminate malignant potential, and diagnostically controversial spitzoid melanocytic tumors , as well as atypical Spitzoid neoplasms, severely atypical melanocytic neoplasms (tumors), and would also be classifiable under the category of "minimal deviation" or "nevoid" melanoma.. These lesions simultaneously exhibit some features of Spitz nevus and Spitz-like melanoma.
The cases discussed above have some features of Spitz nevus:
The same neoplasms also have some atypical features:
The biologic behavior of these atypical spitzoid melanocytic neoplasms has not been clearly elucidated. Experts often regard these lesions as having an indeterminate malignant potential. Therefore most dermatologists would recommend treating these neoplasms in a similar fashion to melanomas advising wide re-excision and SLNB depending on the measured depth of "possible" invasion (from the surface of epidermis to the bottom of the atypical melanocyte component). However, this is the problematic area, as the accepted prognostic markers (namely: Breslow's and Clark's depths and surface ulceration) do not apply well with the neoplasms that do NOT arise at the dermo-epidermal junction ).
Many ancillary diagnostic techniques have been used to try to discriminate benign lesions from malignant melanocytic.
However, currently, there is no single technique that unequivocally discriminates among these borderline lesions.
Because the status of the regional lymph nodes is a powerful predictor of overall survival for melanoma, SLNB is a useful adjunct in the management of histologically difficult melanocytic lesions. In one recent study, 8 of 18 patients (44%) with atypical spitzoid melanocytic lesions were reclassified as melanoma based on positive SLNB results . In another study 5 of 10 (50%) of diagnostically controversial spitzoid tumors metastasized to SLNs .
Our patient underwent SLNB of axillary and groin lymph nodes and there was no metastatic disease identified in any of the specimens. In addition to the wide re-excisions, he also received Interferon alpha2b therapy. The last three neoplasms described above were excised while the patient was receiving this therapy.
Contributed by Muammar Arida, MD and Drazen M. Jukic, MD, PHD.