Subungual Melanoma

Melanoma: Hiding in Plain Sight
Presented by Mary Iaculli, MSIII and David Elpern, M.D.

A 65-year-old man presented with a three year history of a painless nail dystrophy of right fourth finger.  Assuming it to be a wart, he applied over the counter remedies without success and was told by a physician that the nail would eventually probably fall off.  The examination showed a dystrophic nail split at midline with a rough lusterless appearance. The proximal and lateral nail folds were not involved.  A wedge biopsy performed for diagnostic purposes showed an acral melanoma at least 2.5 mm thick.

Clinical photograph:

            Dermoscopic Image:

 Pathology: Acral malignant melanoma- unclassified type; Breslow thickness: at least 2.5 mm; Anatomic level: at least IV; Margins: lesion extends to the lateral and deep margins; Mitoses: 1 per mm2; Ulceration: absent; Regression: absent; Vascular invasion: absent (as confirmed by D2-40 immunostaining); AJCC pathologic stage: at least T3aNxMx.

The patient is being referred to a melanoma center for staging and definitive treatment,

Thoughts about therapy:  A radial excision of margins based on Breslow thickness. In this case, due to a thickness of at least 2.5 mm, an excision margin of 2.0 cm is recommended. Given the location, that this lesion is acral, partial amputation of the digit is most likely necessary.  Immunotherapy and biologic agents such as interferon-a-2b, ipilimumab, or vemurafenib may be helpful in treating metastatic disease, if this turns out to be the case. The recommended follow up is a physical examination every 3-4 months for 5 years with CXR and CT scan every 6 months, and annual whole-body skin examinations for life.

Teaching Points:  This was a unique presentation of subungual melanoma. Our thoughts on the initial visit were squamous cell carcinoma and chronic fungal infection. At biopsy, a black area ~ three mm in diameter was observed, raising the question of melanoma. We present this case as a reminder to always consider melanoma with a dysmorphic nail despite an amelanotic appearance and be mindful of aberrant presentations.

Questions/Discussion: Any other management recommendations? Is anyone aware of a relationship between alpha-1 antitrypsin deficiency and melanoma? Well-documented associated neoplastic processes include: lung cancer, liver cancer, gallbladder cancer, bladder cancer, and lymphoma, but not skin cancer.

1. Br J Dermatol. 2011 Oct;165(4):852-8. doi: 10.1111/j.1365-2133.2011.10477.x. Epub 2011 Aug 4.
Conservative surgical management of subungual (matrix derived) melanoma: report of seven cases and literature review.
Sureda N, Phan A, Poulalhon N, Balme B, Dalle S, Thomas L.
Department of Dermatology, Claude Bernard University, Hôpitaux de Lyon, Centre Hopitalier Lyon Sud, 69495 Pierre Bénite Cedex, France.
Subungual melanoma (SUM) is a rare entity, comprising approximately 0·7-3·5% of all melanoma subtypes. SUM histopathologically belongs to the acral lentiginous pathological subtype of malignant melanoma. Its diagnosis is helped by dermoscopy but pathological examination of doubtful cases is required. Classical management of SUM is based on radical surgery, namely distal phalanx amputation. Conservative treatment with nonamputative wide excision of the nail unit followed by a skin graft has been insufficiently reported in the medical literature even though it is performed in many centres.
To report a series of patients with in situ or minimally invasive SUM treated by conservative surgery, to investigate the postoperative evolution and to evaluate the outcome with a review of the literature.
We performed a retrospective extraction study from our melanoma register of all patients with in situ and minimally invasive SUM treated with conservative surgery in the University Hospital Department of Dermatology, Lyon, France from 2004 to 2009. The patient demographics, disease presentation, delay to diagnosis, histopathology and postoperative evolution were reviewed.
Seven cases of SUM treated as such were identified in our melanoma database. All cases had a clinical presentation of melanonychia striata. The mean delay to diagnosis was 2years. Surgical excision of the entire nail unit with a 5-10mm safety margin without bone resection followed by full-thickness skin graft taken from the arm was performed in all cases. No recurrence was observed with a mean follow-up of 45months. Functional results were found satisfactory by all patients and their referring physicians. Sixty-two other cases have been found in the literature and are also discussed.
Conservative surgical management in patients with in situ or minimally invasive SUM is a procedure with good cosmetic and functional outcome and, in our cases as well as in the literature, the prognosis is not changed.

2. Yonsei Med J. 2010 Jul;51(4):562-8. doi: 10.3349/ymj.2010.51.4.562.
Treatment and outcomes of melanoma in acral location in Korean patients.
Roh MR, Kim J, Chung KY.
Department of Dermatology and Cutaneous Biology Research Institute, Yonsei University College of Medicine, Seodaemun-gu, Seoul, Korea.
A retrospective study was conducted to review the treatment and outcomes of mainly melanomas in acral location in a single institution in Korea, and to evaluate the prognostic significance of anatomic locations of the tumor.
A retrospective review was completed on 40 patients between 2001 and 2006 to obtain pertinent demographic data, tumor data, treatment characteristics, and follow-up data.
Forty melanoma patients were identified and analyzed. Of these, 18 were male and 22 were female patients and the mean age at the time of diagnosis was 55.9 years. Of the tumors, 65% were located on the hands and feet with acral lentiginous melanoma being the most common histological subtype. Univariate analysis for the overall melanoma survival revealed that the thickness of the tumor and the clinical stage have prognostic significances. The most significant factor as analyzed by a multivariate analysis was shown to be the advanced clinical stage. Acral melanomas did not show statistically significant differences in the age at diagnosis, thickness of the tumor, stage, ulceration, and survival rates compared to non-acral melanomas. There was also no significant difference in the survival rate between the patients treated by amputation versus wide local excision in acral melanomas.
In Korean melanoma patients, thickness and advanced stages are significant factors for poorer prognosis. However, the location of melanoma did not have a significant prognostic value. In treating the melanomas in acral location, local wide excisions resulted in a similar prognosis compared to amputations.