Conservative surgical management of subungual (matrix derived) melanoma: report of seven cases and literature review.
ABSTRACT 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.
SourceAvailable from: Yasuhiro Nakamura[Show abstract] [Hide abstract]
ABSTRACT: Subungual melanoma (SUM) is rare and represents approximately 2–3% and 20% of all cutaneous melanomas in Caucasians and Asians, respectively. Amputation has usually been performed for invasive SUM; however, not all invasive SUMs invade or attach to the distal phalanx. To investigate the possibility of non-amputative surgery for patients with invasive SUM, the distances between the deepest base of the melanoma cells and the bony surface in the surgical specimens of invasive SUM were measured. Thirty surgical specimens of invasive SUM were retrospectively reviewed. The contents of the specimens were as follows: 14 first toes, 10 thumbs, three second fingers, two third fingers, and one fifth finger. Four specimens showed bone invasion, and the tumor was attached to the bone in four specimens. The tumor-to-bone distance exceeded 0.9 mm in all the specimens with thicknesses <4 mm. In the non-ulcerated SUMs (nine specimens), only one SUM specimen showed bone attachment. There was a higher likelihood of bone attachment or invasion when tumor thickness (TT) exceeded 4 mm (Pearson chi-square test, P = 0.009; Fisher exact test, P = 0.004; student t test, 0.033). Univariate and multivariate analysis also revealed that thick TT had a statistically significant affect (odds ratio 1.807 and 1.865, 95% CI 1.11–3.01 and 1.11–3.13, P = 0.023 and 0.018). Non-amputative surgery may be possible for SUM tumors that are of intermediate-thickness. However, there has been little evidence demonstrating survival with non-amputative surgery for invasive SUM. A large, randomized, prospective clinical study is required to address this issue.The Journal of Dermatology 10/2014; 41(10). DOI:10.1111/1346-8138.12622 · 2.35 Impact Factor
The Journal of Dermatology 09/2014; 41(10). DOI:10.1111/1346-8138.12605 · 2.35 Impact Factor
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ABSTRACT: Subungual melanoma is a rare subtype of melanoma that usually originates and spreads from the nail matrix. Because of its poor prognosis and short matrix-to-bone distance, amputation has been traditionally performed. Recently, conservative surgery has been attempted for early subungual melanoma, but the evidence supporting this practice is sparse. As little is known about the progression pattern of subungual melanoma, further advances on the subject may provide better guidance on the optimal surgical approach. Histopathology slides, clinical records, and photographs of 23 cases of subungual melanoma were reviewed. For all cases, each area of the nail unit-proximal nail fold, nail matrix, nail bed, and/or hyponychium-in longitudinal sections was available for histological examination. Growth pattern, dermal invasion, and thickness were assessed in each area of the nail unit. There were five cases of melanoma in situ. Eighteen cases showed dermal invasion in at least one area of the nail unit. There were no cases showing dermal invasion in the nail matrix area only. In four cases, dermal invasion involved areas of the nail unit other than the nail matrix. In 14 cases, dermal invasion involved the nail matrix area as well as other areas of the nail unit. Except for one case, the nail matrix area showed thinner dermal invasion compared with dermal invasion in other areas of the nail unit. In conclusion, dermal invasion of subungual melanoma in the nail matrix area tends to occur later than other areas of the nail unit. Longitudinal incisional biopsy is necessary to accurately evaluate melanoma invasion. The findings of this study suggest that conservative surgical treatment for early subungual melanoma may be justified as the nail matrix area, an area of thin dermis and close proximity to the underlying bone, appears to be more resistant to invasion.Modern Pathology advance online publication, 18 April 2014; doi:10.1038/modpathol.2014.65.Modern Pathology 04/2014; DOI:10.1038/modpathol.2014.65 · 6.36 Impact Factor