Amelanotic lentigo maligna melanoma manifesting as a dermatitislike plaque

Abstract

A 72-year-old man with a previous history of an amelanotic melanoma on his left forearm had an erythematous plaque excised from his right shoulder. Although the clinical impression was a dermatitis, a biopsy specimen revealed an amelanotic lentigo maligna melanoma. To our knowledge, this is the first patient described with an amelanotic lentigo maligna melanoma as a second primary tumor to an apparent previous amelanotic melanoma, manifesting as a dermatitislike plaque.

Amelanotic Lentigo Maligna Melanoma: Mohs Surgery as the Definitive Treatment of an Invisible Tumour

“…The heterogeneous morphological presentation of ALMM, including nonpigmented edematous, erythematous scaly papules or plaques, leads the clinician to suspect a differential diagnosis including eczematous dermatitis, actinic keratosis, basal cell carcinoma, squamous cell carcinoma in situ, and squamous cell carcinoma as opposed to melanoma ( Table 1). [2][3][4][5][6][7][8][9] Due to their bland clinical presentation, amelanotic melanomas tend to be diagnosed later compared to their pigmented counterparts. 10 In a retrospective population-based study of 3467 invasive primary melanomas, of which 275 were histologically amelanotic, amelanotic melanomas were generally of a higher American Joint Committee on Cancer (AJCC) tumour stage at diagnosis compared to pigmented melanomas.…”

Dermatitis-Like Squamous Cell Carcinoma

“…A number of skin cancers can resemble dermatitis 1 . The best examples include Bowen's disease (in situ SCC), SCC, particularly of the nail bed as a periungual scaling or an erosion with crusting and nail discoloration 3 or of the ring finger after radiation exposure, 4,5 Paget's disease, extramammary Paget's disease, 6–9 amelanotic melanoma, 10 and cutaneous metastatic disease (inflammatory metastatic carcinoma) 11 (Table 1). Bowen's disease with SCCs has been described after long‐term treatment with formaldehyde‐containing antifungals, 12 although there was no evidence of topical antifungal therapy being employed on our patient.…”

Recurrent lentigo maligna as amelanotic lentigo maligna melanoma

“…Reports of amelanotic lentigo maligna (ALM) and amelanotic lentigo maligna melanoma (ALMM) are rare; there are approximately 30 cases in the literature, 2–30 but there have been only seven previous case reports describing a recurrence of a pigmented lesion or a pigmented lentigo maligna as ALM or ALMM 4,5 , 15,19 , 24,26 . We report two cases of recurrent ALMM at the site of a previously removed pigmented lentigo maligna.…”