Rapid progression of lentigo maligna to deeply invasive lentigo maligna melanoma. Report of two cases

Abstract

Two patients had lesions of lentigo maligna that evolved into deeply invasive (level 4-5) lentigo maligna melanoma during a relatively short period (two years and four years, respectively). In both patients, the clinical impression of lentigo maligna had been difficult to confirm by histopathologic analysis until the invasive tumor had developed. Both patients were actively followed up during this period of evolution, with our intention of detecting any early changes suggestive of invasive melanoma. Since deep invasion developed despite close clinical supervision, a more aggressive approach to the treatment of lentigo maligna may be warranted.

Diagnosis and management of lentigo maligna: a review

“…Similar to the risk of progression, the rate of progression of lentigo maligna to lentigo maligna melanoma has not been well-studied and has been estimated to range from 10 to 50 years. However, there are isolated case reports of rapid progression to invasive and metastatic melanoma from a few months to a few years [ 11 – 13 ].…”

Atypical lentiginous junctional naevi of the elderly and melanoma

“…The in situ phase of lentigo maligna may be protracted and in some individuals lasts for decades before a dermal nodule appears. However, the development of a nodule in lentigo maligna may suddenly supervene at any time and is unpredictable 9 . Some large solar lentigines can be particularly difficult to distinguish from lentigo maligna, as both may have a mottled appearance due to focal lichenoid inflammation producing black dots and areas of regression.…”

Metastatic Lentigo Maligna Melanoma

“…Once thought to have a better prognosis than other forms of melanoma, LMM is now known to have a prognosis similar to that of superficial spreading melanoma 1 . Metastasis can occur quickly, 8 as in the case reported here.…”