Source: Lung Cancer Online  |  Posted 8 years ago

It is critical for doctors to be aware amelanotic variants of acral melanoma may assume the morphology of benign hyperkeratotic dermatoses, report United States researchers.

Such awareness is key to curbing the current rate of missed and delayed diagnoses and to improving outcomes in patients in whom acral lentiginous melanoma is mimicking benign disease, suggests this study from Emory University School of Medicine, Atlanta, Georgia and the Bethesda Dermatopathology Laboratory, Silver Spring, Maryland.

Plantar and subungual melanoma exhibits a higher misdiagnosis rate than does melanoma at other anatomic sites. Because both incorrect and delayed diagnosis is linked with poorer outcome in these patients, the investigators retrospectively reviewed cases of plantar or lower-extremity subungual melanoma seen between 1985 and 2001 at one tertiary cancer care centre affiliated with the university.

Of the 53 cases identified, 18 were initially misdiagnosed, report Dr S L Soon and colleagues. These misdiagnoses included wart, callous, fungal disorder, foreign body, crusty lesion, sweat gland condition, blister, non-healing wound, mole, keratoacanthoma, subungual haematoma, onychomycosis, ingrown toenail and defective/infected toenail.

Nine of the 18 misdiagnosed cases were clinically amelanotic, the investigators note.

They underline understanding that these specific conditions can masquerade as benign disorders should help to increase both the rate of correct diagnosis and the outcomes for patients.