Vigilance to misleading information is required to avoid delayed diagnosis: Case series of acral melanomas

Abstract

Introduction: Melanoma is considered a rare cancer among Asians with a wide range of mucocutaneous manifestations. Failure to recognize a lesion as melanoma at first presentation might delay surgery aimed at complete resection. Acral melanoma has been related with the highest rate of misdiagnosis (~30%) causing further delayed diagnosis. Reliability of patient' history taking in melanoma has not yet been systematically reported.

Presented cases: Two patients visited our oncology clinic with pigmented lesions in their soles. A 66-year-old man disclosed it appeared since a year ago after accidently hitting a stone while farming. Physical examination showed a black-brown irregular 100 × 80 mm lesion covering the distal third of the right sole with ulceration in the central lesion. The second patient was a geriatric woman with a black-purple 25 × 27 mm lesion with slight protrusion and ulceration in the central, irregular border, and partial hyperkeratosis. She explained the lesion emerged two years ago after she accidently stepped on a nail. Both patients were then diagnosed with acral melanomas and were treated with wide-excision, closure with skin grafting, and inguinal dissection.

Discussion: Both patients reported history of traumas in lesions later confirmed as acral melanomas. Although history taking can provide up to 80% of the information for accurate diagnosis, in ambivalent cases, careful anamnesis, clinical examination, and biopsy are required to confirm diagnosis of acral melanoma. Early disease identification to establish definitive diagnosis of cancer is generally associated with better clinical outcomes. In suspected cases, vigilance toward misleading information in history taking is required.

Keywords: Acral; Delayed diagnosis; History taking; Melanoma; Misleading.

Fig. 1

A 66-year-old man presented in the polyclinic with a black-brown irregular 100 × 80 mm skin lesion fulfilling the distal third of the right sole with ulceration in the central lesion. Nodular-shaped, purple to black lump of 3.5 cm in diameter was also observed in the right inguinal region. (For interpretation of the references to color in this figure legend, the reader is referred to the Web version of this article.)

Fig. 2

Histopathology of the skin lesion demonstrates accumulation of round, oval, epithelioid, to pleomorphic tumor cells with of intra- and extracellular melanocytic pigments that infiltrate the epidermis and surrounding soft tissues (A,C). The histological features meet the growth pattern of acral lentiginous melanoma (ALM). In the panel B, infiltration of cancer cells is observed in the lymph nodes with prominent extra-nodal extension.

Fig. 3

Clinical features of skin lesion in the left sole of a 76-year-old woman who stated that the lesion appeared after she accidently stepped on a nail one year ago. Physical examination showed a 25 × 27 mm purplish-black lesion with slight protrusion and central ulceration. The lesion has irregular border and partial hyperkeratosis.

Fig. 4

Histopathology of the lesion shows dense proliferation of atypical melanocytes that are specifically arranged in nodular and solid patterns. The tumor cells are sharply circumscribed without Pagetoid migration and lateral extension to the epidermis (A and C). Perineural invasion is observed in the Panel B, and tumor cell infiltration is shown in the Panel D.