Wide local excision for Merkel cell carcinoma of the lower extremity: A case report

Abstract

Primary Merkel cell carcinoma (MCC) is rare and wide local excision is the primary method of treatment. However, no consensus has been reached on the best surgical approach and research is currently limited. The choice of surgical method depends on the experience of the surgeon and the situation of the patient. In the present study, the clinical data of a single case of primary MCC that was treated with wide local excision in June 2019 were retrospectively analyzed and the associated literature was reviewed. The patient underwent complete resection of the tumor, which extended 2 cm from the outer edge of the nodule and reached the subcutaneous fat layer. The wound was closed with a tension-relieving suture. The stitches were removed 15 days following surgery and the wound had healed adequately. No recurrence occurred during 30 months of follow-up. However, further multi-center prospective randomized clinical trials are required for further investigation.

Keywords: Merkel cell carcinoma; case report; resection margins; surgery; wide local excision.

Figure 1

Intraoperative presentation. (A) Image of the 3x3 cm cutaneous tumor on the right thigh. (B) Sagittal MRI. (C) Transverse MRI. (D) A 2-cm resection margin. (E) Complete resection of the tumor. (F) Resection margin reached the subcutaneous adipose layer. (G) Tension-relieving suture.

Figure 2

Pathology and immunohistochemistry of the lesion. (A-D) H&E staining of the excised tumor at magnifications of (A) x40, (B) x100, (C) x200 and (D) x400. Immunohistochemical staining for (E) cytokeratin 20(+), (F) neural cell adhesion protein (CD56) (+), (G) chromogranin A(+) and (H) synaptophysin(+) (scale bar, 200 µm).