Case study A: Multiply recurrent merkel cell carcinoma

This patient is a 66-year-old gentleman that presented in March of 2000 after having noticed a superficial plaque on his left lower extremity a few months prior. The area was biopsied, and he was subsequently diagnosed with Merkel cell carcinoma May of 2000 (Fig. 12.1). The patient then underwent a wide excision with split-thickness skin graft and sentinel lymph node biopsy of his left inguinal base which was negative. He then received radiation therapy to the local area only. He developed a recurrence of Merkel cell carcinoma on his left lateral calf March of 2002 outside of the originally radiated area thought to be an in-transit metastasis. After a wide excision of the area, he developed another in-transit metastasis in October 2002, also located on the lateral calf area. A second wide excision of the left lateral calf area was performed with a split-thickness skin graft and a second round of radiation therapy was given between February and March of 2003. The patient was then scheduled to receive PET scans every 3 months to monitor for recurrence or systemic disease. On December 17, 2003, a new focus noted on a PET scan of the left upper medial calf overlying the gastrocnemius fascia was found and diagnosed as Merkel cell carcinoma, also thought to be an in-transit metastasis (Fig. 12.2). The patient then underwent wide local excision and postoperative radiation therapy for the third time, and was started on adjuvant Leukine (GM-CSF) therapy following the Spitler regimen of 250 μg delivered subcutaneously in 28 day cycles of 14 days receiving the injection, then 14 days of no injections. One year later, in December of 2004, a PET scan revealed a new nodule on the left lateral leg, which was diagnosed as Merkel cell carcinoma via biopsy. On December 13, 2004, this new focus of Merkel cell carcinoma as well as the previous two sites of recurrence was excised. In January of 2005 the patient underwent isolated limb infusion of chemotherapy at Sloan-Kettering in New York. A PET scan in April 2005 showed some new areas of nonspecific hypermetabolism above the left knee, but a follow-up MRI was normal. In August of 2006, however he developed another in-transit metastasis on the anterior tibia, followed by another in-transit metastasis of the posterior calf in October of 2006. At that point, he underwent circumferential radiation to the entire left lower leg below the knee December of 2006 and has been recurrence-free since then. The last PET scan was performed on June 15, 2011 and did not show any evidence of recurrence or metastatic disease.