Lasting Complete Clinical Response of a Recurring Cutaneous Squamous Cell Carcinoma With MEK Mutation and PIK3CA Amplification Achieved by Dual Trametinib and Metformin Therapy

摘要

CASE REPORT: This is the case of a 70-year-old, nonsmoker, non-drinker White man who developed a cutaneous squamous cell skin cancer in his right retroauricular region (Fig 1). Additionally, he suffered from myasthenia gravis (MG) since 2007, which, among other methods, has been treated with azathioprine (150 mg once daily) since 2011. The tumor was diagnosed in 2015 as cutaneous squamous cell carcinoma (cSCC) by biopsy. The tumor was surgically removed in December, with histology test confirming squamous cell carcinoma (SCO. In January 2016, radiotherapy with a total dose of 30 Gy in 10 fractions was administered, yet a biopsy in March showed local recurrence. Restaging of the tumor in April confirmed two fluorodeoxyglucose-avid foci on positron emission tomography-computed tomography (CT) at the operation site (Figs 2A and 2B). Re-resection of the right retroauricular recurrent cSCC was performed in April. Postoperative radiotherapy of 50 Gy in 2 Gy fractions was administered in June (Fig 2C). Three months after radiotherapy (September 2016), local recurrence prompted cisplatin plus fluorouracil chemotherapy. Responses were assessed both after the third (November 2016) and sixth (January 2017) cycles of chemotherapy by magnetic resonance imaging revealing stable disease according to RECIST 1.1, but a definitive cure could not be achieved.