A Case of Malignant Transformation of Solitary Recurrent Cylindroma on Scalp.

A 78-year-old male presented with an asymptomatic pinkish multi-nodular mass on his frontal scalp. The lesion had recurred twice after incomplete surgical excision. Initial punch biopsy was diagnosed with cylindroma. He revisited after one year with exophytic enlargement of the mass, and two staged Mohs micrographic surgery identified well-differentiated malignant cylindroma. Histopathology in the lower dermis and periosteal layer showed atypical cells with mitosis and hyperchromatic nucleoli with increased Ki-67 index of 10% to 30%. The postoperative wound was successfully treated with negative wound pressure therapy (NPWT) and secondary intentional healing. We report this case showing malignant transformation of solitary cylindroma, and good result for secondary intention healing using NPWT for postoperative defect.