Angiomyomatous hamartoma is a rare disease with a predisposition for the inguinal lymph nodes. A 51-year-old male patient visited a local hospital because of a right inguinal mass, measuring 3 x 4 cm in size, which was resected. The resected specimen showed irregularly distributed thick-walled vessels in the hilum, extending into the medulla and focally into the cortex of the node, eventually becoming more dispersed and associated with smooth muscle cells splaying into sclerotic stroma. These findings are compatible with an angiomyomatous hamartoma. Another tumor-like mass appeared shortly after the resection at the same location, but was not an angiomyomatous hamartoma, rather it was composed of edematous stromal tissue with proliferating smooth muscle cells. The stromal component included thick-walled blood vessels and lymphatics. Although it could not be determined whether these associated changes in the surrounding stroma are a cause or an effect of angiomyomatous hamartoma, they indicate the clinical difficulty in determining an appropriate area of resection and may provide clues to the pathogenesis of angiomyomatous hamartoma.