Mammary-type myofibroblastoma of the psoas

Abstract

Mammary myofibroblastoma is a rare, benign, mesenchymal neoplasm that was first described in the breast in 1987. However, extra-mammary-type myofibroblastoma (MTMF) was not described until 2001 as a distinct entity. We report a case of extra-MTMF arising from the retroperitoneum, which was encountered in our clinic. We also completed a review of the literature using PubMed in patients with extra-MTMF.

Editorial Comment to Retroperitoneal myofibroblastoma in an 88‐year‐old male

“…Since there have been a few cases of extramammary myofibroblastoma in the pelvic retroperitoneal space, this case was extremely rare in terms of describing detailed surgical treatment. Although extramammary myofibroblastomas are frequently asymptomatic and detected incidentally, large retroperitoneal myofibroblastomas may be accompanied by symptoms such as dysuria and malaise during defecation 2,4,5 . In this case, the patient underwent surgical resection due to frequent urination and a “pushing up” sensation from the groin during defecation 5 .…”

“…Since the first report by McMenamin et al . in 2001, 1 approximately 150 cases of extramammary myofibroblastoma have been published 2 . Of note, a series by Howitt et al .…”

“…The anatomic distribution of these tumors is widespread, with the most common, general site of involvement being the groin/inguinal region 3 . Therefore, it has been theorized that extramammary myofibroblastomas occur along the embryonic milk‐line from the axilla to the medial groin 2 . Differential diagnosis for extramammary myofibroblastoma includes both benign and malignant tumors 2 .…”

“…Therefore, it has been theorized that extramammary myofibroblastomas occur along the embryonic milk‐line from the axilla to the medial groin 2 . Differential diagnosis for extramammary myofibroblastoma includes both benign and malignant tumors 2 . Although computed tomography and magnetic resonance imaging are considered valuable in the diagnosis of myofibroblastoma, 4 extramammary fibroblastoma is difficult to diagnose.…”

“…Although computed tomography and magnetic resonance imaging are considered valuable in the diagnosis of myofibroblastoma, 4 extramammary fibroblastoma is difficult to diagnose. Thus, the most appropriate diagnostic test for a clinically or radiologically evolving soft tissue mass is a biopsy 2 . Treatment strategy should be decided based on pathological diagnosis of biopsy specimen as well as preoperative imaging.…”