Intratumoral Fat in Neurofibroma and Coexistence of Eccrine Hidrocystoma

Prevalence and clinicopathological characteristics of lipomatous neurofibromas in neurofibromatosis 1: An investigation of 229 cutaneous neurofibromas and a systematic review of the literature

“…The relationship between Lnfs and chronic injury was also proposed, respecting that in the literature the majority were located in the head and neck region, which is subjected to repeated injury (i.e., shaving, combing, and exposure to ultraviolet radiation). In our study, most Lnfs was located on the trunk, and there was no correlation between their location and the presence of adipocytes.…”

“…Nevertheless, in this situation, entrapment of normal fat tissue in neurofibromas would be expected in the peripheral region of the neurofibromas, and in our study, adipocytes were mainly located in the midportion of the neurofibromas. For the previous 55 published cases of Lnfs, the majority of tumors measured more than 1.0 cm and the largest of them had the diameter of 10 cm, and it was from an NF1 patient.…”

“…Some authors believe that Lnfs are associated with longstanding lesions and metaplastic senescent change. For the 55 Lnfs from the literature, their duration varied widely, from 6 months to 50 years . In our study, we did not investigate the time course of the lesions, as it is difficult for the patient to know the duration of each neurofibroma when they may present hundreds of tumors.…”

“…Since then, there have been few papers published and most are case reports. Moreover, they are mainly related to sporadic neurofibromas . Therefore, there is little knowledge about either the frequency of lipomatous changes in NF1‐associated neurofibromas or their clinical and histopathological characteristics.…”