fibrocartilaginous mesenchymoma of bone fibrocartilaginous mesenchymoma of bone fibrocartilaginous mesenchymoma of bone (fcmb) is an extremely rare tumor first described in 1984. about 26 cases have been reported in literature, with patient ages spanning from 9 to 25 years, though a case in a male infant aged 1 year and 7 months has been reported. quick growth and bulky size are remarkable features of this tumor. fibrocartilaginous mesenchymoma of bonespecialtyoncology diagnosis the most common locations are the shaft and epyphises of long bones (fibula and humerus) but the spine, metatarsal bones, and ilium have been involved as well. radiologic examination evidences osteolytic areas with a lobulated framework comprising radiolucent and radiodense foci admixed to speckled calcification. cortical destruction is a common finding with no soft tissue expansion in many cases. histopathology of the lesion shows large areas of mature fibrous stroma undergoing hyaline cartilage metaplasia resulting in conspicuous lobules or gradual transformation into chondroid foci. both hyaline cartilage and chondroid in turn undergo calcification and endochondral cancellous bone formation mimicking epiphyseal plate-like cartilage. differential diagnosis is concerned with fibrocartilaginous dysplasia of bone, desmoplastic fibroma, low-grade fibrosarcoma, chondromyxoid fibroma and low-grade chondrosarcoma. a full account of imaging findings on radiography, bone scan, ct and magnetic resonance has been provided by sumner et al. treatment surgery is curative despite possible local relapses. wide resection of the tumor and resection arthrodesis with an intramedullary nail, vertebrectomy and femoral head allograft replacement of the vertebral body, resection of the iliac wing and hip joint disarticulation have been among the performed procedures. the close resemblance of fcmb to fibrocartilaginous dysplasia has suggested to some scholars that they might be closely related entities, although the latter features woven bone trabeculae without osteoblastic rimming, which is a quite distinctive aspect. instead, the occurrence of epiphyseal plate-like cartilage is peculiar of the former. notes dahlin dc, bertoni f, beabout jw, campanacci m (1984). "fibrocartilaginous mesenchymoma with low-grade malignancy". skeletal radiology. 12 (4): 263–9. doi:10.1007/bf00349507. pmid 6505732. s2cid 12622136. cozzutto c, cornaglia-ferraris p (march 1991). "fibrocartilaginous mesenchymoma of bone". pathology, research and practice. 187 (2–3): 279–83. doi:10.1016/s0344-0338(11)80784-3. pmid 2068011. gambarotti m, righi a, vanel d, cocchi s, benini s, elli fm, et al. (july 2017). "fibrocartilaginous mesenchymoma of bone: a single-institution experience with molecular investigations and a review of the literature". histopathology. 71 (1): 134–142. doi:10.1111/his.13201. hdl:11577/3223054. pmid 28239886. s2cid 4787327. hayes sj, wells s, harake j, henderson jj, malcolm aj (july 2005). "fibrocartilagenous mesenchymoma of bone: the youngest reported case in a patient aged 1 year and 7 months". journal of clinical pathology. 58 (7): 782–3. pmc 1770726. pmid 15976352. gedikoglu g, aksoy mc, ruacan s (august 2001). "fibrocartilaginous mesenchymoma of the distal femur: case report and literature review". pathology international. 51 (8): 638–42. doi:10.1046/j.1440-1827.2001.01247.x. pmid 11564220. s2cid 30961094. gibson jn, reid r, mcmaster mj (september 1994). "fibrocartilaginous mesenchymoma of the fifth lumbar vertebra treated by vertebrectomy". spine. 19 (17): 1992–7. doi:10.1097/00007632-199409000-00022. pmid 7997935. s2cid 46666622. cherradi n, jelthi a, alhamany z, miri a, forest m (1999). "". clinical and experimental pathology. 47 (5): 249–55. pmid 10598375. lin j, shulman sc, steelman ck, oskouei sv, reith jd, simoneaux sf, et al. (november 2011). "fibrocartilaginous mesenchymoma, a unique osseous lesion: case report with review of the literature". skeletal radiology. 40 (11): 1495–9. doi:10.1007/s00256-011-1189-0. pmid 21560005. s2cid 2621119. martínez-lage jf, alarcón f, hernández-barceló je, almagro mj, alfaro r, galera-miñarro a (march 2010). "fibrocartilaginous mesenchymoma of the spine in a child: a case report". child's nervous system. 26 (3): 385–9. doi:10.1007/s00381-009-1042-0. pmid 20183926. s2cid 9246389. sangüesa, m. j.; laguarta, j. garcía; valverde, c. (2007). "mesenquimoma fibrocartilaginoso de hueso. caso clínico" (pdf). revista española de cirugía osteoarticular (in spanish). 42 (229): 30–33. archived from the original (pdf) on 2013-12-16. sumner te, ward wg, kilpatrick se, opatowsky mj (may 2000). "fibrocartilaginous mesenchymoma of bone: case report and review of the literature". pediatric radiology. 30 (5): 315–7. doi:10.1007/s002470050747. pmid 10836593. s2cid 29836066.