fibromatosis is a group of benign fibroblastic proliferations characterized by the growth of dense, collagen-rich fibrous tissue that forms nodules, cords, or infiltrative masses, most often within fascia, tendon sheaths, or subcutaneous tissue. It differs from a solitary fibroma in that it tends to be multifocal, infiltrative, or recurrent rather than a single well-circumscribed mass, and it differs from fibrosarcoma in that it lacks metastatic potential despite sometimes aggressive local behavior. The underlying mechanism involves clonal proliferation of myofibroblasts and excessive deposition of collagen and extracellular matrix, driven in many cases by Wnt/β-catenin pathway dysregulation. Superficial forms are typically reactive or idiopathic (e.g., palmar and plantar fibromatosis), while deep forms such as aggressive fibromatosis (desmoid tumor) behave more like a locally destructive neoplasm of uncertain biologic behavior. Clinically relevant subtypes include palmar fascial fibromatosis/Dupuytren contracture (M72.0), plantar fascial fibromatosis/Ledderhose disease (M72.2), knuckle pads (M72.1), pseudosarcomatousfibromatosis (M72.4), and desmoid tumor by anatomic site (D48.110-D48.119). It is most often confused with fibroma (a discrete benign tumor, not an infiltrative process) and with fibrosarcoma (a malignant, metastasis-capable soft tissue sarcoma).
”Abnormal condition,” “process,” or “increase” — denotes a diffuse or multifocal state rather than a single lesion
The term fibroma entered medical English in the 1860s, built from fibr/o- + -oma following the 19th-century convention of naming tumors by tissue type plus the Greek suffix -oma. Fibromatosis followed in the early 20th century (circa 1930s) once pathologists needed a distinct word for multifocal, diffuse, or recurrent fibrous proliferations that behaved differently from a solitary fibroma — the added -osis signaling a widespread process rather than one discrete growth. The root fibra (“fiber”) connects fibromatosis to the entire -fibro- root family: fibrosis (fiber + abnormal-condition suffix → excess fibrous tissue formation), fibroblast (fiber + germ/formative cell → the collagen-producing cell), and fibrosarcoma (fiber + flesh/malignant-tumor suffix → malignant fibrous tumor). The suffix -osis is highly productive in medical terminology, appearing in fibrosis, necrosis, endometriosis, and osteoporosis.
🔀 ALIASES / ALTERNATE TERMS
Fibromatous(adjective form — e.g., “fibromatous nodule,” “fibromatous cord,” “fibromatous mass”)
Aggressive fibromatosis(clinical synonym for desmoid tumor; used interchangeably in oncology and surgical pathology reports)
Desmoid tumor(preferred clinical term for deep/aggressive fibromatosis; coded by anatomic site under D48.110-D48.119)
Palmar fibromatosis(fibromatosis of the palmar fascia; synonymous with Dupuytren’s contracture; M72.0)
Dupuytren’s contracture(clinical name for palmar fascial fibromatosis when flexion contracture of the digits is present; M72.0)
Plantar fibromatosis(fibromatosis of the plantar fascia; M72.2)
Ledderhose disease(eponym for plantar fascial fibromatosis; M72.2)
Knuckle pads(fibromatosis over the dorsal proximal interphalangeal joints, often coexisting with Dupuytren’s; M72.1)
Pseudosarcomatous fibromatosis(reactive proliferative fibrous lesion that mimics sarcoma histologically but is benign; M72.4)
Infantile digital fibromatosis(rare pediatric fibrous nodule of the fingers/toes, typically resolving spontaneously)
Musculoaponeurotic fibromatosis(alternate term for deep/desmoid-type fibromatosis arising from muscle and aponeurosis)
Retroperitoneal fibromatosis(deep fibromatosis arising in the retroperitoneum; coded separately as a neoplasm of uncertain behavior, D48.3)
đź”— RELATED TERMS
Fibroma — a discrete, well-circumscribed benign fibrous tumor; unlike fibromatosis it is solitary and non-infiltrative rather than diffuse or multifocal.
Fibrosarcoma — shares the o- root; the malignant, metastasis-capable counterpart of fibrous tissue proliferation.
Fibrosis — the general process of excess collagen deposition and scarring in any tissue; fibromatosis is a discrete tumor-forming subset of this broader process.
Desmoid tumor — the deep, locally aggressive form of fibromatosis arising from musculoaponeurotic tissue; distinguished by its infiltrative growth and high local recurrence rate; include D48.110-D48.119.
Dupuytren’s contracture — the clinical syndrome produced by palmar fascial fibromatosis when cord contracture causes fixed digital flexion; M72.0.
Myofibroblast — the proliferating cell type responsible for the excess collagen and contractile activity seen in fibromatosis.
Wnt/β-catenin signaling — the molecular pathway most implicated in the pathogenesis of aggressive fibromatosis/desmoid tumor.
Familial adenomatous polyposis (Gardner syndrome) — a genetic condition strongly associated with intra-abdominal desmoid tumors, requiring genetic counseling documentation; D48.114.
plantar fasciitis — an inflammatory (not proliferative) condition of the plantar fascia frequently confused with plantar fibromatosis; distinguished by absence of a discrete fibrous nodule.
necrotizing fasciitis — an unrelated, life-threatening infectious soft tissue emergency that shares the M72 fibroblastic disorders category by classification only; M72.6.
MRI of soft tissue mass — the primary diagnostic imaging modality used to characterize fibromatosis and distinguish it from sarcoma prior to biopsy.
Fasciectomy, partial palmar with release of single digit including proximal interphalangeal joint, with or without Z-plasty, other local tissue rearrangement, or skin grafting
Fasciectomy, partial palmar with release of single digit including proximal interphalangeal joint; each additional digit (List separately in addition to primary procedure)
Unlisted procedure, musculoskeletal system, general (use when the desmoid tumor’s anatomic site has no dedicated excision code family)
⚠️ Coding Note:M72.0 and M72.2 have no laterality or site-specific sub-characters, so the affected hand or foot must be documented in the clinical note even though it does not change the code. Sequencing depends on lesion type: superficial fibromatosis (M72 category) is coded as a definitive diagnosis, while desmoid tumor uses the D48.11- site-specific family effective October 1, 2023 — never report the deleted parent code D48.1- or category heading D48.11, both of which are now non-billable. A common undercoding trap is reporting only the injection (20527) without the follow-up manipulation (26341) for collagenase-treated Dupuytren’s contracture, since both are separately billable on different dates of service. For desmoid tumorexcision, confirm intraoperative documentation of tumor depth (subcutaneous vs. subfascial) and size in centimeters, since code selection within each anatomic family hinges entirely on that measurement. Payers frequently require prior authorization and pathology confirmation for desmoid tumor resection codes (22900-22905) given overlap with soft tissue sarcoma coding, and FAP/Gardner syndrome association should be flagged for genetic counseling documentation when coding D48.114.