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Rare desmoplastic fibroma of the calcaneus: A case report

Open AccessPublished:February 15, 2022DOI:https://doi.org/10.1016/j.fastrc.2022.100178

      Abstract

      Desmoplastic fibroma is a rare, benign, locally aggressive primary bone tumor. It is principally found in the mandible, pelvis, and metaphysis or meta-diaphysis of long bones and has rarely been reported in the calcaneus. The lesion is accompanied by high rates of recurrence in the literature. Treatment options include intralesional techniques via curettage ranging up to extralesional techniques via wide resection. Given the rarity of this tumor, there is a paucity of literature discussing presentation and management, especially in the lower extremity. The following case report details a 22-year-old female with an extensive desmoplastic fibroma of the calcaneus. Based on anatomic and functional considerations, this case was managed via extensive curettage with subsequent backfill with autologous and allogeneic bone graft. The post operative period was uneventful, and the patient received complete symptom relief without recurrence appreciated at 16 month follow-up.

      Keywords

      Level of Clinical Evidence

      Introduction

      Desmoplastic fibroma (DF) is a rare, benign yet locally aggressive fibrous primary bone tumor with a reported incidence in the literature ranging from 0.11%-0.13% of all primary bone tumors.
      • Stefanidis K
      • Benakis S
      • Tsatalou E
      • Ouranos V
      • Chondros D.
      Computed tomography and magnetic resonance imaging of desmoplastic fibroma with simultaneous manifestation in two unusual locations: a case report.
      ,
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      First described by Jaffe in 1958 as an uncommon benign tumor composed of small fibroblasts, it was originally likened to the soft tissue desmoid tumor of the abdominal wall due to histologic and biologic similarities.
      • Jaffe HL.
      Tumors and Tumorous Conditions of the Bones and Joints.
      Most recently, the WHO has defined DF as a rare bone tumor composed of low cellularity spindle to stellate cells in an abundant collagenous matrix with minimal cytologic atypia.
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      ,

      W.H.O. Classification. WHO Classification of Tumours Editorial Board, WHO Classification of Tumours Editorial. Soft Tissue and Bone Tumours. (2020) ISBN: 9789283245025.

      Skeletal distribution is quite widespread, with predilection for the mandible, pelvis and metaphysis or diaphysis long bones, the femur in particular.
      • Stefanidis K
      • Benakis S
      • Tsatalou E
      • Ouranos V
      • Chondros D.
      Computed tomography and magnetic resonance imaging of desmoplastic fibroma with simultaneous manifestation in two unusual locations: a case report.
      ,
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      • Nishida J
      • Tajima K
      • Abe M
      • Honda M
      • Inomata Y
      • Shimamura T
      • Shiraishi H
      • Satoh T
      • Ehara S.
      Desmoplastic fibroma. Aggressive curettage as a surgical alternative for treatment.
      • Rastogi S
      • Varshney MK
      • Trikha V
      • Khan SA
      • Mittal R.
      Desmoplastic fibroma: a report of three cases at unusual locations.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      • Böhm P
      • Kröber S
      • Greschniok A
      • Laniado M
      • Kaiserling E.
      Desmoplastic fibroma of the bone. A report of two patients, review of the literature, and therapeutic implications.
      That being said, there are published reports documenting involvement in nearly all bones of the axial and appendicular skeletons.
      • Stefanidis K
      • Benakis S
      • Tsatalou E
      • Ouranos V
      • Chondros D.
      Computed tomography and magnetic resonance imaging of desmoplastic fibroma with simultaneous manifestation in two unusual locations: a case report.
      ,
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      ,
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      • Nishida J
      • Tajima K
      • Abe M
      • Honda M
      • Inomata Y
      • Shimamura T
      • Shiraishi H
      • Satoh T
      • Ehara S.
      Desmoplastic fibroma. Aggressive curettage as a surgical alternative for treatment.
      • Rastogi S
      • Varshney MK
      • Trikha V
      • Khan SA
      • Mittal R.
      Desmoplastic fibroma: a report of three cases at unusual locations.
      ,
      • Böhm P
      • Kröber S
      • Greschniok A
      • Laniado M
      • Kaiserling E.
      Desmoplastic fibroma of the bone. A report of two patients, review of the literature, and therapeutic implications.
      The large majority of this literature consists principally of case studies and series. Documentation regarding DF presentation in the distal lower extremity is particularly sparse. More specifically, to our knowledge, there have been less than 10 reported cases of DF in the calcaneus (Table 1). Owing to the extreme rarity of DF, specifically in the calcaneus, there is a paucity of literature detailing the clinical presentation, imaging findings, and treatment options for proper identification and management of a desmoplastic fibroma. As such, the purpose of the following report is to detail a rare case of desmoplastic fibroma of the calcaneus managed with operative intervention represented as a curopsy, or biopsy with intention to cure, intralesional technique.
      • Reddy KI
      • Sinnaeve F
      • Gaston CL
      • Grimer RJ
      • Carter SR.
      Aneurysmal bone cysts: do simple treatments work?.
      The patient has given informed consent for the publication of the following case.
      Table 1Publications to date detailing reports of calcaneal desmoplastic fibroma
      YearJournalAuthorsAge/SexTreatmentRecurrenceTreatment after recurrenceFollow up
      1964Journal of the American Medical AssociationDahlin et al21/FExcision + cauterizationYesCurettage + Cauterization5 years
      1984The Journal of Bone and Joint SurgeryBertoni et al36/MIntralesional excisionNo3 years
      1985The Journal of Bone and Joint SurgeryGebhardt et al14/MCurettage + AutograftNo16 years
      1995Skeletal RadiologyYu et al21/FCurettage + AutograftUnknownUnknown
      1999Scandinavian Journal of Plastic Reconstructive and Hand SurgeryRaatikainen et al24/FCurettage + AutograftYesCurettage + Microvascular bone graft5 years
      2008Joint Bone SpineRastogi et al13/FSyme's amputationNo9 years
      2014Journal of Bone OncologyEvans et al12/FCurettageYesBKA2 years

      Case report

      A 22-year-old female initially presented to our outpatient clinic for evaluation of chronic right heel pain in September 2020. Pain had been present for approximately 5 years, and symptoms developed following the initial traumatic incident of striking the right foot against the support of a trampoline. Two months following the initial trauma, the patient sought care of an orthopedic specialist and was immobilized in an ankle brace. The patient subsequently visited a community podiatrist 2 years after the incident with continued pain but was unable to follow up due to work commitments. On an initial clinical encounter in our office, the patient endorsed intermittent pain described as a local soreness and sharp sensation. Pain was present at the lateral aspect of the hind foot, worse during ambulation. Initial physical examination produced tenderness with compression of the body of the calcaneus. There was also some low-grade edema localized to the lateral aspect of the hindfoot and notable palpable osseous prominence at the lateral aspect of the calcaneus. Neurovascular status was intact and the patient was otherwise in an excellent general state of health, without any concerns for systemic signs of occult malignancy including night sweats, recent weight loss or fatigue. Radiographs of the affected foot and ankle demonstrated an extensive mixed radiolucent and sclerotic lesion involving the entire body of the calcaneus with some cortical erosion laterally. No evidence of pathologic fracture was appreciated. As part of further work up, an MRI was obtained to evaluate the lesion and assess for potential soft tissue extension.
      MRI confirmed the entire calcaneus was replaced with a T1 hypointense, T2 mixed hyperintense and hypointense expansile lesion with heterogeneous enhancement (Fig. 1). The anterior process of the calcaneus was spared. Cortical thinning was appreciated along the lateral calcaneus, however no extension into the adjacent soft tissue was appreciated. Based on the clinical and radiographic evaluation, differential diagnoses suggested at this point included giant cell tumor, chondromyxoid fibroma, desmoplastic fibroma, non ossifying fibroma, fibrous dysplasia, chondroblastoma, and other potentially aggressive lesions. Initial suggestion included proceeding with preliminary biopsy, however, the patient preferred to proceed directly with more definitive operative intervention.
      Fig 1
      Fig. 1A-D: Preoperative MRI images. 1A: Sagittal T1 weighted image demonstrating a large hypointensity spanning the entire calcaneus except for the anterior process. 1B: Coronal T1 weighted image confirming large hypointense region within the calcaneus and expanding into the lateral soft tissues. 1C: Sagittal T2 weighted image demonstrating a mixed hypointense and hyperintense expansile lesion within the calcaneus. 1D: Coronal T2 weighted image confirming mixed hypointense and hyperintense lesion findings seen in the T2 sagittal and T1 sagittal and coronal views.
      Subsequently, the indication for operative management was established. Surgical intervention consisted of a curopsy type procedure, as described by Reddy et al, with evacuation of the material from the os calcis for biopsy and subsequent backfill with a combination autologous and allogeneic bone graft with the understanding this would serve as biopsy of the tumor as well as decreasing the tumoral burden, but not provide complete tumor resection.
      • Reddy KI
      • Sinnaeve F
      • Gaston CL
      • Grimer RJ
      • Carter SR.
      Aneurysmal bone cysts: do simple treatments work?.
      Given the extent of involvement of the calcaneus, definitive treatment options in the present case would be major proximal amputation such as below knee amputation versus total calcanectomy with possible titanium implant, which would certainly be associated with significant morbidity. Given anatomic, functional, and biomechanical considerations, en bloc resection was not a viable option. Contents were evacuated using a unique orthopedics bone harvester system. The unique harvester utilized in this case is a suction powered curettage system with the ability to harvest both cancellous bone graft as well as bone marrow aspirate in the same device. The curette attached to the distal end of the system also allows for further debridement and physical capture of any infected, diseased or non viable bone. Pertinent intraoperative findings include altered density of the fascia and periosteum overlying calcaneus. The lateral wall of the calcaneus was noted to consist of a firm fibrous cortical cancellous bone (Fig. 2). During evacuation of the contents of the calcaneus and lesion, the area was noted to be extremely avascular and composed of a combination fibrous and myxoid tissue with some cancellous bone. Fully evacuating contents of the calcaneus and this lesion did involve the entire extent of the bone. Autologous bone graft was then obtained from the distal tibial metaphysis and was exponentially aided with an allograft demineralized bone matrix in order to fill the void created within the calcaneus. Final histopathologic examination of surgical specimens revealed a spindle cell neoplasm with abundant collagen. Neoplastic cells were focally arranged in a fascicular pattern with fragments of woven bone identified embedded within the tumor, determined by our pathology team to be most consistent with a desmoplastic fibroma (Fig. 3). Postoperative course involved a period of restricted weight bearing however otherwise the patient progressed uneventfully. At 16 months, the patient reported doing well with no recurrence of symptoms.
      Fig 2
      Fig. 2A-F: Intraoperative images demonstrating curettage of bone tumor with procurement and application of autologous bone graft. 2A: Tumor confirmed as a mixed radiolucent and sclerotic lesion within the calcaneal body. 2B: Intraoperative fluoroscopy demonstrating unique bone harvester device utilized to scrape out all non viable material. 2C-D: Fibrous and myxoid tissue with cancellous bone obtained from the calcaneal body. Evacuated contents appeared largely avascular. 2E: Intraoperative fluoroscopy confirms location within the distal tibia where autologous bone graft was harvested. 2F: Application of autologous bone graft into the calcaneus.
      Fig 3
      Fig. 3A-C: Histopathology. 3A: Focal cellular area with stellate and spindle shaped fibroblasts surrounded by fine, and in areas ropey (black arrow), collagen. There is focal hemorrhage (blue arrow) and woven bone (red arrow) in this field (x100). 3B: Fascicles of spindled fibroblasts with wavy nuclei and abundant fine collagen fibrils (x400). 3C: Admixed slightly curvilinear woven bone, raising the differential diagnosis of fibrous dysplasia (x100).

      Discussion

      Desmoplastic fibroma is a rare, locally aggressive benign primary bone tumor usually affecting those in the first three decades of life, with no noted sexual predilection.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      A literature review performed by Crim et al, revealed cases of DF ranging from ages 15 months to 75 years, with a mean age of 21 years.
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      This is consistent with the age of our patient in the present case. While typically found in the mandible, pelvis, metaphysis or meta-diaphysis of long bones,
      • Nishida J
      • Tajima K
      • Abe M
      • Honda M
      • Inomata Y
      • Shimamura T
      • Shiraishi H
      • Satoh T
      • Ehara S.
      Desmoplastic fibroma. Aggressive curettage as a surgical alternative for treatment.
      ,
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      DF has been reported in the calcaneus.
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      ,
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      ,
      • Rastogi S
      • Varshney MK
      • Trikha V
      • Khan SA
      • Mittal R.
      Desmoplastic fibroma: a report of three cases at unusual locations.
      ,
      • Dahlin DC
      • Hoover NW.
      Desmoplastic Fibroma of Bone.
      • Gebhardt MC
      • Campbell CJ
      • Schiller AL
      • Mankin HJ.
      Desmoplastic fibroma of bone. A report of eight cases and review of the literature.
      • Bertoni F
      • Calderoni P
      • Bacchini P
      • Campanacci M.
      Desmoplastic fibroma of bone. A report of six cases.
      • Yu JS
      • Lawrence S
      • Pathria M
      • Resnick D
      • Haghighi P.
      Desmoplastic fibroma of the calcaneus.
      • Raatikainen TK
      • Kaarela OI
      • Holmström T
      • Kyllönen AP
      • Teerikangas HE
      • Waris TH.
      Desmoplastic fibroma of the calcaneus treated with a microvascular bone graft. Case report.
      There are no pathognomonic clinical or radiographic signs associated with this condition and occurrence is usually a slow, gradual onset, resulting in a generally nonspecific presentation.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      Typically, presenting complaints include pain, a palpable mass, and rarely a pathologic fracture.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      Differentials include giant cell, fibrous dysplasia, aneurysmal bone cyst, unicameral bone cyst, chondromyxoid fibroma, non ossifying fibroma, and potentially malignancies such as fibrosarcoma or osteosarcoma.
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      Radiographically, DF presents as a purely lytic lesion without any mineralized matrix. When seen in long bones, it is oval shaped and usually arises in the metaphysis and extends into the epiphysis and to the subchondral bone plate. DF characteristically has a narrow zone of transition without frank sclerosis. Centrally, the tumor demonstrates a lacelike appearance due to the reticular network of pseudo trabeculae. In recurrent DF, the trabeculation usually appears more dense and irregular.
      • Crim JR
      • Gold RH
      • Mirra JM
      • Eckardt JJ
      • Bassett LW.
      Desmoplastic fibroma of bone: radiographic analysis.
      CT findings are similar to radiographs but can provide a better picture in terms of overall osseous destruction. Magnetic resonance imaging should also be used as an adjunct imaging modality for diagnosis in order to evaluate the extent of soft tissue penetration.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      On MRI, one would typically see decreased signal intensity on T1 weighted images which enhance to increased signal intensity on T2 weighted images
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      . Even though imaging modalities can be helpful in diagnosis of DF, due to its similarities with various other neoplasms, the gold standard for diagnosis of DF remains biopsy.
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      Regarding treatment options for DF, due to a lack of available literature, treatment modalities often are subject to surgeon preference and experience. Wide resection, specifically en bloc resection, is supported by the literature as the treatment of choice, largely due to the high recurrence rates demonstrated by DF. In a 1996 study, Bohm et al reported a recurrence rate of 55-72% after non-resection procedures, and 17% after resection with a 3 year follow-up period. Within those that recurred, 25% progressed to a major amputation as treatment of recurrence. Based on these results, the authors suggested management with marginal or wide resections from the outset, provided it does not result in a significant functional deficit.
      • Böhm P
      • Kröber S
      • Greschniok A
      • Laniado M
      • Kaiserling E.
      Desmoplastic fibroma of the bone. A report of two patients, review of the literature, and therapeutic implications.
      In the present case, as well as in many cases of the calcaneus, anatomic considerations precluded wide resection.
      When lesion site or extent limits wide resection, aggressive intralesional curettage is another viable treatment option. Generally, this method has been reported to show higher rates of recurrence in comparison to wide resections, however some success has been shown. Nishida et al evaluated aggressive intralesional curettage extending beyond the sclerotic perilesional osseous shell with adjunct bone graft. Over a follow up period exceeding 5 years, no complications or recurrences were reported.
      • Nishida J
      • Tajima K
      • Abe M
      • Honda M
      • Inomata Y
      • Shimamura T
      • Shiraishi H
      • Satoh T
      • Ehara S.
      Desmoplastic fibroma. Aggressive curettage as a surgical alternative for treatment.
      Similarly in a 2019 case report, Boyd et al reported no recurrence after curettage and bone grafting of a distal humerus lesion with more than 3 years of follow up.
      • Boyd J
      • Jonard B
      • Weiner S.
      Desmoplastic Fibroma in the Distal Humerus of a 14-Year-Old Boy: A Case Report.
      This is further supported by Stefanidis et al, who detailed no episodes of recurrence following curettage and bone grafting of two simultaneously growing lesions in the ilium and sacrum with more than 6 years of follow up.
      • Stefanidis K
      • Benakis S
      • Tsatalou E
      • Ouranos V
      • Chondros D.
      Computed tomography and magnetic resonance imaging of desmoplastic fibroma with simultaneous manifestation in two unusual locations: a case report.
      While intralesional curettage was utilized in the present case in order to biopsy and mitigate tumor formation, given the extent of the tumor, this did not serve as definitive treatment but rather a form of symptom management. Although not used in the current case report, radiotherapy has been reported as another lesser studied, yet nevertheless successful option in the treatment of DF.
      • Evans S
      • Ramasamy A
      • Jeys L
      • Grimer R.
      Desmoplastic fibroma of bone: A rare bone tumour.
      In conclusion, the above case report details a rare case of DF of the calcaneus in a 22 year-old female managed with curopsy technique biopsy and curettage with backfill with autologous bone graft augmented with allogeneic demineralized bone matrix. Limitations to this study include a relatively short follow-up period of 16 months, in the context of this neoplasm with quite high recurrence rates documented after up to 3 years follow up. Clinical and radiographic presentation regarding DF can be rather nonspecific, and as such it is rarely on the differential until diagnosed with histopathologic report. While DF in the calcaneus is rare and documentation is limited in the literature, cases are important to present and fill this void in the literature as anatomic considerations in this location will likely not allow for en bloc resection. As such, the presentation and management of DF of the calcaneus is critical to present due to the paucity of the literature surrounding this rare osseous neoplasm in the calcaneus, the high recurrence rates, and the high morbidity which would be associated with en bloc resection in this location.

      Financial Disclosures

      None.

      Declaration of competing interests

      The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

      Informed patient consent

      Complete informed consent was obtained from the patient for the publication of this study and accompanying images.

      Acknowledgements

      Eva Patalas, MD and the pathology departments at Cambridge Health Alliance and Massachusetts General Hospital

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