Otology & Neurotology 36:e119Ye120 Ó 2015, Otology & Neurotology, Inc.
Temporal Bone Histopathology Case of the Month
Desmoplastic Fibroma of the Temporal Bone *Ananya Majumder, *Sachin Gupta, †Paul Friedman, and *Brandon Isaacson *Departments of OtolaryngologyYHead and Neck Surgery and ÞPathology, University of Texas Southwestern Medical Center, Dallas, Texas, U.S.A
Desmoplastic fibroma of bone is a benign but locally aggressive osseous tumor, most commonly found in long bones. We describe an unusual presentation, highlighting the importance of considering these lesions in the differential diagnosis of fibro-osseous lesions of the temporal bone. Although hormonal regulation has been conjectured, treatment remains complete surgical excision.
and simultaneous placement of a bone-anchored hearing aid. He has done well since that time with no evidence of recurrence 18 months after primary resection.
CASE PRESENTATION A 13-year-old male patient presented with a 9-month history of right aural fullness, progressive hearing loss, and pulsatile tinnitus. On examination, he had a stenotic, slit-like external auditory canal preventing visualization of the tympanic membrane. The patient reported a history of transient facial paresis. An audiogram showed a maximal conductive loss on the affected side. Facial nerve electroneuronography revealed normal facial nerve function. CT imaging revealed a large fibro-osseous lesion involving the entire lateral aspect of the right temporal bone, narrowing both the vertical fallopian canal and the lateral external auditory canal. There was no involvement of the otic capsule or internal auditory canal. MRI revealed an enhancing mass involving the lateral and superior aspects of the right temporal bone adjacent to the temporal lobe. Finally, a technetium nuclear medicine bone scan showed increased uptake in the area of interest. The patient was taken to the operating room for an open biopsy. Intraoperatively, the mass appeared densely fibrotic with irregular appearance of the involved bone. Final pathology revealed a paucity of spindle cells in a background of abundant collagenous tissue, consistent with desmoplastic fibroma (Fig. 1). He then underwent a complete resection, which was performed via infratemporal fossa approach with overclosure of the ear canal Address correspondence and reprint requests to Brandon Isaacson, M.D., FACS, Department of OtolaryngologyYHead and Neck Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9035, U.S.A.; E-mail: [email protected] The authors report no conflicts of interest.
FIG. 1. A, Low power view (hematoxylin and eosin, original magnification 4) of mastoid contents showing bony trabeculae with surrounding bland spindle cells (fibroblasts) without atypia or mitoses in a background of collagen fibers. B, High power view (hematoxylin and eosin, original magnification 20).
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Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
e120
A. MAJUMDER ET AL. DISCUSSION
Desmoplastic fibroma of bone is a rare tumor, comprising only 0.06% of all osseous neoplasms. They usually occur in the first three decades of life and show equal predilection for both sexes. Although histologically benign, they can be locally aggressive. For this reason, they have been placed in an intermediate category between benign and malignant tumors by the World Health Organization (1). These tumors typically occur in the metaphyses of long bones and in the mandible. Desmoplastic fibroma in the temporal bone was first described in 1990, with only a handful of reports in the literature thereafter. These tumors most commonly present with aural fullness and progressive hearing loss, and occasionally with ipsilateral temporal swelling and deformity (1Y3). Grossly, these lesions are grayish-white and rubbery in texture. Histologically, they are characterized by few scattered spindle cells, or fibroblasts with elongated cytoplasm and bland ovoid nuclei, in a background of copious collagenous stroma. They are differentiated from fibrosarcoma and fibrous dysplasia due to a lack of cellularity, pleomorphism, and mitotic activity (1,2,4). Soft tissue desmoids differ clinically, as they display late osseous infiltration. Radiologically, the lytic bone cyst appearance of desmoplastic fibromas can appear similar to fibrous dysplasia, giant cell tumor, chondrosarcoma, and aneurysmal bone cyst.
Desmoplastic fibromas have a predilection for occurring in young age groups, and thus hormonal regulation has been considered as part of the pathogenesis. This is supported by the fact that desmoid tumors, the soft tissue counterpart to these lesions, are often responsive to tamoxifen (3). Several temporal bone desmoplastic fibromas have been tested for estrogen and progesterone receptors with none showing positivity (2,3). There is mention of a case being treated with tamoxifen with a good early response; however, it is unclear why this modality was chosen (2). The treatment of choice for desmoplastic fibroma of the temporal bone remains surgical resection. Patients must be counseled, however, that local recurrence rates may be as high as 30% (2), highlighting the importance of complete removal at the time of initial operation.
REFERENCES 1. Rabin D, Ang LC, Megyesi J, et al. Desmoplastic fibroma of the cranium: case report and review of the literature. Neurosurgery 2003;52:950Y4. 2. Pensak M, Nestok BR, vn Loveren H, et al. Desmoplastic fibroma of the temporal bone. Am J Otol 1997;18:627Y31. 3. Dutt S, Irving R. Pathology in focus: desmoplastic fibroma of the temporal bone. J Laryngol Otol 2000;113:314Y7. 4. Bo¨hm P, Kro¨ber S, Greschniok A, et al. Desmoplastic fibroma of the bone. Cancer 1996;78:1011Y23.
Otology & Neurotology, Vol. 36, No. 7, 2015
Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
Temporal Bone Histopathology Case of the Month
Desmoplastic Fibroma of the Temporal Bone *Ananya Majumder, *Sachin Gupta, †Paul Friedman, and *Brandon Isaacson *Departments of OtolaryngologyYHead and Neck Surgery and ÞPathology, University of Texas Southwestern Medical Center, Dallas, Texas, U.S.A
Desmoplastic fibroma of bone is a benign but locally aggressive osseous tumor, most commonly found in long bones. We describe an unusual presentation, highlighting the importance of considering these lesions in the differential diagnosis of fibro-osseous lesions of the temporal bone. Although hormonal regulation has been conjectured, treatment remains complete surgical excision.
and simultaneous placement of a bone-anchored hearing aid. He has done well since that time with no evidence of recurrence 18 months after primary resection.
CASE PRESENTATION A 13-year-old male patient presented with a 9-month history of right aural fullness, progressive hearing loss, and pulsatile tinnitus. On examination, he had a stenotic, slit-like external auditory canal preventing visualization of the tympanic membrane. The patient reported a history of transient facial paresis. An audiogram showed a maximal conductive loss on the affected side. Facial nerve electroneuronography revealed normal facial nerve function. CT imaging revealed a large fibro-osseous lesion involving the entire lateral aspect of the right temporal bone, narrowing both the vertical fallopian canal and the lateral external auditory canal. There was no involvement of the otic capsule or internal auditory canal. MRI revealed an enhancing mass involving the lateral and superior aspects of the right temporal bone adjacent to the temporal lobe. Finally, a technetium nuclear medicine bone scan showed increased uptake in the area of interest. The patient was taken to the operating room for an open biopsy. Intraoperatively, the mass appeared densely fibrotic with irregular appearance of the involved bone. Final pathology revealed a paucity of spindle cells in a background of abundant collagenous tissue, consistent with desmoplastic fibroma (Fig. 1). He then underwent a complete resection, which was performed via infratemporal fossa approach with overclosure of the ear canal Address correspondence and reprint requests to Brandon Isaacson, M.D., FACS, Department of OtolaryngologyYHead and Neck Surgery, University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd, Dallas, TX 75390-9035, U.S.A.; E-mail: [email protected] The authors report no conflicts of interest.
FIG. 1. A, Low power view (hematoxylin and eosin, original magnification 4) of mastoid contents showing bony trabeculae with surrounding bland spindle cells (fibroblasts) without atypia or mitoses in a background of collagen fibers. B, High power view (hematoxylin and eosin, original magnification 20).
e119
Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
e120
A. MAJUMDER ET AL. DISCUSSION
Desmoplastic fibroma of bone is a rare tumor, comprising only 0.06% of all osseous neoplasms. They usually occur in the first three decades of life and show equal predilection for both sexes. Although histologically benign, they can be locally aggressive. For this reason, they have been placed in an intermediate category between benign and malignant tumors by the World Health Organization (1). These tumors typically occur in the metaphyses of long bones and in the mandible. Desmoplastic fibroma in the temporal bone was first described in 1990, with only a handful of reports in the literature thereafter. These tumors most commonly present with aural fullness and progressive hearing loss, and occasionally with ipsilateral temporal swelling and deformity (1Y3). Grossly, these lesions are grayish-white and rubbery in texture. Histologically, they are characterized by few scattered spindle cells, or fibroblasts with elongated cytoplasm and bland ovoid nuclei, in a background of copious collagenous stroma. They are differentiated from fibrosarcoma and fibrous dysplasia due to a lack of cellularity, pleomorphism, and mitotic activity (1,2,4). Soft tissue desmoids differ clinically, as they display late osseous infiltration. Radiologically, the lytic bone cyst appearance of desmoplastic fibromas can appear similar to fibrous dysplasia, giant cell tumor, chondrosarcoma, and aneurysmal bone cyst.
Desmoplastic fibromas have a predilection for occurring in young age groups, and thus hormonal regulation has been considered as part of the pathogenesis. This is supported by the fact that desmoid tumors, the soft tissue counterpart to these lesions, are often responsive to tamoxifen (3). Several temporal bone desmoplastic fibromas have been tested for estrogen and progesterone receptors with none showing positivity (2,3). There is mention of a case being treated with tamoxifen with a good early response; however, it is unclear why this modality was chosen (2). The treatment of choice for desmoplastic fibroma of the temporal bone remains surgical resection. Patients must be counseled, however, that local recurrence rates may be as high as 30% (2), highlighting the importance of complete removal at the time of initial operation.
REFERENCES 1. Rabin D, Ang LC, Megyesi J, et al. Desmoplastic fibroma of the cranium: case report and review of the literature. Neurosurgery 2003;52:950Y4. 2. Pensak M, Nestok BR, vn Loveren H, et al. Desmoplastic fibroma of the temporal bone. Am J Otol 1997;18:627Y31. 3. Dutt S, Irving R. Pathology in focus: desmoplastic fibroma of the temporal bone. J Laryngol Otol 2000;113:314Y7. 4. Bo¨hm P, Kro¨ber S, Greschniok A, et al. Desmoplastic fibroma of the bone. Cancer 1996;78:1011Y23.
Otology & Neurotology, Vol. 36, No. 7, 2015
Copyright © 2015 Otology & Neurotology, Inc. Unauthorized reproduction of this article is prohibited.
