Chondromyxoid fibroma of the temporal bone: A rare case report

Abstract

Rationale: Chondromyxoid fibroma (CMF) is a rare form of benign bone tumor and easily misdiagnosed as fibrosarcoma. Hence, to explore the clinical manifestations, diagnostic tests, and therapeutic procedures for temporal bone cartilage myxoid fibroma, it is important to optimize patient treatment and avoid overtreatment. Previous research has discussed cases of CMF, but this paper presents a systematic, complete, and comprehensive introduction of this disease based on this case and related literature.

Patient concerns: A 52-year-old male patient presented with pain in his right ear for 2 years and hearing loss in his right ear with tinnitus for 1 year. The patient had a history of hypertension for 9 years and it was well-controlled.

Diagnosis: A computed tomography (CT) scan of the temporal bone showed an expansive growth on the right temporal bone plate and tympanic plate, presenting as a cloud-like ground glass opaque shadow involving the temporom and ibular joint, middle skull base, and small auditory bones. A magnetic resonance imaging (MRI) of the temporal bone showed a large and irregular soft tissue mass shadow on the right temporal bone plate. The right temporal bone plate was occupied by the lesion, consistent with a bone origin. From the results of the imaging examination of the patient, a lesion occupying the temporal bone in the right ear and mastoiditis in the right middle ear was initially diagnosed.

Interventions: Right ear temporal bone tumor resection and abdominal fat extraction were conducted.

Outcomes: Postoperative pathological results demonstrated myxoid fibroma of the temporal bone cartilage. No recurrence or severe complications were observed in 8 months of follow-up.

Lessons: A finding of myxoid fibroma of the temporal bone cartilage is rare in the clinic. The growth of such tumors is slow. The temporal bone CT and inner ear MRI were helpful in diagnosis. Surgery was the principal treatment.

Figure 1

Results of pure tone audiometry of the CMF patient. (A) Bone conduction: 0-15-35-45 dB HL; air conduction: 88-80-98-100 dB HL (right ear); (B) bone conduction: 0-0-0-35 dB HL; air conduction: 5-5-5-45 dB HL (left ear). CMF = chondromyxoid fibroma.

Figure 2

Temporal bone CT scan and MRI results of the CMF patient: (A) CT axial plane images, (B) CT coronal scan. The results display the right temporal bone plate and tympanic plate presenting with swelling, cloudy flocculent ground-glass opacity, clear boundary, thin bone in the middle of the cranial fossa, low continuity, and involving the temporom and ibular joint. The lesion exhibited hypointensity and presented as an oval soft tissue shadow on the axial T1-weighted image (C, arrow) and T1-weighted image of the coronal aspect (F, arrow). Heterogeneous hyperintensity on the axial T2-weighted image (E, arrow) and T1-enhanced weighted image of the axial position shows ring enhancement (D, arrow). CMF = chondromyxoid fibroma, CT = computed tomography, MRI = magnetic resonance imaging.

Figure 3

Operative picture of the CMF patient. Anterior and superior region of the mastoid process, the posterior and anterior wall of the external auditory canal, and the root of the posterior zygomatic arch were destroyed by the tumor. The mass was bulbous and expanded, protruding forward into the posterior, internal, and lateral m and ibular joint. CMF = chondromyxoid fibroma.

Figure 4

Surgical resection specimen and histopathological results of the CMF patient. (A) Yellowish-white gravel-like bone inside the tumor, with no apparent blood supply, with a small dark gray liquefaction region in the center. (B) The chondrogenic tumor (right ear temporal bone) with clear, granular, calcification, and hemorrhage, which was considered benign. Diffuse calcification and hemorrhage were also found and it was difficult to define the type from morphological and immunohistochemical staining results that did not exclude chondromyxoid fibroma. CMF = chondromyxoid fibroma.

Figure 5

Temporal bone CT of the CMF patient after surgery. (A) The transverse section and (B) the coronal section. CMF = chondromyxoid fibroma, CT = computed tomography.