PMC5862672_01
Sagittal view of radiotherapy planning computerized tomography (A) depicting the original gross tumor volume (colour wash) and 70 Gy isodose line encompassing the anterior components of C2-C3 vertebral bodies where osteomyelitis occurred. Sagittal (B) and axial (C) fat-saturated T2-weighted magnetic resonance images show evolving tumor ulceration along the posterior oropharyngeal wall (arrows).
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HPV-negative oropharyngeal carcinoma and the patient was offered definitive concurrent CRT (IMRT 70 Gy in 35 fractions [Fig. 1A] and elective bilateral neck irradiation (not shown in the figure) with concurrent high-dose cisplatin [100 mg/m2] on weeks 1, 4, and 7). After completion of radiotherapy, the patient had a good response to treatment on imaging. although, a flexible nasopharyngoscopy showed a persisting area of ulceration along the posterior pharyngeal wall mucosa [Fig. 1B and C].
Magnetic Resonance Image (MRI) demonstrates edema in the C2-C3 vertebrae with intact endplate margins (A). Loss of disc space height between C2 and C3 with endplate irregularity is evident and mild pressure on the subarachnoid space from an anterior epidural phlegmon has developed 3 months later (B). Enhancing epidural phlegmon (long arrow) is also evident in the anterior epidural space (C) and epidural phlegmon surrounding the vertebral arteries (short arrows) (D). The findings are typical of a discitis-osteomyelitis complex.
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MRI showed a slight increase in the extent of ulceration as well as new abnormal signal changes in the C2 and C3 vertebral bodies [Fig. 2A]. A repeat MRI performed after three months showed further progression of the ulcerated area as well as increased marrow abnormalities in the cervical spine with development of an epidural collection abutting the anterior margin of the spinal cord [Fig. 2B-D].
PMC5862672_02
Axial (A) and Coronal (B) MRI imaging shows nasopharyngeal carcinoma with extension into the right cavernous sinus, juxtaposed to the pituitary gland. The region of osteomyelitis was encompassed in the 66 Gy (inner thin line) radiotherapy volume (C).
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MRI and positron emission tomography (PET) imaging revealed an extensive nasopharyngeal mass involving the entire nasopharynx with extension through the foramen ovale and foramen lacerum into the right cavernous sinus juxtaposed to the pituitary gland [Fig. 3A and B]. The patient was treated with a course of high-dose concurrent CRT consisting of 70 Gy in 35 fractions to all gross disease [Fig. 3C] and elective radiotherapy to adjacent tissues and both necks (not shown in figure), delivered with concurrent cisplatin (100 mg/m2 on weeks 1, 4, and 7) and adjuvant cisplatin and 5-fluourouracil for 3 cycles. The disease responded successfully with recovery of cranial nerve findings and resolution of the EBV titres on all subsequent assays.
Follow up contrast enhanced axial T1 weighted (A and B) and fat-saturated axial T2 weighted image (C) shows diffuse enhancement of the right external auditory canal and right masticator space. There is tissue ulceration and necrosis in the right posterolateral nasopharynx (white arrow). The T2 image shows a preservation of the tissue planes in the right masticator space supporting an inflammatory process rather than tumor infiltration. An indium-111 white blood cell scan (D) shows uptake in the region of the right masticator space, nasopharynx and right central bony skull base. These findings also favor an infectious process.
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Mild enhancement and edema was also seen in the left nasopharynx. [Fig. 4A-C]. A three-phase bone scan and indium white blood cell scan revealed focal leukocytic activity involving the masticator space and right aspect of the skull base in keeping with a diagnosis of osteomyelitis [Fig. 4D].