Radiologic assessment of retropharyngeal node involvement in oropharyngeal carcinomas stratified by HPV status.

Radiation of retropharyngeal nodes (RPN) results in increased toxicities. This study assessed characteristics associated with RPN involvement in 165 oropharynx cancer patients. Factors associated with involvement were stage N2c-3 disease and stage N2b disease with either advanced T-stage, ⩾3 involved cervical LN, and ⩾1 involved contralateral LN, or lateral/posterior subsites.

Pineal parenchymal tumor of intermediate differentiation: imaging spectrum of an unusual tumor in 11 cases.

INTRODUCTION: Pineal parenchymal tumor of intermediate differentiation (PPTID) was recognized in the 2007 World Health Organization (WHO) classification as a new pineal parenchymal neoplasm, intermediate in malignancy (WHO grade II or III) between pineocytoma (grade I) and pineoblastoma (grade IV). The imaging spectrum of this new tumor has not been previously delineated. We describe the imaging spectrum in 11 pathologically proven PPTIDs and identify findings that may suggest the preoperative diagnosis of this newly recognized entity. METHODS: Electronic medical records over the last 9 years and teaching files between the years 1985 and 1995 were searched for atypical pineal lesions. Additional cases were added from the teaching files of contributing authors. RESULTS: Imaging studies in nine patients (9/11) showed bulky, aggressive pineal region masses with local brain invasion; two patients (2/11) demonstrated circumscribed pineal masses. Two patients had spinal metastases at presentation. On computed tomography (CT), five patients had classic "exploded" calcifications characteristic of pineal parenchymal tumors. All tumors were heterogeneously hypointense on T1WIs and heterogeneously hyperintense on T2WIs. Post-contrast scans showed marked heterogeneous (10/11) or uniform (1/11) enhancement. Cystic foci were identified in eight cases. Intratumoral hemorrhage was present in one case. CONCLUSION: While no singular neuroimaging feature is pathognomonic of PPTID, these tumors are usually larger, demonstrate local invasion, and appear much more heterogeneous than pineocytoma. Because PPTIDs have a higher grade and increased potential for recurrence as compared to pineocytomas, it is important to consider this diagnosis as shorter follow-up, and adjuvant therapy may be indicated in selected cases.

Opposite cerebral dominance for reading and sign language.

We present a case of right hemispheric dominance for sign language but left hemispheric dominance for reading, in a left-handed deaf patient with epilepsy and left mesial temporal sclerosis. Atypical language laterality for ASL was determined by preoperative fMRI, and congruent with ASL modified WADA testing. We conclude that reading and sign language can have crossed dominance and preoperative fMRI evaluation of deaf patients should include both reading and sign language evaluations.

Pilomyxoid astrocytoma: neuroimaging with clinicopathologic correlates in 4 cases followed over time.

Pilomyxoid astrocytoma (PmA) is a recently identified tumor type characteristically located in the hypothalamus and occurring in young children (<2 y). PmAs were formerly included in large series of pilocytic astrocytomas (PA) until it was realized in 1999 that this differing phenotype tended to manifest a more aggressive biologic course. PmA is defined by its pathologic features of a monomorphous architectural pattern, abundant myxoid background, and absence of features seen in classic PA. We present 4 histologically definite cases of PmA seen at our institution over a minimum 5-year follow-up time: one was rapidly fatal after initial treatment and 2 recurred during therapy. No singular neuroimaging feature can reliably diagnose PmA. However, PmAs tend to be solid, are more commonly necrotic and show extension of abnormal signal intensity into adjacent structures. Cysts, calcification, and perilesional edema are more common in classic PA. Serial neuroimaging in PmA shows early progression of predominantly solid, and later progression of predominantly cystic component. Radiologists should consider this diagnosis particularly in young children with hypothalamic tumors that lack the typical cystic appearance seen in PA.