Determinants of tumor size and growth in vestibular schwannomas.

OBJECT: This study was undertaken to analyze factors associated with the size of unilateral vestibular schwannomas (VSs). METHODS: A retrospective analysis of an unselected and sequential series of 433 patients with unilateral VSs was conducted. Tumor size was defined by the largest dimension of the tumor in the cerebellopontine angle, and the size was tested for a relationship with patient age and sex. In a subgroup of 231 patients in whom data were available, tumor size was also tested for a relationship with tumor cysts or the absence of an internal auditory canal (IAC) component. Some patients underwent a period of surveillance with serial imaging studies to monitor for tumor growth. Data from these patients, excluding those with cystic tumors, were analyzed to see if tumor growth was related to patient age, sex, or tumor size. CONCLUSIONS; Larger tumors were found in younger patients, in females, in the subgroup of cystic tumors, and in patients in whom there was no tumor component in the IAC. The probable explanations for these larger tumors are a faster growth rate and/or a delay in symptom onset. When untreated tumors are managed with observation, measurable growth is more often seen in larger tumors, although smaller tumors have a faster relative growth rate than larger ones.

Sinonasal mucosa-associated lymphoid tissue lymphoma.

Mucosa-associated lymphoid tissue (MALT) is a specialized form of lymphoid tissue that may be acquired at sites in response to chronic inflammation. Most low-grade, B-cell, non-Hodgkin lymphomas that occur at extranodal sites derive from acquired MALT. Confusing and overlapping terms have been used to describe these lymphomas, but immunohistochemical advances now allow more precise subtyping. Our review of the literature yielded only 2 previous reports of sinonasal MALT-derived lymphoma, and we report an additional case in a patient with a history of chronic sinusitis. Current developmental theories of MALT-derived lymphomas are discussed. In addition, we review the clinical, histologic, and immunophenotypic features of MALT-derived lymphomas.