Language dominance in patients with early childhood tumors near left hemisphere language areas

Rationale Language function often develops in the right hemisphere following an acute left hemispheric insult in early childhood. Little is known, however, about lateralization of language function in patients with early childhood tumors near potential left hemisphere language areas. Issues of language dominance are important in the strategy for resection of left temporal and frontal tumors. Methods We studied 12 patients who had determination of hemispheric language dominance by the intracarotid amobarbital procedure prior to resection of a left inferolateral frontal or left mid or posterior temporal tumor that (1) was near a classic language area and (2) first manifested with partial seizures by age 6 years (mean, 3.7). Results Hemispheric language dominance was left in 10 patients (83%), right in one patient, and bilateral in one patient. Six patients with left temporal tumors had localization of Wernicke's area with cortical stimulation, and in five the language area was posterior to the tumor. In one patient, the tumor infiltrated Wernicke's area. Eleven of the 12 patients had complete tumor resection (mean age at operation, 11.8 years) and were seizure-free at follow-up (mean, 3.1 years). Neuropsychological testing showed a tendency for improved language function after operation, and no patient had new overt language deficits. Conclusions Early low-grade left frontal and temporal tumors usually did not result in transfer of language dominance to the contralateral hemisphere. Tumors may grow slowly along with the developing brain in young children, with continued left hemisphere language development in regions separate from the neoplasm. Successful tumor resection can be accomplished, but it may require cortical stimulation for localization and sparing of nearby language areas.