Peripheral nerve tumors showing glandular differentiation (glandular schwannomas).

Five unusual peripheral nerve tumors of a type originally described by Garrè in 1892 are reported. Each showed unique foci of glandular differentiation. Foci of cartilage were seen in two cases, one of which also showed osteoid. Three of the patients had von Recklinghausen's disease. All but one of the cases showed glands lined by nonciliated cuboidal and/or pseudostratified columnar epithelium bearing clear cytoplasm and demonstrating mucin production. Goblet cells were formed in two cases. While the glandular components appeared malignant in none of the tumors, the spindle-cell element in four of five cases was considered histologically malignant. Three of the patients died with clinical evidence of recurrent or metastatic disease. The first reported examples of this tumor also arose in patients with von Recklinghausen's disease. Data from our five cases and two cases in the literature indicate that glandular schwannomas are potentially malignant tumors with a wide survival span. Follow-up showed that of seven patients, four died with clinical evidence of disease within 7 months to 10 years of their diagnosis. The remaining three were alive and free of disease after 4, 5 and 10 1/2 years. Outcome in a given case is probably related to the degree of malignant change demonstrated by the spindle-cell component of the tumor.