Intrasellar adenoid cystic carcinoma and papillary mucinous adenocarcinoma: two previously undescribed primary neoplasms at this site.

Most carcinomas involving the sella turcica are metastases. We report two previously undescribed carcinomas that appear to be primary at this site. The first occurred in a 44-year-old woman who presented with hemianopsia. A mass was noted by computed tomography to occupy the sella turcica, from which it appeared to originate. Transphenoidal biopsy showed the tumor to be an adenoid cystic carcinoma with a typical cribriform pattern. The patient died shortly after a subsequent attempt at tumor resection. The second tumor arose in a 55-year-old man who presented with diplopia. Computed tomography showed a mass in the sella turcica that was presumed to be a pituitary adenoma. However, transphenoidal resection revealed a mucinous adenocarcinoma composed of small papillae and glands lined by columnar epithelium. The tumor cells exhibited varying degrees of stratification with prominent interspersed mucin vacuoles. Focal solid areas showed a component of signet ring-type cells. In contrast to the apparent aggressive behavior of the adenoid cystic carcinoma, the papillary mucinous adenocarcinoma appeared much less aggressive, as the second patient was alive and without evidence of disease 5 years later. Both tumors may be derived from epithelial rests within the pituitary gland, either minor salivary gland rests or Rathke's cleft remnants.