Recurrent glomus tumor of the sellar region with malignant progression

Abstract

Glomus tumors are small, benign mesenchymal neoplasms, the majority of which occur in the dermis or subcutis of the extremities. The single most common site is the subungual region of the fingers, followed by palm, wrist, forearm and foot. The tumor cells resemble modified smooth muscle cells of normal glomus bodies. Glomus tumors, however, have been reported in locations in which the glomus bodies are sparse or even absent, among them patella, nerve, eyelid, liver, gastrointestinal tract, trachea, nose, bone and sella turcica [3, 9]. Glomus tumors usually show a benign clinical course. However, rare malignant cases have been reported [5, 6, 7]. In a recent review on atypical and malignant glomus tumors, Folpe et al. [3] have proposed a classification scheme, encompassing malignant glomus tumors, symplastic glomus tumors, glomus tumors of uncertain malignant potential and glomangiomatosis. Glomus tumors in the sellar region are exceedingly rare and to the best of our knowledge only one case has been reported so far in this location [2]. Here we report the case of an intraand parasellar neoplasm first diagnosed as a benign glomus tumor. Recurrent tumor growth was observed 8 and 10 years after the first surgical intervention and subsequent histology suggested malignant progression of the glomus tumor. In 1991, 9 months after a moderate cervical spine trauma, the 47-year-old female patient noted intermittent diplopia. Ophthalmological examination revealed a right-sided cavernous sinus syndrome with palsy of the occulomotor, trochlear and abducent nerves. Cranial computer tomography and magnetic resonance imaging (MRI) showed an intrasellar mass lesion that extended into the right-sided supraand parasellar regions including the cavernous sinus. Microsurgical tumor resection was performed with a right pterional craniotomy approach. The residual tumor was treated by fractioned radiation therapy (27 fractions with a total dose of 54 Gy). Apart from a persisting right-sided trochlear nerve palsy the clinical history was uneventful till May 1999, when the patient developed a right-sided lid ptosis and an intermittent diplopia. On MRI scans, the tumor was found to have recurred and expanded to the right supraand parasellar regions, now measuring 3 cm in diameter (Fig. 1A). Incomplete tumor resection was performed via a transsphenoidal approach followed by gamma knife radiosurgery with a total dose of 25 Gy. In July 2001 the patient noted further visual impairment and ophthalmological testing revealed loss of visual acuity and visual field defects in the right eye. Endocrinological examination demonstrated panhypopituitarism. Repeated MRI scans again showed tumor growth in the right supraand parasellar region measuring up to 3.5 cm in diameter. The patient underwent right-sided pterional recraniotomy with incomplete tumor resection. Due to progressive visual impairment a further transsphenoidal tumor resection was undertaken in November 2001. Further radiation therapy was initially refused; however, due to progressive tumor growth (Fig. 1B) a targeted radiotherapy using Yttrium-DOTATOC, an Yttrium-labeled somatostatin analogue, was conducted early in 2003. The patient died in October 2003, 12 years after initial manifestation of the tumor. No autopsy was performed. D. Hanggi Department of Neurosurgery, University Hospital Dusseldorf, Dusseldorf, Germany