Objective: To describe the new L95P mutation of the paraganglioma 1 gene for glomus tumors in a Dutch paraganglioma 1 family with six affected family members and to report the clinical findings and results of treatment in nine glomus tumors with a maximum follow-up of 34 years.
Setting: Tertiary referral centers.
Results: Mutation analysis of the SDHD gene of paraganglioma 1 showed the L95P mutation in six affected family members and two nonaffected carriers protected from becoming affected by genomic imprinting. In six affected family members, nine glomus tumors (five glomus caroticum tumors, two glomus vagale tumors, and two glomus jugulare tumors) were traced. The ages at presentation varied from 25 to 61 years. In two of six affected family members with a total of four tumors, all the tumors were traced in the extended family study, using magnetic resonance imaging; at that time these tumors were silent. After radiotherapy in one patient at the age of 34 years, a T4 planocellular carcinoma of the tongue occurred within the previous radiation field 27 years later, when the patient was 61 years old. Volume measurements of three untreated glomus tumors (two glomus vagale tumors, one glomus caroticum tumor) during 25 months showed an increase in two tumors (left glomus caroticum, left glomus vagale tumor) and a decrease in one tumor (right glomus vagale tumor). Surgery to remove two bilateral and one unilateral glomus caroticum tumors was successful. A wait-and-see policy is being applied to two glomus vagale tumors.
Conclusions: In family members of paraganglioma 1 patients, mutation analysis can be used to make an early diagnosis of glomus tumors. Radiotherapy may have induced a carcinoma. Modalities of treatment can include a wait-and-see policy. Long-term follow-up studies on the natural course of glomus tumors are needed to improve decisions about treatment modalities.