Carotid body tumors in inhabitants of altitudes higher than 2000 meters above sea level.

BACKGROUND Carotid body tumors (CBTs) are rare. Diagnosis is usually delayed until the tumors reach a critical volume and a mass appears in the neck, which is often asymptomatic. METHODS We reviewed retrospectively the cases with CBT diagnosed from 1965 to 1995 in the Hospital de Oncologia in Mexico City with inhabitants at an altitude higher than 2200 m above sea level to see whether these tumors have the same characteristics as those of inhabitants of countries of lower altitudes. We reviewed the clinical features, diagnostic procedures, therapy, results, and complications. RESULTS There were 120 CBT cases, which represent 79% of the parapharyngeal space tumors diagnosed at our hospital; 116 (96%) were benign and 4 (3.3%) were malignant. Women predominated (89%), and the female-male ratio was 8.3:1. Five patients had multiple paragangliomas, and one had a family history of CBT. Eighty patients (66%) underwent surgery. This was done by cervical approach in 78 cases (97%), and 2 (2.5%) required additional mandibulotomy. There were three deaths due to brain ischemia after carotid ligature. Forty-one patients were followed without treatment, due to advanced age, concomitant diseases, or great volume of the tumor. Median follow-up of these patients was 47 months, during which time no patient reported additional symptoms, accelerated enlargement of the tumor, or metastasis. With a median follow-up of 54 months, only one patient developed local recurrence and three patients developed distant metastasis. CONCLUSIONS We conclude that cases of CBT in our high-altitude population differ significantly from those cases in inhabitants of cities in the U.S. or Europe of less than 1500 m above sea level. Those of high altitudes have an evident female predominance (8.3:1), low rate of bilaterality (5%), and a family history of 1% versus a discrete female predominance (2:1), bilaterality from 10% to 20%, and family history from 7% to 25% in low altitudes. When adequate criteria are used to determine surgical resectability, a complete resection is achieved in 85% of cases, with low or null mortality and high local control.