Phaeochromocytoma (PCC) and paragangliomas (PGL) are neuroendocrine tumours derived from the embryonic neural crest, located either within the adrenal gland or at extra-adrenal sites.
Objective: To study the clinical, biochemical, imaging characteristics, and mutational profile of patients with PCC/PGL treated at our institution.
Methods: We collected data of patients with PCC/PGLs managed at Christian Medical College, Vellore, India over a period of 21 years from 1994 to 2014 by review of medical records.
Results: This retrospective study comprised of 180 subjects with PCC/PGL (52% males and 48% females); with median age at diagnosis of 36 years (range 1672 years). The classical triad of headache, palpitations, and sweating was observed in only 22% of patients. Hypertension was the presenting symptom in 140 (78%) and 62% had headache. Atypical presentations included abdominal pain (42%), fever (6%), and seizures (3%).
Prior to 2008, 24 h urinary vannilyl mandelic acid estimation was done, of which 73% had elevated levels. Urinary metanephrine (uMN) and normetanephrine (uNMN) estimation (from 2008 onwards) revealed elevated uMN alone in 24%, uNMN alone in 12% and both in 64%. The mean largest diameter of the tumours was 6.3 cm (±1.4 cm). 131I-MIBG scan was done in 137 patients (76%), among which 120 subjects (88%) showed increased uptake. Genetic testing for familial PCC/PGL was done in 50 subjects, of whom 16 (32%) had germline mutations in any one of the susceptibility genes RET4, VHL6, SDHB3, and SDHD3. Malignant pheochromocytoma was present in 25 (14%) patients; two of these had SDHB and SDHD mutations. Surgical excision of the tumour/s was carried out in 176 (97%) patients. Of the remaining four patients, one patient was treated with 131I-MIBG therapy in view of metastatic disease, while the other three patients refused surgery.
Conclusion: This is the largest series of PCC/PGL reported till date in Indian patients. It highlights the unique clinical presentations and significant burden of familial cases in an Indian population.