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Re-operative Surgery for Pheochromocytoma-Paraganglioma: Analysis of 13 Cases from a Single Institution
Dhiraj John Sonbare1, Deepak Thomas Abraham1, Simon Rajaratnam2
11Department of Endocrine Surgery, Christian Medical College, Vellore, Tamil Nadu 632004 India.
Abstract:
Re-operative adrenal surgery for recurrent pheochromocytoma/paraganglioma (PCC/PGL) is a therapeutic situation not commonly encountered. The recurrence rate of pheochromocytoma is estimated to be 6.1-16.5% of patients from published retrospective series; there are no reports from the Asian continent. A retrospective analysis of the departmental database was performed on patients who had undergone surgery for PCC/PGL from January 2004 to December 2014 at the Christian Medical College Hospital, Vellore, India. Among 99 patients identified during the study period, there were 14 recurrent tumours and 13 patients underwent re-operative surgery. We located eight recurrences on the right side, three on the left side and three in the midline. All 14 recurrences were functioning, and the biochemical analysis as well as imaging studies were positive in 13 of them. The mean duration to recurrence from the time of the primary surgery was 76.3 months (range 6-180 months). Of the 89 patients who underwent their first operation at our centre, 67.4% reported for follow-up for a mean period of 25 months (range 4-132 months). Four of these required re-operation with a recurrence rate of 4.5% (4/89). The open approach was used for all but one of the recurrent tumours. Recurrence following surgery for PCC/PGL is a rarely studied though significant problem. Right adrenal tumour recurrences were most common, and all these recurrences were in the retrocaval region; this typical phenomenon may be dubbed the 'right retrocaval trap'. The reason for this was presumably due to difficult access and inadequate exposure of this area in open and laparoscopic surgery, resulting in incomplete dissection.
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