Supernumerary parathyroid glands: frequency and surgical significance in treatment of renal hyperparathyroidism.

Supernumerary parathyroid glands (SPGs) are found in 13% of random autopsies. The high incidence of SPGs could explain the persistence or trigger recurrence of renal hyperparathyroidism after surgery. The aim of this study was to assess the frequency and clinical relevance of SPG in patients operated on for renal hyperparathyroidism (HPT). In this retrospective study we reviewed the medical records of 290 patients with renal HPT who were initially treated in our department. We examined the anatomic and pathologic findings during cervical surgical exploration and the outcome of HPT during follow-up. SPGs were identified in 87 patients (30%) during the initial cervicotomy, corresponding to intrathymic parathyroid cell islets (one to four) in 70 cases and to extrathymic SPG in 17 patients. Among 260 patients available for follow-up, 11 experienced persistent HPT (4%), and 34 developed recurrent HPT (13%). A total of 25 patients were reoperated on, and SPGs were responsible for 4 of 8 cases of persistent HPT and 4 of 17 cases of recurrent HPT, representing an overall frequency of 32%. The anatomic distribution of SPGs found during reoperations included thymus, retroesophageal grove, carotid sheath, and mediastinum. SPGs are thus present in 30% of patients with renal HPT and are situated mainly in the thymus. Thymectomy should be performed routinely during the first surgical exploration to prevent recurrences arising from anterior mediastinal glands. SPGs were also responsible for 32% of persistent or recurrent HPT. In that setting, frankly ectopic SPGs are not rare, and preoperative imaging appears highly desirable prior to embarking on surgical reexploration.

Tumour size: the only predictive factor for 131I MIBG uptake in phaeochromocytoma and paraganglioma.

BACKGROUND: 131I Meta-iodobenzylguanidine (131I MIBG) scintigraphy can detect chromaffin tumours with a high specificity but its sensitivity remains limited. In this study, the influence of clinical features and tumour pathology on the results of 131I MIBG of patients with phaeochromocytomas and paragangliomas was examined. METHODS: The records of 104 patients operated on for chromaffin tumours who had pre-operative 131I MIBG were reviewed. Demographic data, clinical features, biochemical results and pathology of tumours were analysed. The size of the tumour was assessed by the three measured diameters of the specimen and its calculated volume. Univariate relationship between tumours' characteristics and the results of 131I MIBG were examined. RESULTS: Out of 119 tumours, 104 (87%) were detected by 131I MIBG. Mean +/- SD largest diameter and volume of the tumours were 6.0 +/- 2.4 cm (range 0.8-11.5 cm) and 68 +/- 74 cm3 (range 0.2-421 cm3). Results of 131I MIBG were significantly correlated with both the largest diameter of the tumour (P < 0.01) and by its volume (P < 0.001). 131I MIBG was negative in 35.5% of tumours < 20 cm3 and in 2.6% of those < 20 cm3. No other criteria were correlated with positive 131I MIBG, including aetiology, pathology or catecholamine secretion pattern. CONCLUSIONS: The result of 131I MIBG scanning in patients with chromaffin tumours is significantly correlated with the size of the tumour.

Effectiveness and limits of preoperative imaging studies for the localisation of pheochromocytomas and paragangliomas: a review of 282 cases. French Association of Surgery (AFC), and The French Association of Endocrine Surgeons (AFCE).

OBJECTIVE: To find out the optimal strategy for the preoperative location of pheochromocytomas and paragangliomas. DESIGN: Retrospective study. PATIENTS: 282 patients operated on for histologically confirmed pheochromocytoma in France between 1980 and 1991, the past decade. MAIN OUTCOME MEASURES: The results of imaging procedures, i.e. computed tomography (CT), (131)I meta-iodobenzylguanidine scintigraphy (MIBG) and magnetic resonance imaging (MRI) were reviewed. RESULTS: Pheochromocytomas were sporadic in 206 (73%). They were unilateral in 189 (67%), bilateral in 54 (19%) and extra-adrenal in 39 (14%). Overall sensitivity of the studies was 89% for CT, 98% for MRI, and 81% for (131)I-MIBG. In unilateral adrenal lesions sensitivity were 100% for CT and MRI, and 88% for (131)I-MIBG; in bilateral lesions 66% for CT, 100% for MRI, and 62% for (131)I-MIBG; in extra-adrenal lesions 64% for CT, 88% for MRI, and 64% for (131)I-MIBG. CONCLUSION: The accuracy with which pheochromocytomas and paragangliomas can be visualized questions nowadays the routine use of abdominal approach. In selected cases of sporadic unilateral chromaffin tumours, a posterior, lateral, or even laparoscopic approach should be considered.

Questionability of the benefits of routine laparotomy as the surgical approach for pheochromocytomas and abdominal paragangliomas.

BACKGROUND: Improvement of preoperative imaging of pheochromocytomas and abdominal paragangliomas may render routine laparotomy questionable as the surgical approach of choice for these lesions. METHODS: We studied the records of 100 patients with chromaffin tumors who underwent abdominal exploration. The disease was familial in 28 patients and was malignant in 19. Seventy-five patients had intraadrenal disease (bilateral in 13). Computed tomography (CT), metaiodobenzylguanidine (MIBG) scintigraphy, and magnetic resonance imaging (MRI) were performed since 1979, 1984, and 1987 in 97, 73, and 43 patients, respectively. False-positive and false-negative results were defined as any discrepancy between imaging results and surgical findings. RESULTS: Overall accuracy of preoperative localization was 85% with CT scan, 77% with MIBG scintigraphy, and 86% with MRI. In unilateral pheochromocytoma, accuracy was 94% with CT scan, 80% with MIBG scintigraphy, and 96% with MRI. When all three studies were performed (n = 38), overall accuracy was 97% and only one extraadrenal tumor in a patient with familial pheochromocytoma was overlooked. CONCLUSIONS: The outstanding accuracy of available imaging techniques questions the strategy of routine laparotomy for sporadic and seemingly benign pheochromocytomas, favoring more elective approaches such as the posterior approach or laparoscopy.

Parathyroid incidentalomas in normocalcemic patients during thyroid surgery.

The aim of this study was to compare the clinical, biochemical, and pathologic findings of normocalcemic patients with macroscopically enlarged parathyroid tissue identified at thyroid surgery with those of patients treated surgically for preoperatively proved primary hyperparathyroidism (PHPT). The records of 28 patients with incidental parathyroid enlargement and 533 patients with PHPT were reviewed to compare age, sex, serum calcium and phosphate, intact parathyroid hormone (iPTH), parathyroid weight, number of diseased glands, cell and histologic types, PTH content, and cure rate. Incidentally found lesions were lighter and developed in younger patients. Biochemistry and pathology found them to be less hyperfunctioning. Sex, number of diseased glands per patient, and cell type were not different. PTH content was low in the incidental lesions. Incidentally discovered enlarged parathyroid glands are mildly hyperfunctioning at the time of discovery. They may represent an early stage of lesion responsible for overt PHPT. In the absence of knowledge concerning their significance and evolution, we recommend that enlarged parathyroids found during the course of a thyroid operation be removed.