Is three-gland-or-less parathyroidectomy a clinical failure for secondary hyperparathyroidism?

Objective: To compare the clinical and biochemical outcomes between adequate and inadequate parathyroidectomies in patients with chronic renal failure.

Material And Methods: All secondary hyperparathyroidism patients who were previously operated in the Marmara University Hospital Breast and Endocrine Surgery Unit were planned to be included in the study. Patients were divided into two groups according to their extent of surgery: "adequate" and "inadequate" surgery groups. "Adequate surgery" was regarded as either subtotal (3½) or total parathyroidectomy. Removing fewer than 3½ parathyroids was defined as "inadequate surgery." Demographic, preoperative clinical symptoms, and their severity, as well as biochemical (e.g., tCa, PTH) findings, were recorded. Patients were followed monthly. The course of biochemical findings (tCa, PTH, P, ALP) and symptoms (by a scoring system of 1-4) was determined by comparing preoperative findings to those at the patient's last follow-up. Primary outcome of the study was treatment failure (biochemical persistence/recurrence) rates in both study cohorts. Secondary outcomes of the study were the levels of biochemical findings and improvement rates of clinical symptoms after parathyroidectomy, as well as complication rates related to the initial surgery in each surgery cohort.

Results: Forty-two patients with secondary hyperparathyroidism who underwent parathyroidectomy were included into the study. Twenty-six were male and 16 were female. Median age was 46. Forty (95%) patients had at least one symptom as the indication for surgery, whereas only 2 (5%) patients were asymptomatic, but biochemical findings were the indication. Twenty-two (52%) patients underwent adequate operation, whereas 20 (48%) patients had inadequate operation. Mean follow-up duration after initial parathyroidectomy was 60 [3-244] months. Significantly more patients (n=15; 75%) in the inadequate surgery group had biochemical persistence/recurrence when compared with those (n=8; 36%) who underwent adequate surgery (OR [odds ratio] 5.25; 95% CI 1.38-19.93; p=0.012). However, symptom improvement rates were similar in both adequate and inadequate surgery groups.

Conclusion: Although there is high biochemical treatment failure after inadequate parathyroidectomy in patients with renal hyperparathyroidism, clinical symptom improvement rates are also surprisingly high in this patient group. On the other hand, the adequate surgery group also had an increased biochemical failure rate well above expected in longer follow-ups.