The CaPTHUS score as predictor of multiglandular primary hyperparathyroidism in a European population

A contemporary analysis of the pre- and intraoperative recognition of multigland parathyroid disease

BACKGROUND

Despite advances in biochemical and radiological identification of parathyroid gland enlargement, primary hyperparathyroidism (PHPT) due to sporadic multigland parathyroid disease (MGPD) remains a perioperative diagnostic dilemma. Failure to recognise MGPD pre- or intraoperatively may negatively impact surgical cure rates and result in persistent PHPT and ongoing patient morbidity.

METHODS

We have conducted a comprehensive review of published literature in attempt to determine factors that could aid in reliably diagnosing sporadic MGPD pre- or intraoperatively. We discuss preoperative clinical features and examine pre- and intraoperative biochemical and imaging findings concentrating on those areas that give practicing surgeons and the wider multi-disciplinary endocrine team indications that a patient has MGDP. This could alter surgical strategy.

CONCLUSION

Biochemistry can provide diagnosis of PHPT but cannot reliably discriminate parathyroid pathology. Histopathology can aid diagnosis between MGPD and adenoma, but histological appearance can overlap. Multiple negative imaging modalities indicate that MGPD may be more likely than a single parathyroid adenoma, but the gold standard for diagnosis is still intraoperative identification during BNE. MGPD remains a difficult disease to both diagnose and treat.

Double ipsilateral parathyroid adenomas, with one supernumerary and ectopic at the same time: a case report

Background

Double adenomas (DA) represents a distinct clinical entity of primary hyperparathyroidism (PHPT). DA may follow various embryologic distribution patterns and could be supernumerary and/or ectopic.

Case presentation

We describe the first case of PHPT which comes as a result of double ipsilateral adenoma, of which one was both ectopic and supernumerary. A 45 year-old Greek male patient with diagnosed PHPT due to a single lower right parathyroid adenoma was admitted to our department for surgical treatment. The preoperative tests (neck US, Sestamibi scan) were conclusive for single gland disease. The patient underwent focused parathyroidectomy. The frozen section revealed a parathyroid adenoma with a slight possibility for parathyroid carcinoma. Ten minutes after the excision, intact PTH (iPTH) dropped >50% related to preoperative values and was within normal range. Right hemithyroidectomy with additional ipsilateral central neck dissection was performed, because of the possibility for parathyroid carcinoma. The final pathology report showed that the first excised tissue proved to be a parathyroid adenoma, while a second subcapsular one and a normal right upper parathyroid gland were also found.

Conclusions

Preoperative localization of DA using routine imaging tests and the utility of intraoperative parathyroid hormone assay are still unreliable in detecting multiple adenomas. Furthermore, a slight possibility of a second and simultaneously supernumerary and ectopic adenoma maybe present. Therefore, it would be advisable to establish the use of more advanced imaging tests (such as 4D-CT, 4D-MRI) or other diagnostic tools when DA are suspected.

Usefulness of the Wisconsin and CaPTHUS indices for predicting multiglandular disease in patients with primary hyperparathyroidism in a southern European population

Background

Focused parathyroidectomy is a safe technique for the treatment of primary hyperparathyroidism. The CaPTHUS score and the Wisconsin index are preoperative diagnostic tools designed to distinguish between single- and multigland disease. The aim of the study is to evaluate the usefulness of these models for predicting multiglandular disease in a European population.

Methods

Retrospective review of a database of patients operated upon for primary hyperparathyroidism at a referral center. The sensitivity, specificity, positive and negative predictive values, and reliability of both scores for the prediction of multiglandular disease, were calculated. Receiver operating characteristic (ROC) curves were constructed to assess the sensitivity and specificity of CaPTHUS score and Wisconsin Index for predicting single-gland disease. A level of P<0.05 was accepted as significant.

Results

Two hundred and eighty-one patients who underwent successful surgery from January 2001 to December 2018 were included. Single-gland disease was detected in 92.5%, and 73.7% had a CaPTHUS score of ≥3. The sensitivity, specificity, positive and negative predictive values of this model for predicting single-gland disease with a score of ≥3 were 76.9%, 66.7%, 96.6%, and 18.9% respectively. The area under the curve value of the CaPTHUS score for predicting single-gland disease was 0.74. A Wisconsin Index >2,000 and an excised gland weight above one gram presented a positive predictive value for single-gland disease of 92.5%.

Conclusions

Despite the good performance of both scales, the established cut-off points did not definitively rule out parathyroid multiglandular disease in our population. In cases with a minimal suspicion of this condition, additional intraoperative techniques must be used, or bilateral neck explorations should be performed.

Evaluation of Wisconsin and CaPTHUS Indices Usefulness for Predicting Monoglandular and Multiglandular Disease in Patients with Primary Hyperparathyroidism through the Analysis of a Single-Center Experience

BACKGROUND

The main challenge for treating primary hyperparathyroidism (PHPT) is to understand if it is caused by a single adenoma (80-85% of the cases) or by a multiglandular disease (15-20%), both preoperatively and intraoperatively. For this reason, some preoperative scores were proposed in the literature, to perform focused parathyroidectomy, avoiding intraoperative parathormone assay (ioPTH). The most known are the CaPTHUS test and the Wisconsin index. We applied them to our experience.

METHODS

A retrospective cohort study on 462 patients referred for parathyroidectomy to Thyroid and Parathyroid Unit at Santi Paolo e Carlo Hospital, Milan, Italy, from 2011 to 2021. Only patients affected with benign PHPT and neck ultrasound performed at our institution were included. Both patients for whom preoperative imaging agreed with the localization of a single diseased parathyroid and those with only ultrasound or scintigraphy positive for parathyroid localization underwent Mini-Invasive Video-assisted parathyroidectomy. In all cases, ioPTH assay was performed. The conversion to bilateral neck exploration was decided based on the drop in ioPTH. CaPTHUS score and the Wisconsin index (Win) were applied to the series. CaPTHUS score ≥3 and Win index >1600, according to the original studies of the literature, were considered at high probability of monoglandular disease. Outcomes in these two groups were examined.

RESULTS

236 patients were eligible for the study. The pathology resulted in multiglandular disease in 24 patients (10.2%). Among these, 18 (75.0%) obtained a CaPTHUS score ≥3, and 20 (83.3%) had a Win index>1600. Intraoperative PTH allowed to identify multiglandular disease in 16 of 18 cases with CaPTHUS ≥3 and in 18 of 20 cases with win >1600, who could have been lost, based only on the results of these 2 tests.

CONCLUSION

Based on our experience, CaPTHUS test and Wisconsin index were not so useful in predicting multiglandular disease as ioPTH.

The surgical management of sporadic primary hyperparathyroidism

Sporadic primary hyperparathyroidism (pHPT) is the commonest cause of hypercalcaemia in the ambulatory population. It has a female preponderance and its incidence is increasing. In 85% of cases it is caused by a single parathyroid adenoma, with four gland hyperplasia in up to 20%. Parathyroidectomy is the only cure and bilateral neck exploration remains the gold standard to achieve this. Several adjuncts have been developed to improve success rates or limit the extent of surgery. Pre-operative localisation permits planned targeted surgery. Ultrasound scanning and scintigraphy are the most commonly employed, although 4DCT has become a useful modality in complex cases. However, excellent rates of biochemical cure can be achieved in specialist centres when pre-operative imaging is negative. Pre-operative prediction models and intra-operative parathyroid hormone (ioPTH) assist, with high sensitivity, to predict single gland disease. Reoperations present a major challenge to the endocrine surgeon.

Current predictive models do not accurately differentiate between single and multi gland disease in primary hyperparathyroidism: a retrospective cohort study of two endocrine surgery units

Background Minimally invasive parathyroidectomy (MIP) for primary hyperparathyroidism is dependent upon accurate prediction of single-gland disease on the basis of preoperative imaging and biochemistry. The aims of this study were to validate currently available predictive models of single-gland disease in two UK cohorts and to determine if these models can facilitate MIP. Methods This is a retrospectively cohort study of 624 patients who underwent parathyroidectomy for primary hyperparathyroidism in two centres between July 2008 and December 2013. Two recognised models: CaPTHUS (preoperative calcium, parathyroid hormone, ultrasound, sestamibi, concordance imaging) and Wisconsin Index (preoperative calcium, parathyroid hormone) were validated for their ability to predict single-gland disease. Results The rates of single- and multi-gland disease were 491 (79.6%) and 126 (20.2%), respectively. Cure rates in centres 1 and 2 were 93.2% and 93.8%, respectively (P = 0.789). The positive predictive value (PPV) of CaPTHUS score . 3 in predicting single-gland disease was 84.6%, compared with 100% in the original report. CaPTHUS . 4 and 5 had a PPV of 85.1 and 87.1, respectively. There were no differences in Wisconsin Index (WIN) between patients with single- and multi-gland (P = 0.573). A WIN greater than 1600 and weight of excised gland greater than 1 g had a positive predictive value of 86.7% for single-gland disease. Conclusions The use of CaPTHUS and WIN indices without intraoperative adjuncts (such as IOPTH) had the potential to result in failure to cure in up to 15% (CaPTHUS) and 13% (WIN) of patients treated by MIP targeting a single enlarged gland.