ABSTRACT
BACKGROUND: Medullary thyroid cancer can be subdivided during surgery into tumours with or without a desmoplastic stromal reaction (DSR). DSR positivity is regarded as a sign of disposition to metastasize. The aim of this study was to analyse whether lateral lymph node dissection can be omitted in patients with DSR-negative tumours. METHODS: This was a retrospective cohort study of a prospectively maintained database of patients with medullary thyroid cancer treated using a standardized protocol, and subdivided into DSR-negative and -positive groups based on the results of intraoperative frozen-section analysis. Patients in the DSR-negative group did not undergo lateral lymph node dissection. Long-term clinical and biochemical follow-up data were collected, and baseline parameters and histopathological characteristics were compared between groups. RESULTS: The study included 360 patients. In the DSR-negative group (17.8 per cent of all tumours) no patient had lateral lymph node or distant metastases at diagnosis or during follow-up, and all patients were biochemically cured. In the DSR-positive group (82.2 per cent of all tumours), lymph node and distant metastases were present in 31.4 and 6.4 per cent of patients respectively. DSR-negative tumours were more often stage pT1a and were significantly smaller. The median levels of basal calcitonin and carcinoembryonic antigen were significantly lower in the DSR-negative group, although when adjusted for T category both showed widely overlapping ranges. CONCLUSION: Lymph node surgery may be individualized in medullary thyroid cancer based on intraoperative analysis of the DSR. Patients with DSR-negative tumours do not require lateral lymph node dissection.
Subject(s)
Carcinoma, Neuroendocrine/surgery , Lymph Node Excision , Thyroid Neoplasms/surgery , Aged , Biopsy, Fine-Needle , Calcitonin/blood , Carcinoma, Neuroendocrine/pathology , Female , Humans , Lymph Node Excision/methods , Lymph Node Excision/statistics & numerical data , Male , Middle Aged , Retrospective Studies , Thyroid Neoplasms/pathology , Thyroidectomy/methodsABSTRACT
Postoperative hypoparathyroidism after bilateral thyroid gland surgery or after interventions for recurrence is defined as intact parathyroid hormone levels (iPTH) < 15 pg/ml with simultaneous normal, below normal and markedly decreased serum calcium levels. After bilateral thyroid surgery and after reoperations a single iPTH measurement performed 12-24 h postoperatively can be used to predict parathyroid metabolism. Patients with an iPTH level ≥ 15 pg/ml may be discharged safely, patients with an iPTH < 10 pg/ml must be substituted with calcium and vitamin D and patients with an iPTH between 10 and 15 pg/ml (grey zone) may be discharged if a second measurement 48 h after surgery documents an iPTH ≥ 15 pg/ml. This procedure increases the length of hospital stay. Patients in the (grey zone) must be substituted. The iPTH level and its course determine the necessity, dose and length of calcium and vitamin D substitution.
