Medullary thyroid cancer outcomes in patients with undetectable versus normalized postoperative calcitonin levels.

BACKGROUND: Calcitonin (Ct) is a sensitive diagnostic biomarker and one of the most important prognostic factors in medullary thyroid cancer (MTC). This study aimed to evaluate progression-free survival and recurrence rates of MTC associated with undetectable compared with normalized serum Ct levels after surgery. METHODS: This retrospective observational study included patients operated for MTC at the Digestive and Endocrine Surgery Department of Lyon Sud Hospital Centre between 2000 and 2019. Clinical and pathological factors were correlated with postoperative Ct concentrations. Undetectable and normalized Ct concentrations were defined as below 2 pg/ml and 2-10 pg/ml respectively. RESULTS: Overall, 176 patients were treated for MTC, and 127 were considered biochemically cured after surgery. Of these, 24 and 103 had normalized and undetectable Ct concentrations respectively. Patients with Ct level normalization had a 25 per cent risk of disease recurrence, compared with 3 per cent in patients with undetectable Ct levels after surgery. The presence of metastasis in two or more compartments was predictive of failure to achieve undetectable Ct concentrations after surgery and an increased risk of recurrence. CONCLUSION: Among patients with biochemically cured MTC, those with undetectable or normalized Ct concentrations after surgery had different risks of recurrence. Simply assessing postoperative Ct normalization can be falsely reassuring, and long-term follow-up is needed. LAY SUMMARY: Calcitonin (Ct) is a sensitive diagnostic biomarker and one of the most important prognostic factors for medullary thyroid cancer outcomes; however, the significance of postoperative Ct levels remains controversial. This study evaluated the differences between normal and undetectable postoperative Ct levels in patients who had undergone surgical treatment for medullary thyroid cancer. Patients who experienced postoperative Ct level normalization had a higher risk of disease recurrence than those with undetectable Ct levels after surgery.

Calcitonin (Ct) is a sensitive diagnostic biomarker and one of the most important prognostic factors for medullary thyroid cancer outcomes; however, the significance of postoperative Ct levels remains controversial. This study evaluated the differences between normal and undetectable postoperative Ct levels in patients who had undergone surgical treatment for medullary thyroid cancer. Patients who experienced postoperative Ct level normalization had a higher risk of disease recurrence than those with undetectable Ct levels after surgery.

Autofluorescence pattern of parathyroid adenomas.

BACKGROUND: Primary hyperparathyroidism (pHPT) is a common endocrine pathology, and it is due to a single parathyroid adenoma in 80-85 per cent of patients. Near-infrared autofluorescence (NIRAF) has recently been used in endocrine surgery to help in the identification of parathyroid tissue, although there is currently no consensus on whether this technique can differentiate between normal and abnormal parathyroid glands. The aim of this study was to describe the autofluorescence pattern of parathyroid adenoma in pHPT. METHODS: Between January and June 2019, patients with pHPT who underwent surgical treatment for parathyroid adenoma were enrolled. Parathyroid autofluorescence was measured. RESULTS: Twenty-three patients with histologically confirmed parathyroid adenomas were included. Parathyroid adenomas showed a heterogeneous fluorescence pattern, and a well defined autofluorescent 'cap' region was observed in 17 of 23 specimens. This region was on average 28 per cent more fluorescent than the rest of the adenoma, and corresponded to a rim of normal histological parathyroid tissue (sensitivity and specificity 88 and 67 per cent respectively). After resection, all patients were treated successfully, with normal postoperative values of calcium and parathyroid hormone documented. CONCLUSION: Parathyroid adenomas show a heterogeneous autofluorescence pattern. Using NIRAF imaging, the majority of specimens showed a well defined autofluorescent portion corresponding to a rim of normal parathyroid tissue. Further studies should be conducted to validate these findings.