Erika F Brutsaert1, Adam J Gersten, Andrew B Tassler, Martin I Surks. 1. Department of Medicine, Division of Endocrinology (E.F.B., M.I.S.), Department of Pathology (A.J.G.), and Department of Otorhinolaryngology (A.B.T.), Montefiore Medical Center, Bronx, New York 10467.
Abstract
CONTEXT: Calcitonin is a sensitive biomarker that is used for diagnosis and follow-up in medullary thyroid cancer (MTC). In patients with tumors > 1 cm, it is uncommon for preoperative serum calcitonin to be in the normal laboratory reference range in patients with MTC, and even more unusual for serum calcitonin to be undetectable. THE CASE: A 39-year-old woman was found to have a left thyroid nodule on magnetic resonance imaging done for neck pain. Ultrasound and fine-needle aspiration biopsy were performed, and cytopathology was positive for malignant cells. The cells also had features suggestive of a neuroendocrine tumor, and the specimen was immune-stained with calcitonin. There was positive immunoreactivity for calcitonin in isolated cells of the cytospin, highly favoring a diagnosis of MTC. Serum calcitonin was < 2 pg/mL (<6 pg/mL), and serum carcinoembryonic antigen was 3.1 ng/mL (<5.2 ng/mL). Given the low calcitonin levels, procalcitonin was also tested and was elevated at 0.21 ng/mL (< 0.1 ng/mL). The patient subsequently underwent a total thyroidectomy and central and ipsilateral lateral lymph node dissection. Histopathology confirmed a 2.6 × 2.0 × 1.2-cm MTC, with strong, diffuse immunostaining for calcitonin. Postoperatively, serum calcitonin has remained undetectable, carcinoembryonic antigen has remained within the reference range, and procalcitonin has become undetectable. CONCLUSIONS: We present a rare case of a patient with MTC with undetectable preoperative serum calcitonin, whose tumor demonstrated strong, diffuse immunohistochemical staining for calcitonin. We discuss the possible pathogenesis of calcitonin-negative MTC and the challenges in following patients with this condition.
CONTEXT: Calcitonin is a sensitive biomarker that is used for diagnosis and follow-up in medullary thyroid cancer (MTC). In patients with tumors > 1 cm, it is uncommon for preoperative serum calcitonin to be in the normal laboratory reference range in patients with MTC, and even more unusual for serum calcitonin to be undetectable. THE CASE: A 39-year-old woman was found to have a left thyroid nodule on magnetic resonance imaging done for neck pain. Ultrasound and fine-needle aspiration biopsy were performed, and cytopathology was positive for malignant cells. The cells also had features suggestive of a neuroendocrine tumor, and the specimen was immune-stained with calcitonin. There was positive immunoreactivity for calcitonin in isolated cells of the cytospin, highly favoring a diagnosis of MTC. Serum calcitonin was < 2 pg/mL (<6 pg/mL), and serum carcinoembryonic antigen was 3.1 ng/mL (<5.2 ng/mL). Given the low calcitonin levels, procalcitonin was also tested and was elevated at 0.21 ng/mL (< 0.1 ng/mL). The patient subsequently underwent a total thyroidectomy and central and ipsilateral lateral lymph node dissection. Histopathology confirmed a 2.6 × 2.0 × 1.2-cm MTC, with strong, diffuse immunostaining for calcitonin. Postoperatively, serum calcitonin has remained undetectable, carcinoembryonic antigen has remained within the reference range, and procalcitonin has become undetectable. CONCLUSIONS: We present a rare case of a patient with MTC with undetectable preoperative serum calcitonin, whose tumor demonstrated strong, diffuse immunohistochemical staining for calcitonin. We discuss the possible pathogenesis of calcitonin-negative MTC and the challenges in following patients with this condition.
Authors: Else Marie Opsahl; Lars Andreas Akslen; Ellen Schlichting; Turid Aas; Katrin Brauckhoff; Anne Irene Hagen; Alf Frimann Rosenlund; Eva Sigstad; Krystyna K Grøholt; Lars H Jørgensen; Trine Bjøro Journal: Eur Thyroid J Date: 2019-04-29
Authors: Hazel C Levy; Danielle Hulvey; Laura Adamson-Small; Natacha Jn-Simon; Victor Prima; Scott Rivkees; Jacqueline A Hobbs Journal: PLoS One Date: 2020-02-06 Impact factor: 3.240