title: One-step nucleic acid amplification testing in medullary thyroid cancer lymph nodes: a case series.
abstract: BACKGROUND
  Locoregional relapse in medullary thyroid cancer (MTC) may be caused by nodal micrometastases. Medullary thyroid cancer lymph nodes have not yet been evaluated by one-step nucleic acid amplification (OSNA). Therefore, the aim of this study was to detect MTC cells by OSNA in cervical lymph nodes and compare the obtained outcomes with conventional histopathology.
  
  
  METHODS
  Twenty-one randomized, unenlarged lymph nodes from 5 patients with MTC were examined by histopathology and OSNA. Lymph nodes were divided into four representative blocks by a sterile, single use, special cutting device in the same way as in the clinical protocol study performed by Tsujimoto et al. Two blocks were used for histopathology and immunohistochemistry, 2 for OSNA.
  
  
  RESULTS
  Positive results of histopathology and OSNA were revealed in 4 patients. The outcomes of OSNA and histopathology were corresponding in 3 patients. Positive histopathology results of 2 lymph nodes from 2 patients were confirmed by OSNA. In 1 patient there were only negative results of both examinations. One-step nucleic acid amplification failed to detect metastasis in 1 lymph node in 2 patients although it did not change the TNM status in these patients. There were no false positive results in the OSNA test.
  
  
  CONCLUSIONS
  One-step nucleic acid amplification may be an alternative method to histopathology in detecting nodal involvement in MTC. Further studies should evaluate the sensitivity and specificity of OSNA and the impact on staging in MTC.
authors: Department of General and Oncological Surgery, University Hospital and Education Centre of Medical University of Lodz, Lodz, Poland.
authors: Krzysztof
authors: K
authors: Kaczka
authors: Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University of Lodz, Lodz, Poland.
authors: Wojciech
authors: W
authors: Fendler
authors: Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University of Lodz, Lodz, Poland.
authors: Maciej
authors: M
authors: Borowiec
authors: Department of Pediatrics, Oncology, Hematology and Diabetology, Medical University of Lodz, Lodz, Poland.
authors: Wojciech
authors: W
authors: Młynarski
authors: Department of General and Oncological Surgery, University Hospital and Education Centre of Medical University of Lodz, Lodz, Poland.
authors: Katarzyna
authors: K
authors: Paduszynska
authors: Department of General and Oncological Surgery, University Hospital and Education Centre of Medical University of Lodz, Lodz, Poland.
authors: Anna
authors: A
authors: Grzegory
authors: Department of General and Oncological Surgery, University Hospital and Education Centre of Medical University of Lodz, Lodz, Poland.
authors: Lech
authors: L
authors: Pomorski
keywords: histopathology; lymph nodes; medullary thyroid cancer; one-step nucleic acid amplification