Detection of STRN-ALK fusion in thyroid nodules with indeterminate cytopathology facilitates papillary thyroid cancer diagnosis

Diagn Cytopathol. 2021 Apr;49(4):E146-E151. doi: 10.1002/dc.24647. Epub 2020 Oct 21.

Abstract

Thyroid cancer is the most common endocrine malignancy. Approximately 70% of cases of papillary thyroid carcinoma and 50% of poorly differentiated and anaplastic thyroid carcinoma harbor well-characterized driver mutations and chromosomal rearrangements that drive tumorigenesis. Molecular profiling has been helpful in identifying and informing follow-up strategies in tumors with more aggressive trajectories. Here, we report a case of papillary thyroid cancer (PTC) discovered in a patient with thyroid nodules with relatively benign ultrasound and fine needle aspiration (FNA) findings. Molecular testing in this patient identified a rare STRN-ALK fusion in two thyroid nodules with indeterminate and/or benign cytology. This led to the patient undergoing a thyroid lobectomy and a subsequent confirmation of papillary thyroid carcinoma upon resection. The report highlights the role of comprehensive molecular testing in thyroid lesions of indeterminate cytology.

Keywords: STRN-ALK fusion; fine needle aspiration cytology; molecular profiling; papillary thyroid carcinoma.

Publication types

  • Case Reports

MeSH terms

  • Adult
  • Anaplastic Lymphoma Kinase / genetics*
  • Calmodulin-Binding Proteins / genetics*
  • Endoscopic Ultrasound-Guided Fine Needle Aspiration
  • Female
  • Genetic Testing
  • Humans
  • Membrane Proteins / genetics*
  • Nerve Tissue Proteins / genetics*
  • Oncogene Proteins, Fusion / genetics*
  • Thyroid Cancer, Papillary / diagnosis*
  • Thyroid Cancer, Papillary / genetics
  • Thyroid Cancer, Papillary / pathology
  • Thyroid Nodule / diagnosis*
  • Thyroid Nodule / genetics
  • Thyroid Nodule / pathology

Substances

  • Calmodulin-Binding Proteins
  • Membrane Proteins
  • Nerve Tissue Proteins
  • Oncogene Proteins, Fusion
  • STRN protein, human
  • ALK protein, human
  • Anaplastic Lymphoma Kinase