Primary low-grade salivary gland-type intraductal carcinoma of the lung with CCDC6::RET fusion: Case presentation and literature review

Am J Clin Pathol. 2025 Jun 3;163(6):877-882. doi: 10.1093/ajcp/aqaf014.

Abstract

Objectives: Salivary gland-type intraductal carcinoma (IC) is a rare type of low-grade salivary gland neoplasm. Given that the clinical and imaging features of primary lung IC are nonspecific, the diagnosis requires pathologic analysis.

Methods: We report a 63-year-old woman with primary low-grade salivary gland-type IC of the lung, characterized by an origin from the bronchus submucosa, an intraductal or intracavity growth of ductal epithelium, an absence of interstitial infiltration, and harboring an RET::CCDC6 fusion.

Results: Through case presentation and a literature review, we discuss the differential diagnosis and clinical management of salivary gland-type IC of the lung.

Conclusions: Molecular testing is not necessary for histologic subtyping but can aid in the differential diagnosis of IC.

Keywords: CCDC6::RET fusion; diagnosis; lung neoplasms; pathology; primary lung intraductal carcinoma.

Publication types

  • Case Reports
  • Review

MeSH terms

  • Carcinoma, Intraductal, Noninfiltrating* / diagnosis
  • Carcinoma, Intraductal, Noninfiltrating* / genetics
  • Carcinoma, Intraductal, Noninfiltrating* / pathology
  • Diagnosis, Differential
  • Female
  • Humans
  • Lung Neoplasms* / diagnosis
  • Lung Neoplasms* / genetics
  • Lung Neoplasms* / pathology
  • Middle Aged
  • Oncogene Proteins, Fusion / genetics
  • Proto-Oncogene Proteins c-ret* / genetics

Substances

  • Proto-Oncogene Proteins c-ret
  • RET protein, human
  • Oncogene Proteins, Fusion