Tumor-to-tumor metastases to follicular variant of papillary thyroid carcinoma: histologic, immunohistochemical, and molecular studies of two unusual cases

Endocr Pathol. Winter 2009;20(4):235-42. doi: 10.1007/s12022-009-9087-x.

Abstract

Tumor-to-tumor metastasis in thyroid neoplasms is exceedingly uncommon. Two unusual cases of breast carcinoma and renal cell carcinoma metastatic to follicular variant papillary carcinoma are reported. On histologic sections, the donor tumor cells infiltrated the substance of the recipient tumor and the angiolymphatic channels, but the bulk of metastatic tumor was confined within the thyroid carcinoma. Immunohistochemical stains as well as molecular studies confirmed the origin of both donor tumors, as well as the diagnosis of follicular variant of papillary carcinoma in the recipient tumors. Distinguishing between two such tumor populations may be difficult when the donor tumor cells morphologically resemble primary neoplasms of the recipient organ. A history of previous malignancy and ancillary studies can be helpful in making this distinction and rendering the correct diagnosis. A brief review of literature and discussion of tumor-to-tumor metastasis in thyroid neoplasms is also presented.

Publication types

  • Case Reports

MeSH terms

  • Apoptosis Regulatory Proteins
  • Biomarkers / analysis
  • Biomarkers, Tumor / analysis
  • Breast Neoplasms / pathology
  • Carcinoma, Lobular / pathology
  • Carcinoma, Lobular / secondary
  • Carcinoma, Papillary, Follicular / pathology*
  • Carcinoma, Renal Cell / pathology
  • Carcinoma, Renal Cell / secondary
  • DNA-Binding Proteins / analysis
  • Female
  • Galectin 3 / analysis
  • Humans
  • Immunohistochemistry
  • Keratins / analysis
  • Kidney Neoplasms / pathology
  • Loss of Heterozygosity
  • Male
  • Microsatellite Repeats / genetics
  • Middle Aged
  • Neoplasm Metastasis / pathology*
  • Neoplasms, Second Primary / pathology*
  • Neprilysin / analysis
  • Nuclear Proteins / analysis
  • Thyroglobulin / analysis
  • Thyroid Neoplasms / pathology*
  • Thyroid Neoplasms / secondary*
  • Trans-Activators
  • Transcription Factors / analysis
  • Vimentin / analysis

Substances

  • Apoptosis Regulatory Proteins
  • Biomarkers
  • Biomarkers, Tumor
  • CAM 5.2 antigen
  • CITED1 protein, human
  • DNA-Binding Proteins
  • Galectin 3
  • HBME-1 antigen
  • Nuclear Proteins
  • TTF1 protein, human
  • Trans-Activators
  • Transcription Factors
  • Vimentin
  • Keratins
  • Thyroglobulin
  • Neprilysin