Establishing the First Diagnosis of Follicular Thyroid Carcinoma from the Femoral Metastatic Site in an 84-year-old Woman

Yunguang Liu, Frank Chen


Follicular thyroid carcinoma (FTC) commonly presents as a solitary thyroid nodule, which is diagnosed by thorough examination of thyroidectomy/lobectomy specimen for capsular and vascular invasions.  First diagnosis of FTC from femoral metastasis is very rare.  Here, we report such a case in an 84-year-old woman who presented with increasing pain in her left thigh.  A bone scan revealed multiple lesions in the bones including left femur.  Four years ago, the patient suffered right humeral pathological fracture.  The humeral lesion was positive for TTF-1 and was interpreted as “metastatic non-small cell carcinoma consistent with lung primary”.  However, subsequent bronchial washing and lung biopsy were negative for malignancy.  Biopsy of left femoral lesion showed solid nests of cells with round to oval nuclei and abundant eosionophilic/granular cytoplasm.  The nuclei of tumor cells contain one or more nucleoli and granular/vesicular chromatin.  No typical nuclear morphology of papillary thyroid carcinoma (PTC) was noted.  The tumor cells are positive for thyroglobulin and TTF-1, consistent with metastatic tumor from thyroid primary.  Immunostains of HBME-1 and CK19 only mark scattered tumor cells, which do not support the differential diagnosis of metastatic PTC.  CD56 and CK7 stains are both positive.  Upon further communication, patient's remote history of “thyroid follicular adenoma”, status post right lobectomy was obtained.  The femoral lesion was negative for BRAF mutation.  In conclusion, based on the overall morphological and immunohistochemical features as well as patient’s history, the final diagnosis of metastatic FTC was made.  We would like to raise the awareness that metastatic FTC should be included in the differential diagnoses for tumors metastasized to bone to avoid misdiagnosis.


Follicular thyroid carcinoma, metastasis, bone, diagnosis

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Pacini F, Schlumberger M, Dralle H, et al. European consensus for the management of patients with differentiated thyroid carcinoma of the follicular epithelium. Eur J Endocrinol. 2006;154(6):787–803.

Akdemir I, Erol FS, Akpolat N, Ozveren MF, Akfirat M, Yahsi S. Skull metastasis from thyroid follicular carcinoma with difficult diagnosis of the primary lesion. Neurol Med Chir (Tokyo). 2005;45(4):205–208.

Rahman GA, Abdulkadir Y, Olatoke SA, Yusuf IF, Braimoh T. Unusual cutaneous metastatic follicular thyroid carcinoma. J Surg Tech Case Rep. 2010;2(1):35-38.

Tahamtan M, Mokhtari M, Pakbaz S, Tahamtan M. Occult Follicular Thyroid Carcinoma Presenting as a Frontal Bone Metastasis: A Case Report. Case Report Med. 2012;2012:678935.

Mazzaferi E. Thyroid carcinoma: papillary and follicular. In Endocrine Tumors. Eds E Mazzaferi & N Saaman. Cambridge, MA: Blackwell Scientific. 1993:278–333.

Davies L, Welch HG. Increasing incidence of thyroid cancer in the United States:1973–2002. JAMA. 2006;295(18):2164–2167.

Coleman RE, Rubens RD. The clinical course of bone metastases from breast cancer. Br J Cancer. 1987;55(1):61-66.

Disibio G, French SW. Metastatic patterns of cancers: results from a large autopsy study. Arch Pathol Lab Med. 2008;132(6):931-939.

Comperat E, Zhang F, Perrotin C, et al. Variable sensitivity and specificity of TTF1 antibodies in lung metastatic adenocarcinoma of colorectal origin. Mod Pathol. 2005;18(10):1371-1376.

Nakamura N, Miyagi E, Murata S, et al. Expression of thyroid transcription factor-1 in normal and neoplastic lung tissues. Mod Pathol. 2002;15(10):1058–1067.

Ordonez NG. Value of thyroid transcription factor-1 immunostaining in distinguishing small cell lung carcinomas from other small cell carcinomas. Am J Surg Pathol. 2000;24(9):1217-1223.

Katoh R, Miyagi E, Nakamura N, et al. Expression of thyroid transcription factor-1 (TTF1) in human C cells and medullary thyroid carcinomas. Hum Pathol. 2000;31(3):386-393.

Pan CC, Chen PC, Tsay SH, et al. Cytoplasmic immunoreactivity for thyroid transcription factor-1 in hepatocellular carcinoma: a comparative immunohistochemical analysis of four commercial antibodies using a tissue array technique. Am J Clin Pathol. 2004;121(3):343-349.

Cheung CC, Ezzat S, Freeman JL, Rosen IB, Asa SL. Immunohistochemical diagnosis of papillary thyroid carcinoma. Mod Pathol. 2001;14(4):338-342.

Lam KY, Lui MC, Lo CY. Cytokeratin expression profiles in thyroid carcinomas. Eur J Surg Oncol. 2001;27(7):631-635.

Scognamiglio T, Hyjek E, Kao J, Chen YT. Diagnostic usefulness of HBME1, galectin-3, CK19, and CITED1 and evaluation of their expression in encapsulated lesions with questionable features of papillary thyroid carcinoma. Am J Clin Pathol. 2006;126(5):700-708.

de Matos PS, Ferreira AP, de Oliveira Facuri F, Assumpção LV, Metze K, Ward LS. Usefulness of HBME-1, cytokeratin 19 and galectin-3 immunostaining in the diagnosis of thyroid malignancy. Histopathology. 2005;47(4):391-401.

Demellawy DE, Nasr A, Alowami S. Application of CD56, P63 and CK19 immunohistochemistry in the diagnosis of papillary carcinoma of the thyroid. Diagn Pathol. 2008;3:5.

Lee JH, Lee ES, Kim YS. Clinicopathologic significance of BRAF V600E mutation in papillary carcinomas of the thyroid: A meta-analysis. Cancer 2007;110(1):38–46.


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