Incidental discovery of a Hodgkin lymphoma synchronous to a papillary thyroid carcinoma

Papillary thyroid carcinoma is the most common type of thyroid cancer and accounts for almost 89.4% of all thyroid carcinomas. Hodgkin lymphoma is a heterogeneous group of neoplasms and represents 10% of lymphomas. These two cancers do not share the same risk factors. Some studies have reported the association of thyroid papillary carcinoma with lymphomas, mainly Hodgkin's lymphoma, treated with radiotherapy. However, to our knowledge less than 10 cases have illustrated synchronous papillary thyroid carcinoma and Hodgkin lymphoma with no history of radiotherapy. We present the case of a 49‐year‐old female patient, with no history of past exposure to radiation, who was incidentally diagnosed with Hodgkin lymphoma during the work up for papillary thyroid carcinoma. Our patient had total thyroïdectomy with cervical lymphadenectomy. The histopathologic examination concluded to a papillary thyroid carcinoma of classical variant. And the lymph node dissection enabled us to diagnose not only papillary thyroid carcinoma's lymph node metastasis, but also Hodgkin Lymphoma. This discovery of the Hodgkin lymphoma was totally incidental. The discovery of synchronous tumors in patients with papillary thyroid carcinoma has been reported in the literature. However, the diagnosis of Hodgkin through lymph node dissection for papillary thyroid carcinoma is extremely rare. This underlines the singularity and the importance of our case. The synchronous papillary thyroid carcinoma and Hodgkin lymphoma is a rare condition, which may pose significant diagnostic and treatment dilemmas. To date, there is no standardized approach due to lack of experience. The molecular mechanisms of this link are poorly understood and yet remain to be elucidated.

Cystic cervical lymph nodes of papillary thyroid carcinoma, tuberculosis and human papillomavirus positive oropharyngeal squamous cell carcinoma: Comparative CT analysis for their differentiation

PURPOSE

Cervical lymph nodes with cystic changes are an important finding seen with several pathologies including papillary thyroid carcinoma (PTC), tuberculosis (TB) and HPV-positive oropharyngeal squamous cell carcinoma (HPV + OPSCC). In the absence of known primary tumor or conclusive medical history, differentiating among these nodes is difficult. We compared the pathologic nodes of PTC, TB and HPV + OPSCC to identify imaging features useful for their differentiation.

MATERIALS AND METHODS

Fifty-five PTC, 58 TB and 51 HPV + OPSCC nodes were selected based on surgical pathology records and suspicious morphological features. These nodes were compared for morphological features: long axis length, nodal shape, nodal location, presence of cystic change, area of cystic change:area of entire node ratio, Hounsfield unit of the cystic component, degree of enhancement, enhancement pattern, presence of calcification, presence of perinodal infiltration, and presence of surrounding inflammatory changes.

RESULTS

PTC nodes formed calcifications more frequently and demonstrated greater enhancement (P < 0.01). TB nodes were characterized by their irregular shape (P < 0.05), irregular enhancement surrounding the cystic change (P < 0.01), greater frequencies of perinodal infiltration (P < 0.01) and surrounding inflammatory changes (P < 0.01). While no unique features were seen with HPV+OPSCC, they were characterized by the absence of those features that distinguished the other groups: these nodes tended to have smooth, circumscribed margins with no hyperenhancement, calcifications or inflammatory changes. PTC and TB nodes were more frequently identified in the lower neck, while HPV+OPSCC nodes were localized to the upper neck (P < 0.01).

CONCLUSIONS

PTC, TB and HPV + OPSCC lymph nodes can be differentiated based on their morphologies and locations.

Upregulation of long noncoding RNA LOC100507661 promotes tumor aggressiveness in thyroid cancer

Recent advances in next-generation sequencing have revealed a variety of long noncoding RNAs (lncRNAs). However, studies of lncRNAs are at a very early stage, our knowledge of the biological functions and clinical implications remains limited. To investigate the roles of lncRNAs in thyroid cancers, we verified 56 lncRNAs identified as potential cancer-promoting genes in a previous study that analyzed 2394 tumor SNP arrays from 12 types of cancer. Based on verified sequence information in NCBI and Ensembl, we ultimately selected three candidate lncRNAs for detailed analysis. One of the candidates, LOC100507661, was strongly upregulated in thyroid cancer tissues relative to paired contralateral normal tissue. LOC100507661 was easily detectable in papillary and anaplastic thyroid cancer cell lines such as TPC1, BCPAP, C643, and 8505C, but not in the follicular thyroid cancer cell line FTC133. Stable overexpression of LOC100507661 promoted cell proliferation, migration, and invasion of thyroid cancer cells. Lymph node metastasis and BRAF V600E mutations were more frequent in papillary thyroid cancers with high LOC100507661 expression. Our data demonstrate that LOC100507661 expression is elevated in human thyroid cancer and may play a critical role in thyroid carcinogenesis.