Endocrine Abstracts

Introduction

While cervical lymph nodes are the region where head and neck malignancies frequently metastasize, prostate carcinoma rarely metastasizes to this area. Here, we will present a case with papillary thyroid microcarcinoma whose pathological lymph node cytology in the cervical region was found to be prostate carcinoma metastasis.

Case

Since thyroid fine needle aspiration cytology (FNAC) results were non-diagnostic 3 times, an 64-year old male patient underwent bilateral total thyroidectomy. His pathological examination was compatible with papillary microcarcinoma, and was given 100 mci radioactive iodine (RAI) treatment. While post-ablation whole body scan (WBS) revealed the activity involvement compatible with residual tissue in the right lobe region, the diagnostic WBS was found to be normal (TSH, Tg and Anti Tg values are shown in Table 1). In PET-CT, pathological increased activity uptake was detected in the bilateral level IV lymph node area. Neck ultrasonography showed a lymph node with pathological appearance and 8.5 × 8.7 × 11 mm in size at left level IV. Cytological examination of this lymph node was compatible with carcinoma metastasis. Also, another pathological looking lymph node on the left level IV with 7.7 × 9.4 × 10.8 mm in size was found to be compatible with malignant cytology, carcinoma metastasis (Table 1). An immunohistochemical study of the prostate and thyroid origin (PSA, TTF1) has been conducted in cytology, but a definitive clue for the origin of the tumor has not been obtained. Thereupon, the FNAC was repeated from the level IV lymph node (8.5 × 8.7 × 11 mm) of the patient and non-diagnostic cytology was found, afterall the cell block was applied. Finally, left level IV lymph node cytology was reported to be compatible with prostate adenocarcinoma metastasis.

TSH; thyroid stimulating hormone, Tg; thyroglobulin, Anti-Tg; anti- thyroglobulin, WBS; whole body scan, RAI; radioactive iodine

Conclusion

Metastatic prostate adenocarcinoma (PAC) to cervical lymph nodes is rare. If the history is unknown, cases may be misdiagnosed as metastases from cervical neoplasms. Findings showing metastatic PAC to the cervical lymph nodes in FNAC are; the involvement of left-sided cervical lymph nodes and cellular smears consisting of flat layers with granular cytoplasm and uniform polygonal cells arranged in the acini, fuzzy cell borders, and round-oval nuclei with prominent nucleoli.