There are limited data on the role of neck ultrasound (US) in the surveillance of patients with follicular thyroid cancer (FTC). Here, we analyze the likelihood of US to find structural disease in patients with FTC and evaluate if initial American Thyroid Association (ATA) risk stratification and the response to therapy categories [the latter based on thyroglobulin (Tg) levels] modify that likelihood. We conducted a retrospective cohort study of 32 patients with FTC in our institution. We included all patients with well-differentiated FTC who underwent total thyroidectomy and radioactive iodine (RAI) treatment without neck structural disease at the time of RAI and with Tg and US at least 6 months after RAI. After a median follow-up of 4.3 years, two patients (6.3%) had structural disease by US. None of the 18 patients with initial ATA low-risk disease had structural disease by US in contrast to higher, but not significant, frequency of 18.2% (2/11) in patients with initial ATA high-risk disease (p = 0.14). Based on Tg levels, 24/32 patients had excellent response to therapy and 8/32 had biochemical incomplete/indeterminate response. None of the patients with excellent response had structural disease by US versus 2/8 (25%) patients with biochemical incomplete/indeterminate response all of whom had other sites of structural disease (p = 0.054). Our findings suggest that neck US in FTC is unlikely to find structural disease with initial low-risk ATA or excellent response to therapy but can detect structural disease in some patients with initial ATA high-risk or incomplete/indeterminate responses to therapy.

Hürthle cell thyroid cancer (HCTC) is a less common form of differentiated thyroid cancer. It rarely metastasizes to the liver, and when it does, the metastasis is almost never isolated. Here we report a 62-year-old male with widely invasive Hürthle cell thyroid cancer, who underwent total thyroidectomy and received adjuvant treatment with I-131 with posttreatment scan showing no evidence of metastatic disease. His thyroglobulin however continued to rise after that and eventually an isolated liver metastasis was identified. He underwent laparoscopic microwave ablation of the liver metastasis, with dramatic decline in thyroglobulin and no structural disease identified to date. This case highlights the rare occurrence of isolated liver metastasis from HCTC and also illustrates the utility of thermoablation as an alternative to surgical resection in the treatment of small isolated liver metastases from HCTC.

Primary intracranial and sellar squamous cell carcinoma is an extremely rare entity, usually caused by malignant transformation of epidermoid cysts, or very rarely other non-malignant epithelial cysts. Malignant transformation of a Rathke’s cleft cyst has never been described. We present a 49-year-old male patient who presented with a 3-month history of progressive frontotemporal headaches. Imaging revealed a 1.2 cm cystic pituitary mass consistent with a hemorrhagic Rathke’s cleft cyst. The patient underwent trans-sphenoidal resection of the pituitary cyst, and pathologic analysis revealed a squamous cell carcinoma lining a Rathke’s cleft cyst. Extensive imaging and otorhinolaryngologic evaluation revealed no primary source for metastasis. We feel this represents the first case of a patient with a pituitary lesion in which presentation and MRI imaging were consistent with Rathke’s cleft cyst, yet histology revealed squamous cell carcinoma in situ.

No abstract

Objective: The PIK3CA (p.H1047R) mutation has only been identified in advanced poorly differentiated and anaplastic thyroid cancer in the past. We are describing the first reported case of this PIK3CA mutation in a benign thyroid nodule of a patient with multiple endocrine neoplasia type 1 (MEN-1) syndrome, which raises caution to the aggressive treatment approach usually taken when this mutation is identified. Methods: A 49-year-old female was found to have primary hyperparathyroidism with multigland disease and tested positive for MEN-1 syndrome. Further evaluation also identified a thyroid nodule, which had indeterminate cytology on fine-needle aspiration biopsy. The ThyroSeq 2.0 assay identified a PIK3CA mutation (p.H1047R, c.3140A>G), which led to a total thyroidectomy. Pathology showed a benign thyroid nodule. Results: To our knowledge, this is the first case reporting a PIK3CA (p.H1047R) mutation in a benign thyroid nodule, particularly in a patient with MEN-1 syndrome. Conclusion: Clinicians should be aware that this mutation can be identified in benign thyroid nodules and that aggressive management is not always warranted. Further research is needed to improve our understanding of thyroid cancer etiology and improve our ability to identify with high accuracy malignant and benign thyroid nodules when we are faced with indeterminate thyroid nodule cytology. (AACE Clinical Case Rep. 2018;4:e320-e323) Abbreviations: FNA = fine-needle aspiration; MEN-1 = multiple endocrine neoplasia 1; PHPT = primary hyperparathyroidism; PIK3CA = phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha