Primary squamous cell carcinoma of the thyroid on FDG PET/CT

Primary thyroid squamous cell carcinoma diagnosed with 18F-FDG PET/CT: a case report

Primary thyroid squamous cell carcinoma is extremely rare. We report a case of primary thyroid squamous cell carcinoma diagnosed using 18F-FDG PET/CT. The patient presented with left axillary lymphadenopathy as the initial symptom. Fine-needle aspiration of the axillary lymph nodes indicated metastatic squamous cell carcinoma. To identify the primary tumor, the patient underwent an 18F-FDG PET/CT scan, which revealed a mass in the thyroid and multiple enlarged lymph nodes with abnormal FDG uptake. Pathological examination of the axillary lymph nodes and thyroid biopsy confirmed the diagnosis of primary thyroid squamous cell carcinoma with lymph node metastasis.

Clinical analysis of 13 cases of primary squamous-cell thyroid carcinoma

Objective

To analyze the clinical features, ultrasonographic manifestations, pathological features, treatment and prognosis of primary thyroid squamous cell carcinoma (PSCTC) and summarize the experience in diagnosis and treatment of this condition.

Methods

A retrospective analysis was conducted on patients who were admitted to Zhejiang Cancer Hospital from 2007 to 2021 due to thyroid nodules or thyroid malignant tumors that were ultimately confirmed by postoperative pathology as primary thyroid squamous cell carcinoma. We summarize the general situation, clinical information, laboratory examination, ultrasonic image characteristics, pathological examination, clinical treatment and prognosis of the patients.

Results

PSCTC is most often seen in older men and progresses rapidly. In laboratory tests, some patients had elevated levels of tumor markers (CA199, squamous cell carcinoma antigen level), thyroglobulin levels and tumor-related substances, but all these indicators lacked specificity. The ultrasound features of PSCTC are mainly hypoechoic, hard, substantial nodules with gross borders and a grade 1-2 blood flow signal, sometimes with signs of necrosis and calcification. In terms of treatment, PSCTC is mainly surgically resected, though some patients in this study underwent iodine-131 radiation therapy, local radiotherapy, and chemotherapy with unclear results. None of the patients survived for very long after treatment, but the prognosis of patients with highly differentiated squamous carcinoma was significantly better than that of patients with poorly differentiated squamous carcinoma. Papillary thyroid carcinoma may be one of the causes of PSCTC.

Conclusion

PSCTC is a malignant tumor with high malignancy and rapid clinical progression. Treatment options are mainly based on surgical resection and can be supplemented with radiotherapy and chemotherapy, but there is still a lack of a standardized treatment management system, and more cases and reports are needed to accumulate data.

Analysis of primary and secondary squamous cell carcinoma of the thyroid gland: a retrospective study

Background

Squamous cell carcinoma of the thyroid (SCCT) is a kind of rare malignant disease. This study aimed to analyse the clinical characteristics of patients with primary SCCT (PSCCT) and secondary SCCT (SSCCT).

Methods

The medical records of seventeen patients with PSCCT and six patients with SSCCT were reviewed. Clinical symptoms, ultrasound, and pathological characteristics were compared between the two groups.

Results

The mean age of diagnosis was approximately 56 years old in each group. The most common chief complaint of the patients was neck mass in both groups. The percentage of patients with cough (P=0.008) or weight loss (P=0.021) was higher in the SSCCT group than the PSCCT group. The mean size of the tumor in the PSCCT group was larger than that in the SSCCT group (3.382±2.011 vs. 1.950±0.794 cm, P=0.024). Papillary thyroid carcinoma (PTC) could be combined with or recur as PSCCT. Kaplan-Meier analysis indicated that the mean survival times after diagnosis were 17.053 months in the PSCCT patients and 13.500 months in the SSCCT patients. Multivariate survival analysis using a Cox regression model demonstrated that predictors of overall survival (OS) in PSCCT patients included age (P=0.020), enlarged cervical lymph node (P=0.017), radical operation (P=4.82×10^-3), and PTC (P=0.03).

Conclusions

SCCT is aggressive, with neck mass being the most common chief complaint. There were several different characteristics between PSCCT and SSCCT. PTC could be combined with or recur as PSCCT. Age, enlarged cervical lymph node, radical operation, and PTC were the predictors of OS in PSCCT patients.

Treatment optimization and prognostic considerations for primary squamous cell carcinoma of the thyroid

Background

Primary squamous cell carcinoma of the thyroid (PSCCT) is a rare aggressive malignancy that usually presents in an advanced stage and has a poor prognosis. Our study aimed to investigate the clinical characteristics, treatment, and prognosis of PSCCT.

Methods

We retrospectively reviewed the medical information of patients with PSCCT diagnosed from January 2006 to May 2018 at Xiangya Hospital. Survival analysis was conducted using the Kaplan-Meier method, and Log-Rank tests were performed for statistical testing.

Results

We identified 12 patients with PSCCT (nine males and three females), accounting for only 0.19% of all thyroid cancer diagnosed during this time period. The median age of these patients was 59.5 years old and their symptoms included neck masses (n=5), hoarseness (n=2), dyspnea (n=1), dysphagia (n=1) and neck pain (n=1). Four patients were in stage IVA, five were stage IVB, and three patients were stage IVC. Six patients underwent comprehensive treatment (surgery + radiotherapy or surgery + radiotherapy + chemotherapy) and the remaining patients received radiotherapy and/or chemotherapy. The 6-month survival rate was 66.7%, compared to a 1-year survival rate of 25.0%, with a median overall survival time was 10.5 months. Kaplan-Meier analysis showed that the comprehensive treatment was superior to radiotherapy and/or chemotherapy (P=0.003).

Conclusions

PSCCT is a rare type of thyroid cancer that is highly invasive and has a poor prognosis. We show that a comprehensive treatment plan can significantly improve patient survival.

Primary squamous cell carcinoma of the thyroid. Initial assessment and follow-up using 18F-FDG PET/CT

Squamous cell carcinoma of thyroid is an uncommon, very aggressive neoplasm, having a poor prognosis and poor response to chemotherapy and radiotherapy. Surgery is the initial treatment of choice, although it often presents as a widespread disease at the time of diagnosis, usually with cervical swelling that causes most of the symptoms due to local infiltration or metastasis. Local infiltration from adjacent tumour and metastatic disease needs to be excluded from other primary epidermoid carcinomas, in order to make a correct diagnosis. This also requires the typical cytokeratin pattern seen in histological studies. The case is presented of a 53 year-old man with a medical history of hepatocarcinoma, with a cervical hypermetabolic lesion detected in an ¹⁸F-FDG PET/CT performed to exclude widespread disease. The follow-up of this lesion with this technique and its usefulness is also described.