Colon Cancer Metastasis Within a NIFTP: A Case Report and Review of the Literature

Outcomes of thyroidectomy for secondary thyroid malignancies, a single center experience

BACKGROUND

Metastasis of primary malignancies of other organs to the thyroid gland is a rare condition that may pose a diagnostic challenge. In this study, we aimed to report the clinicopathologic features and outcomes of patients treated for secondary thyroid malignancies in our center.

MATERIALS AND METHODS

The results of patients who underwent thyroidectomy in our clinic between 2015 and 2023 were evaluated retrospectively. Four patients who met the inclusion criteria were evaluated.

RESULTS

The primary tumor was renal cell carcinoma in 2 patients and squamous cell carcinoma of the lung in 2 patients. Median age was 64 years (min:59-max:69). The median nodule diameter was 2.85 cm. Extrathyroidal spread was present in 1 patient with renal cell carcinoma metastasis. The other patient with renal cell carcinoma metastasis had lymphatic invasion. Vascular invasion was detected in 1 patient with renal cell carcinoma metastasis and 1 patient with squamous cell carcinoma of the lung metastasis. Surgical margin positivity was present in 1 patient in each group. The median overall survival time was 27 (min:10-max:44) months in the renal cell carcinoma group and 11 (min:6-max:16) months in the squamous cell carcinoma group. After the diagnosis of primary renal cell carcinoma, one patient metastasized to thyroid tissue 43.00 and one patient 94.00 months later. In the squamous cell carcinoma group, one patient showed metastasis to thyroid tissue 6.00 months after the primary diagnosis, while the other patient was first diagnosed with metastatic tissue.

CONCLUSIONS

Metastasis to the thyroid gland is a rare phenomenon with an incidence of 0.22% in all thyroid malignancies. It may occur before the detection of the primary tumor or during the follow-up of the primary malignancy. Although the overall prognosis is poor, it can be treated surgically.

Metastases to the Thyroid Gland: What Can We Do?

Metastases to the thyroid gland arise from other malignant tumors such as renal cell carcinoma, colorectal cancer, lung cancer, and breast cancer. In clinical practice, the incidence is low, and the symptoms are not specific, so it is often missed and misdiagnosed. It is finally diagnosed via the comprehensive application of many diagnostic methods, such as ultrasound, fine-needle aspiration biopsy, and immunohistochemistry analysis. Surgery-based comprehensive treatment is often adopted, but because it is usually in the late stage of the primary tumor, the prognosis is poor. In order to better understand the related characteristics of thyroid metastatic cancer and then improve the clinical diagnosis and treatment and the prognosis of patients, in this paper, we systematically summarize the research status of thyroid metastatic cancer.

Pitfalls in Challenging Thyroid Tumors: Emphasis on Differential Diagnosis and Ancillary Biomarkers

Thyroid pathology encompasses a heterogenous group of clinicopathological entities including rare and diagnostically challenging neoplasms. The review is focused on morphological, immunohistochemical, and molecular features of rare thyroid neoplasms that can pose diagnostic problems. The tumors are organized based on growth patterns including thyroid neoplasms with predominantly papillary, follicular, solid, and spindle cell growth pattern, as well as neoplasms with distinct cytological characteristics. A special section is also dedicated to rare thyroid tumors with peculiar patterns including thyroid carcinoma with Ewing family tumor elements and intrathyroidal thymic-related neoplasms.