Phyllodes Tumor Metastatic to Thyroid HürthleCell Adenoma

Non-papillary thyroid carcinoma diagnoses in The Bethesda System for Reporting Thyroid Cytopathology categories V and VI: An institutional experience

BACKGROUND

The non-papillary thyroid carcinoma (PTC) subgroups of The Bethesda System for Reporting Thyroid Cytopathology (TBSRTC) categories V (Suspicious for malignancy) and VI (Malignant) are rare, and specific tumor typing is difficult. We aimed to analyze histologic outcomes and to investigate the points of caution.

METHODS

We reviewed the electronic database and identified 12,215 cases of thyroid fine-needle aspiration cytology between 2013 and 2022. In total, 2783 patients were diagnosed with TBSRTC V or VI. Of these, 51 patients with non-PTC diagnosis were identified. Histological outcomes were analyzed with the cytologic findings.

RESULTS

The subgroups of non-PTC diagnoses in TBSRTC category V or VI consisted of medullary thyroid carcinoma (MTC) (13/51, 25.5 %), anaplastic thyroid carcinoma (3/51, 5.9 %), lymphoma (2/51, 3.9 %), metastatic tumor (4/51, 7.8 %), and malignant, not otherwise specified (NOS) (29/51, 56.9 %). The concordance rate of the histological outcomes was 30 % (12/40), predominantly comprising MTC cases. The obscuring factors for specific tumor typing in the suspicious for malignancy/malignant NOS cytology diagnosis group was mixed pattern of well differentiated thyroid carcinoma and less differentiated carcinoma cells (9/24, 37.5 %), low cellularity (7/24, 29.2 %) and a history of non-thyroid organ malignancy (6/24, 25 %). The less differentiated carcinoma component in mixed pattern consisted of 2 poorly differentiated thyroid carcinomas, 2 anaplastic thyroid carcinomas, 4 high-grade PTCs and 1 high-grade MTC.

CONCLUSION

The high-grade feature of PTC or MTC cytology is a noteworthy obscuring factor in specific tumor typing of non-PTC cytology diagnosis.

Metastatic Disease to a Concurrent Thyroid Neoplasm: A Case Series and Review of the Literature

BACKGROUND

Metastatic disease to the thyroid gland is uncommon but well-described. Metastatic disease to a concurrent primary thyroid neoplasm is a rare phenomenon. We sought to study patients with metastasis to the thyroid with a focus on the histopathologic and clinical features in tumor-to-tumor metastasis.

METHODS

We identified a series of patients with metastatic disease to the thyroid, with or without a concurrent primary neoplasm, through a search of the files of the Department of Pathology. All relevant slides were retrieved and reviewed, including routine HE and immunohistochemical stains. We performed a detailed English language literature search (1962-2022) and review to identify tumor-to-tumor metastasis involving the thyroid.

RESULTS

We identified 14 patients with metastasis to the thyroid over a 22-year period. Four patients exhibited papillary thyroid carcinoma, with metastatic spread of a different malignancy seeding into the thyroid cancer. We describe the histopathologic diagnostic process and findings, clinical management, and the clinical course of tumor-to-tumor metastasis in greater detail for these 4 patients.

CONCLUSION

Tumor-to-tumor metastasis to the thyroid is a rare event with unique histopathologic features. Our findings suggest that the phenomenon of tumor-to-tumor metastasis serves to highlight broader mechanisms of metastatic disease in general. We provide the largest-to-date and comprehensive review of the literature to identify all previous reported instances of tumor-to-tumor metastasis involving the thyroid.

Clinicopathological and Molecular Features of Secondary Cancer (Metastasis) to the Thyroid and Advances in Management

Secondary tumours to the thyroid gland are uncommon and often incidentally discovered on imaging. Symptomatic patients often present with a neck mass. Collision tumours of secondary tumours and primary thyroid neoplasms do occur. Ultrasound-guided fine-needle aspiration, core-needle biopsy, and surgical resection with histological and immunohistochemical analysis are employed to confirm diagnosis as well as for applying molecular studies to identify candidates for targeted therapy. Biopsy at the metastatic site can identify mutations (such as EGFR, K-Ras, VHL) and translocations (such as EML4-ALK fusion) important in planning target therapies. Patients with advanced-stage primary cancers, widespread dissemination, or unknown primary origin often have a poor prognosis. Those with isolated metastasis to the thyroid have better survival outcomes and are more likely to undergo thyroid resection. Systemic therapies, such as chemotherapy and hormonal therapy, are often used as adjuvant treatment post-operatively or in patients with disseminated disease. New targeted therapies, such as tyrosine kinase inhibitors and immune checkpoint inhibitors, have shown success in reported cases. A tailored treatment plan based on primary tumour features, overall cancer burden, and co-morbidities is imperative. To conclude, secondary cancer to the thyroid is uncommon, and awareness of the updates on diagnosis and management is needed.

Rare case of metastatic liposarcoma to the thyroid gland and a review of the literature of metastatic sarcomas to the thyroid

BACKGROUND

Liposarcomas are the second most common type of soft tissue sarcomas. Typically, myxoid liposarcomas have a metastatic rate of 10%, usually involving the retroperitoneal space, abdomen, and spine. Metastasis to the thyroid is extremely rare.

DESIGN/METHOD

A 62-year-old male with a history of metastatic myxoid liposarcoma in his right thigh presented to our clinic for evaluation of a thyroid nodule incidentally identified on a CT scan. A subsequent FNA biopsy was suggestive of a metastatic liposarcoma.

RESULTS

The patient underwent a left thyroid lobectomy and final pathology confirmed a grade II/III metastatic myxoid liposarcoma that measured 3.3 cm. The patient tolerated the procedure well.

CONCLUSIONS

Our case highlights the role of a patient's medical history when evaluating thyroid nodules to optimize accurate diagnosis, as liposarcomas do not typically metastasize to the thyroid. We also provide an updated review of the literature on all cases of metastatic sarcomas to the thyroid.

Isolated thyroid metastasis from benign phyllodes tumour

We present a rare and interesting case of a 35-year-old woman who initially underwent an uneventful wide excision for a 13 cm left benign phyllodes tumour. She then noted a slowly growing left thyroid nodule 8 months postsurgery which on thyroidectomy 4 years later was shown to be a 6.9cm isolated thyroid metastasis from the phyllodes tumour. As this may be the first reported such case in the literature, implications on histological classification, predictive factors for disease progression, mechanisms of metastasis, and evaluation, management and surveillance of benign phyllodes tumours and thyroid nodule/s with a history of phyllodes tumour can thus be significantly impacted.

Prostate Cancer Metastasis to Thyroid Gland

Metastases to the thyroid gland are rarely encountered in clinical practice. They may originate from various primary sites, mainly kidney, lung, breast, esophagus and uterus. Prostate cancer is one of the most frequent malignancies in men. It generally has a favorable course, and autopsy series have shown occult prostate cancer in many subjects, especially in aged males. However, prostate cancer sometimes exhibits an aggressive behavior and cases with a poor prognosis have been reported. Occasional reports of metastasis from prostate cancer to the thyroid gland have been documented. We describe the case of a 73-year-old patient presenting with thyroid metastasis from long-standing prostate cancer.

Atypical Distant Metastasis of Breast Malignant Phyllodes Tumors: A Case Report and Literature Review

Malignant phyllodes tumors (MPT) are rare breast neoplasms. Preoperative diagnosis is often challenging due to the unspecific clinical, radiological, and histological characteristics of the tumor. Dissemination pathways are local with chest wall invasion, regional with lymph nodes metastasis, and distant, hematogenous, mostly to the lungs, bones, and brain. Distant metastasis (DM) can be synchronous or appear months to years after the diagnosis and initial management. The current report describes the case of a 57-year-old woman presenting with a giant/neglected MPT of the breast, with no DM at initial staging, treated by radical modified mastectomy. Motor disorders due to medullar compression by a paravertebral mass appeared at short follow-up, also treated surgically. The patient died from several DM of rapid evolution. To our knowledge, this is the only case described of MPT with metastases to soft tissue causing medullar compression. We present a literature review on unusual metastatic localizations of MPT.

An extraordinary case of mesenchymal chondrosarcoma metastasis in the thyroid

Secondary tumours of the thyroid gland account for 1.25 to 3 % in clinical series and reach 24 % in autopsy series. Chondrosarcoma is a rare malignant mesenchymal tumour of chondrogenic nature; the mesenchymal variant represents less than 3 % of all chondrosarcomas, being therefore extremely rare. A mesenchymal chondrosarcoma metastasis in the thyroid is exceptional; to our knowledge, only three previous cases of chondrosarcoma metastasis in the thyroid have been reported to date but none of such cases corresponded to a mesenchymal chondrosarcoma. We present the first of such a case in a 27-year-old woman with a 4-year history of mesenchymal chondrosarcoma of the sacrum that was treated by surgery and chemotherapy. At the present admission, head and neck computed tomography revealed a well-defined nodule in the thyroid gland. The diagnosis of metastasis from the mesenchymal chondrosarcoma was made in the right lobectomy specimen.

Chondrosarcoma metastasis in the thyroid gland: a case report

Introduction

Chondrosarcoma metastases in the thyroid gland are exceptional. To the best of our knowledge, only two cases have been previously reported in the literature. Here we report the third case.

Case presentation

We report the case of a 51-year-old Arab woman who presented in 2011 with a diaphyseal chondrosarcoma of her right tibia treated by surgery. In the last quarter of 2013, she presented a hard mass in her thyroid gland with dyspnea and a right laryngeal paresis. She underwent a debulking surgery with tracheostomy in order to prevent difficulty in respiration. The final pathology revealed the diagnosis of a chondrosarcoma metastasis within her thyroid gland. She died several days later.

Conclusions

Even if primary and metastatic chondrosarcomas of the thyroid gland are exceptional, they should be considered in the differential diagnosis of thyroid gland masses. The prognosis is poor but surgery may help preserve quality of life.

Phyllodes tumor metastasis to the tonsil with synchronous undifferentiated carcinoma

INTRODUCTION

Breast tumor metastasis to the tonsil is extremely rare.

PRESENTATION OF CASE

A 54-year-old woman underwent resection of a breast malignant phyllodes tumor and later presented with metastasis to the lung and the left tonsil. She underwent left lower lobectomy and resection of the left tonsillar tumor. She subsequently developed undifferentiated carcinoma of the right tonsil. She underwent resection of the right tonsillar tumor and chemotherapy was started. The central venous catheter became infected with methicillin-resistant Staphylococcus aureus. Finally, she died.

DISCUSSION

To the best of our knowledge, this is the first reported case of a phyllodes tumor metastasizing to the tonsil. Furthermore, morphological and immunohistochemical study revealed that the right tonsillar tumor was irrelevant to the phyllodes tumors.

CONCLUSION

We report a case of phyllodes tumor metastasis to the left tonsil which developed undifferentiated carcinoma in the other side of tonsil later. Breast tumor metastasis to the tonsil is rare but it should be considered as a possible diagnosis.

Metastatic carcinoma to the thyroid gland: a single institution 20-year experience and review of the literature

The thyroid gland is an uncommon site for metastatic disease but cases have been well-documented in the literature, particularly in autopsy series. A retrospective review of surgical pathology and autopsy pathology database for patients with metastatic carcinoma to the thyroid was performed at the University of Massachusetts Medical Center between January 1993 to January 2013. We identified a total of 10 patients with metastatic carcinoma to the thyroid; 6 were in surgical pathology specimens out of a total of 1,295 thyroid carcinoma (0.46 %) and 4 were diagnosed at autopsy out of a total of 2,117 (0.19 %) autopsy cases during this period. Cases with direct extension of the tumor into the thyroid from local primary sites such as larynx, esophagus or soft tissues of the neck were excluded. The primary tumors in these cases comprised of four lung carcinomas, three colorectal carcinomas, a renal cell carcinoma, a pleural malignant mesothelioma, and an unknown primary. Therefore, it is important to keep intrathyroidal metastases in the differential diagnosis when evaluating a thyroid nodule, particularly in patients with a previous history of malignancy. Furthermore, a literature review reveals over 1,400 cases have been previously reported, with the most common malignancies from the kidney (34 %), lung (15 %), gastrointestinal tract (14 %), and breast (14 %).

Metastases to the thyroid: a review of the literature from the last decade

BACKGROUND

Although clinically evident metastases of nonthyroid malignancies (NTMs) to the thyroid gland are uncommon, it is important to suspect them in patients who present with a new thyroid mass and a history, however far back, of prior malignancy. In fact, metastases from NTMs to the thyroid gland have been reported in 1.4%-3% of all patients who have surgery for suspected cancer in the thyroid gland. Here we review the literature over the last decade regarding this topic.

SUMMARY

Based on recent literature, the most common NTMs that metastasize to the thyroid gland are renal cell (48.1%), colorectal (10.4%), lung (8.3%), and breast carcinoma (7.8%), and sarcoma (4.0%). Metastases of NTMs to the thyroid are more common in women than men (female to male ratio=1.4 to 1) and in nodular thyroid glands (44.2%). The mean and median intervals between diagnosing NTMs and their metastases to thyroid gland are 69.9 and 53 months, respectively. In 20% of cases the diagnosis of the NTM and its metastases to the thyroid was synchronous. Recent reports indicate that there is a higher frequency of sarcoma metastasizing to the thyroid gland than reported in prior years. Fine-needle aspiration biopsy (FNAB) of thyroid masses is useful in diagnosis of thyroid metastases. However, this requires information about the NTM so that the proper antibodies can be used for immunohistochemical analysis; therefore it is of lesser utility if the NTM is occult. In patients with preexisting thyroid pathology the FNAB diagnosis can be more difficult due to more than one lesion being present.

CONCLUSIONS

It is important to keep in mind that the thyroid gland can be a site of metastases for a variety of tumors when evaluating a thyroid nodule, especially in a patient with a prior history of malignancy. In patients with thyroid lesions and a history of malignant disease, regardless of time elapsed since the initial diagnosis of the primary neoplasm, disease recurrence or progression of malignancy must be considered until proven otherwise.

Tumors metastatic to thyroid neoplasms: a case report and review of the literature

Metastasis into a thyroid neoplasm-tumor-to-tumor metastasis-is exceedingly rare. We describe the 28th documented case of a tumor metastatic to a thyroid neoplasm and review the literature on tumor-to-tumor metastasis involving a thyroid neoplasm as recipient. All cases showed a recipient thyroid neoplasm with an abrupt transition to a morphologically distinct neoplasm. Metastasis into primary thyroid neoplasm was synchronous in 33% of cases and metachronous in 67%. Follicular adenoma was the most common recipient thyroid neoplasm overall (16/28), and papillary thyroid carcinoma was the most common malignant recipient neoplasm (9/28). Of the 9 recipient papillary carcinomas, 6 were follicular variants. Renal cell carcinoma was the most common neoplasm to metastasize to a primary thyroid neoplasm (9/28), followed by lung (6/28), breast (5/28), and colon (3/28) carcinoma. Tumor-to-tumor metastasis should be considered whenever a dimorphic pattern is encountered in a thyroid tumor.

Tumor-to-tumor metastases to follicular variant of papillary thyroid carcinoma: histologic, immunohistochemical, and molecular studies of two unusual cases

Tumor-to-tumor metastasis in thyroid neoplasms is exceedingly uncommon. Two unusual cases of breast carcinoma and renal cell carcinoma metastatic to follicular variant papillary carcinoma are reported. On histologic sections, the donor tumor cells infiltrated the substance of the recipient tumor and the angiolymphatic channels, but the bulk of metastatic tumor was confined within the thyroid carcinoma. Immunohistochemical stains as well as molecular studies confirmed the origin of both donor tumors, as well as the diagnosis of follicular variant of papillary carcinoma in the recipient tumors. Distinguishing between two such tumor populations may be difficult when the donor tumor cells morphologically resemble primary neoplasms of the recipient organ. A history of previous malignancy and ancillary studies can be helpful in making this distinction and rendering the correct diagnosis. A brief review of literature and discussion of tumor-to-tumor metastasis in thyroid neoplasms is also presented.

Tumor-to-tumor metastasis to a thyroid follicular adenoma as the initial presentation of a colonic adenocarcinoma

The incidence of thyroid involvement by metastatic disease from distant organs ranges from an average of 3.1% in surgical series to 5.3% in autopsy series. However, the metastasis of one tumor into another (traditionally referred to as 'tumor-to-tumor metastasis') is distinctly uncommon. Typically, they are identified as new manifestations or necropsy findings of a known, pre-existing donor tumor. Herein is described the case of a 59-year-old woman whose thyroid nodule (a follicular adenoma) was resected and found to contain foci of a well-differentiated adenocarcinoma with a morphologic and immunohistochemical profile consistent with origination from the lower gastrointestinal tract. Subsequent diagnostic work-up revealed a sigmoid colon tumor with metastases to the liver. This is, to the authors' knowledge, the first reported example of a colon adenocarcinoma whose initial clinical manifestation was a metastasis to a thyroid neoplasm and only the third reported example of a colonic adenocarcinoma metastatic to a thyroid tumor. In a review of previously reported examples of tumor-to-tumor metastases involving a thyroid neoplasm as the recipient, the following features were present in the majority: (i) multifocality of the metastatic tumor aggregates; (ii) a total lack of, or only minimal amounts of reaction (desmoplastic, inflammatory or myxoid) of the recipient tumor to the metastatic deposits; and (iii) retention of the histopathologic characteristics of the donor tumor in the metastatic deposits. In general, strikingly divergent morphologic features in an otherwise typical thyroid neoplasm should elicit a differential diagnosis that takes into consideration the possibility of metastasis.

Metastases of breast carcinoma to the uterus. Report of two cases, one harboring a primary endometrioid carcinoma, with review of the literature

BACKGROUND

Metastases to the uterus are rare, accounting for less than 10% of all cases of metastases to the female genital tract from extragenital cancers. The endometrium is even less frequently affected by metastases. Lobular carcinoma is the most common type of breast cancer that metastasizes to the uterus.

CASES

Two cases of infiltrating lobular carcinoma of the breast metastatic to endometrium and myometrium, one of them harboring an endometrioid adenocarcinoma, are reported. Both patients were on tamoxifen therapy and presented with uterine bleeding.

CONCLUSION

To the best of our knowledge, uterine carcinoma serving as recipient of metastatic carcinoma from the breast has not been previously documented. This possibility should be considered when an unusual bimorphic pattern appears in a tumor until proven otherwise.