"Intrasellar tumor-to-tumor metastasis: A single center experience with a systematic review".

PURPOSE: This study investigates the rare occurrence of tumor-to-tumor metastasis in Pituitary Neuroendocrine Tumors (PitNETs), also known as pituitary adenomas, aiming to enhance understanding of its diagnostic and therapeutic challenges. We report two cases from our institution of tumor-to-tumor metastasis involving PitNETs, followed by a systematic literature review. METHODS: We conducted a comprehensive literature review using PubMed and Google Scholar databases. This review provides insights into patient demographics, clinical presentations, primary tumor origin, management approaches and outcomes. RESULTS: We identified 38 documented cases of tumor-to-tumor metastasis involving the pituitary gland in the literature. This revealed a diverse range of primary tumor origins, with lung, breast, and renal carcinomas being the most prevalent. Clinical presentations varied, with visual disturbances emerging as the most frequently reported symptom. Surgical interventions predominantly resulted in subtotal resection. Kaplan-Meier survival analysis demonstrated that endoscopic endonasal approaches (EEA) are associated with longer median survival times compared to other surgical methods. CONCLUSION: Tumor-to-tumor metastasis to PitNETs must be considered in differential diagnoses of sellar masses. Prompt and accurate diagnosis, coupled with a multidisciplinary treatment strategy, is essential. Our study contributes to the scarce literature on such metastases, providing a foundation for further understanding of this complex pathological entity.

Metastatic melanoma involving a genetically confirmed angiofibroma of soft tissue: A previously unreported type of tumor-to-tumor metastasis.

Tumor-to-tumor metastases are an uncommon phenomenon and are very rare in the context of malignant melanoma. This case report describes a 73-year-old male who underwent an excision of a melanoma from his forehead. Six months later, he developed metastatic disease, including metastasis to a genetically confirmed angiofibroma of soft tissue of the abdominal wall. Angiofibroma of soft tissue is a relatively recently described benign fibrovascular soft tissue tumor, and there appear to be no previous reports of it being a recipient tumor for a metastasis. Awareness of the phenomenon of tumor-to-tumor metastasis and of the distinctive morphologic and molecular genetic features of angiofibroma are critical to avoid misdiagnosis of this very rare event as "dedifferentiated" melanoma.

Clinical, cytological, and pathological characteristics of metastatic renal cell carcinoma to the thyroid: A study of 14 cases at a Japanese single institution.

A preoperative diagnosis of metastatic renal cell carcinoma to the thyroid (MRCCT) is important for determining clinical management but is challenging even in cases with a clinical history of renal cell carcinoma (RCC). This study aimed to elucidate the clinical, cytological, and pathological characteristics of MRCCT. Fourteen MRCCT cases extracted from 18 320 malignant thyroid tumors were included in this study. Twelve MRCCT (85.7%) occurred as solitary lesions and the most frequently suspected lesions on ultrasonography were follicular tumors. On cytology, 46.2% of cases were reported as RCC or suspected RCC; a medical history of RCC and immunocytochemistry were helpful in interpretation. RCC metastasized to a follicular adenoma in 50.0% of the solitary lesions. MRCCTs with a long interval from the initial presentation, solitary lesion, and Ki-67 labeling index <10% showed significantly longer disease-free survival. MRCCT is characterized by a long interval from the initial presentation of RCC, appearance as a solitary nodule, ultrasonographic similarity to follicular tumors, sharing cytological findings with primary thyroid tumors, and high frequency of metastasis within follicular adenoma. A long interval from the initial presentation, occurrence as a solitary lesion, and low Ki-67 labeling index may be favorable prognostic factors.

Tumor-to-tumor spread: a case report and literature review of renal cell carcinoma metastasis into thyroid cancer.

Tumor-to-tumor metastasis is a rare, yet important entity. Patients with a history of renal cell carcinoma (RCC) may have tumor deposits to the thyroid gland preceding or following their initial cancer diagnosis for many years. The diagnosis can be challenging, and clinicians must remain suspicious of a newly found thyroid nodule in a patient with a history of RCC. In this review, we report a case of a patient with RCC who was incidentally found to have a thyroid nodule on surveillance imaging found to be consistent with tumor-to-tumor metastasis from RCC into papillary thyroid carcinoma. It is imperative to consider this diagnosis as the thyroid is the most common site of spread, and treatment with partial or total thyroidectomy has led to improved survival.

Tumor-to-Tumor Metastasis of Medullary Thyroid Carcinoma to Paraganglioma in a Multiple Endocrine Neoplasia Type 2B Patient: A Case Report and Literature Review.

Tumor-to-tumor metastasis is a rare phenomenon in which primary tumor cells metastasize to other tumors. Herein, we report an extremely rare case of tumor-to-tumor metastasis of medullary thyroid carcinoma to a paraganglioma in a patient with multiple endocrine neoplasia type 2B. Based on genetic examination, a 36-year-old woman was diagnosed with multiple endocrine neoplasia type 2B when she was 24 years old. She had a history of total thyroidectomy for medullary thyroid carcinoma and bilateral adrenalectomy for pheochromocytomas, which were performed when she was 15 years and 29 years old, respectively. Follow-up computed tomography demonstrated a retroperitoneal tumor of 30 mm in diameter beside the left kidney and a liver tumor of 16 mm in diameter located in segment 6. The retroperitoneal and liver tumors were surgically resected and examined by a pathologist. Histological examination revealed the classic Zellballen pattern in the retroperitoneal tumor, rendering the diagnosis of a paraganglioma recurrence. Inside the tumor, a white nodule positive for carcinoembryonic antigen, weakly positive for calcitonin, and negative for tyrosine hydroxylase, was identified and diagnosed as a metastatic medullary thyroid carcinoma with high malignant potential. The liver lesion was diagnosed as a metastasis of the medullary thyroid carcinoma. This is the first report of tumor-to-tumor metastasis of medullary thyroid carcinoma to paraganglioma in a patient with multiple endocrine neoplasia type 2B twenty years after total thyroidectomy.

Collision tumor of meningioma and metastatic renal clear cell carcinoma: a case report.

Distinct tumors in direct contact with one another are known as collision tumors and collision tumors of meningioma and metastatic renal cell carcinoma have not been previously reported. We report a 71-year-old female with a history of renal cell carcinoma who was presented with slow response and gait imbalance for 4 months. Brain MRI showed a mass in the base of right middle cranial fossa. The mass was completely removed. Histopathologic and radiographic findings provided evidence for a collision composed of meningioma and metastatic renal clear cell carcinoma.

Tumor-to-tumor metastasis of diffuse large B cell lymphoma to gastric adenocarcinoma via CXCL12 (SDF-1)/CXCR4 axis: a case report.

BACKGROUND: Tumor-to-tumor metastasis is the rare phenomenon in which one tumor exhibits metastatic deposits from another. To the best of our knowledge, there has been no prior reported case of tumor-to-tumor metastasis of a diffuse large B cell lymphoma (DLBCL) to a primary gastric adenocarcinoma. CASE PRESENTATION: A 70-year-old man presented with chest discomfort. An echocardiogram showed the presence of a right ventricular tumor. A positron emission tomogram showed multiple foci of abnormal activity in right cervical lymph nodes, cardiac wall, and stomach. A right cervical lymph node biopsy specimen revealed histological features of DLBCL. An esophagogastroduodenoscopy showed a large circumferential ulceration on the gastric body. Subsequent biopsy revealed adenocarcinoma cells surrounded by infiltrating lymphoma cells. On immunohistochemical staining, lymphoma cells were positive for CXCR4 and adenocarcinoma cells were positive for CXCL12/SDF-1. The patient was treated with six cycles of R-CHOP chemotherapy regimen, resulting in a complete remission. CONCLUSIONS: This patient's case implies that the interaction between a chemokine and its receptor may be the underlying mechanism for the observed tumor-to-tumor metastasis. Specifically, our case would suggest an involvement of the CXCL12 (SDF-1)/CXCR4 axis in the observed metastasis of DLBCL to primary gastric adenocarcinoma.

Breast cancer metastasis into thyroid papillary carcinoma: A case report.

Both metastatic tumors and breast cancer metastases in the thyroid gland are rare. Tumor metastasis into a primary thyroid cancer is rarer. We present a case with breast cancer metastasis into a metachronous thyroid papillary carcinoma which is the only case in literature.

Metastatic rectal cancer to papillary thyroid carcinoma: a case report and review of literature.

BACKGROUND: Tumor-to-tumor metastasis is a rare event. Rectal cancer to primary thyroid neoplasm metastasis is extremely rare. Herein, we reported a case of metastatic rectal adenocarcinoma to a papillary thyroid carcinoma. The incidence and clinicopathological characteristics of metastatic colorectal cancer to a thyroid gland neoplasm were described, and the pertinent literature was reviewed. CASE PRESENTATION: A 34-year-old female patient had curative treatment of initial rectal adenocarcinoma in 2012, and was found to have lung metastases by follow-up CT scan 3 years later. In 2018, she was found to have thyroid metastasis by imaging due to left neck pain and hoarseness. A fine-needle aspiration biopsy (FNAB) result suggested suspicious papillary thyroid carcinoma (PTC). The patient underwent a total thyroidectomy and bilateral cervical lymph nodes dissection. The histopathology of thyroidectomy specimen revealed a rectal adenocarcinoma metastatic to the thyroid concomitant with the papillary carcinoma in metastatic adenocarcinoma. The patient received levothyroxine supplementation therapy and palliative chemotherapy with irinotecan and anti-angiogenesis for the metastatic rectal adenocarcinoma. After 1 year of thyroidectomy, no newly developed lesion evidence of recurrent PTC was observed. The patient remains still alive. CONCLUSION: The possibility of metastases should be considered in patients with a history of rectal cancer and with a thyroid lesion, particularly in those with ageing, hereditary nonpolyposis colorectal cancer (HNPCC) or long-term survival. The diagnosis should be histologically confirmed for the presence of both primary thyroid lesions and secondary thyroid neoplasms. Thyroidectomy may be a feasible treatment for symptomatic thyroid metastasis or thyroid cancer. we need to gain more available evidence from large or multi-center clinical data to help clinicians to diagnose rectal cancer to thyroid neoplasm metastases and evaluate treatment.

The Pituitary Tumors and Their Tumor-Specific Microenvironment.

Pituitary tumors develop within a macroenvironment and microenvironment that favor their overall survival. Given the pituitary gland's unique anatomic, histological, and physiological properties, the role of the TME in the pituitary tumors is central. This chapter summarizes the body of literature investigating the role of each component of the TME in relation to tumors of the pituitary and its intimate association with tumorigenesis, maintenance, and progression.

Unexpected tumor-to-tumor metastasis of synovial sarcoma within leiomyoma: A case report and literature review.

A tumor metastasis within another tumor is known as tumor-to-tumor metastasis (TTM). We report a 43-year-old woman who presented with hypermenorrhea and an abdominal mass. She had history of a soft tissue tumor on her left ankle at 38 years of age. Laboratory data showed slight elevation of CA125 and no other abnormal findings and magnetic resonance imaging revealed a circumscribed margin mass in the uterine fundus. We diagnosed the mass as benign leiomyoma and performed total laparoscopic hysterectomy. Postoperative pathological examination revealed TTM of synovial sarcoma within the uterine leiomyoma. A database search identified 29 cases of TTM within uterine leiomyoma. The donor tumor was mostly breast cancer (in 23 cases). To the best of our knowledge, this is the first report of a sarcoma TTM to a uterine leiomyoma. Despite the difficulty of preoperative diagnosis, TTM should be considered during the treatment approach for a patient with leiomyoma and a history of malignant tumors.

Glioblastoma with tumor-to-tumor metastasis from lung adenocarcinoma.

Glioblastoma is a tumor with widely variable morphology. It may rarely show pseudoepithelial components or true epithelial differentiation. Metastasis to glioblastomas have been previously reported, but were unsupported by immunohistochemical or molecular analyses. Herein we describe a glioblastoma with carcinomatous foci in a patient with no past clinical history of tumors outside the central nervous system. The carcinomatous foci expressed epithelial, but not glial markers. Therefore, whole-body imaging was carried out to verify the presence of carcinoma. A lung mass was biopsied and it resulted as primary lung adenocarcinoma. Carcinomatous foci of glioblastoma and lung adenocarcinoma had the same KRAS mutation which was absent in glial areas of the glioblastoma. Thus, glioblastoma with tumor-to-tumor metastasis was diagnosed. This case demonstrates that, albeit rare, metastases to glioblastoma may occur, and they should be considered in the differential diagnosis of glioblastoma with carcinomatous foci. Even when the past clinical history is negative, the presence of carcinoma should be investigated to rule out glioblastoma with tumor-to-tumor metastasis.

Hickam's dictum: Angiosarcoma-to-meningioma metastasis.

Tumor-to-tumor metastasis is a seldom reported phenomenon whereby a neoplasm seeds within another histologically distinct tumor, with only 84 cases documented in the literature. We hereby describe the case of a 95-year-old woman who died of widespread metastases identified as a primary hepatic angiosarcoma on autopsy, and the interesting finding of a seeding foci within a dural meningioma. Although meningiomas are the most common intracranial neoplasms to harbor such a phenomenon, this is to our knowledge the first case where an angiosarcoma was identified as the donor tumor.

A rare case of cancer-to-cancer metastasis: breast cancer to renal cell cancer : Case report and review of literature.

BACKGROUND: Cancer-to-cancer metastasis is very rare with less than 50 cases described in literature. This article reports a case of breast cancer with synchronous metastasis to clear cell renal cell cancer. CASE DESCRIPTION: A 79-year-old woman was diagnosed with a bilateral breast carcinoma. Sonographic staging investigation of the abdomen revealed a 6 cm wide expansion of the right kidney. Bilateral mastectomy and nephrectomy of the right kidney was performed. The histology revealed a clear cell renal cell carcinoma and in the center of the tumor a 0.5 cm metastasis of the breast cancer. The patient's comorbidities and performance status precluded chemotherapy und she received palliative radiotherapy, targeted monoclonal antibody therapy and antihormonal treatment. CONCLUSIONS: Even if cancer-to-cancer metastasis is a very rare phenomenon, the simultaneous or consecutive finding of a renal tumor in women with breast cancer should be carefully evaluated.

Gastric cancer metastatic to neck lipoma: a case report with imaging consideration.

A 71-year-old man visited our hospital for examination of a soft neck mass. Computed tomography and magnetic resonance imaging scans showed a well-circumscribed large lipomatous tumor with multiple nodules inside. Atypical lipomatous tumor or lipoma involving the lymph nodes was considered. Pathological examination of the surgical specimen suggested typical lipoma including multiple metastatic foci from gastric cancer. Subsequent endoscopy revealed a gastric tumor, which was histologically proven to be signet-ring cell carcinoma. Considering these findings, this case was diagnosed as tumor-to-tumor metastasis to lipoma. We present the first such case with imaging and clinical characteristics.

Tumor-to-tumor metastasis of lung adenocarcinoma into a spinal intradural solitary fibrous tumor: a case report.

Solitary fibrous tumors (SFTs) are rare mesenchymal neoplasms commonly involving visceral or parietal pleura. We present the first report of tumor-to-tumor metastasis involving a pulmonary adenocarcinoma donor and an intradural SFT recipient. The patient presented with a 1 year history of diffuse back pain. A spinal intradural contrast-enhancing mass at the T9/10 level and a tumor of the lung were diagnosed radiologically. Bronchoscopic biopsy confirmed pulmonary adenocarcinoma in the right upper lung lobe. Due to deteriorating neurological status with conus medullaris syndrome, we performed a neurosurgical excision of the lesion. Histological analysis of the tumor revealed tumor-to-tumor metastasis of the adenocarcinoma to the SFT.

Tumor-to-Tumor Metastasis - a Unique Case of Clear Cell Renal Cell Carcinoma Harboring Metastasis of Adenocarcinoma of Unknown Origin.

BACKGROUND: The tumor-to-tumor metastasis is exclusively rare finding, in which one malignant neoplasia metastasizes to another tumor of different origin. CASE: The author describes an 68-year-old woman, who was found to have a solitary tumor in the right kidney, as well as multiple tumor nodules in the liver. She underwent a radical nephrectomy. A histology of lesion in the kidney revealed a conventional clear cell renal cell carcinoma (RCC) harboring multiple metastatic foci of another adenocarcinoma. At that time, there was not possible to reliably specify a primary source. Subsequently, a probatory excision of tumor lesion in the liver was also done. A microscopy confirmed an adenocarcinoma with a similar appearance as found in RCC. Due to unfavourable health condition, a paliative chemotherapy could not be realized and the patient died shortly thereafter. A primary origin of adenocarcinoma remained unclear. CONCLUSION: A unique case of metastatic adenocarcinoma is described, that was initially diagnosed as an incidental finding within a clear cell RCC of the kidney. Such unexpected feature may represent a great diagnostic challenge for both, pathologist and clinician. From a prognostic point of view, an evidence of intratumoral cancer metastasis within a primary RCC is usually an indicator of disseminated oncologic disease with a poor outcome. Key words: tumor-to-tumor metastasis - donor - recipient - renal cell carcinoma.

Renal cell carcinoma metastasizing to pancreatic neuroendocrine neoplasm - the second case described in the world literature.

Tumor-to-tumor metastases are very rare events. We report a case of a 64-year-old man who presented with a tumor of the pancreas. The patient underwent partial pancreatectomy. Frozen section diagnosis of the tumor was an endocrine neoplasm. Paraffin block slide examination revealed a tumor consisting of two components: pancreatic endocrine neoplasm at the periphery of the tumor and the central part composed of clear cells with delicate vessels. The results of immunohistochemical stains revealed renal cell carcinoma surrounded by pancreatic endocrine neoplasm, therefore representing an unusual case of renal cell carcinoma metastasizing to a pancreatic endocrine neoplasm.

Metastatic pancreatic neuroendocrine tumor to the central nervous system in a patient with von Hippel-Lindau disease: A case report and literature review.

Pancreatic neuroendocrine tumor (NET) is frequently encountered in patients with von Hippel-Lindau disease (VHL) and uncommonly metastasizes to the central nervous system. Here, we present the case of a VHL patient with symptomatic pancreatic NET metastases to both the cervical spinal cord and a preexisting brainstem hemangioblastoma (e.g., tumor- to-tumor metastasis).

[Tumor-to-tumor metastasis in a renal carcinoma: A rare and surprising event]. / Métastase d'une tumeur primitive dans un carcinome rénal : un évènement rare et surprenant.

Tumor-to-tumor metastasis is a very rare event. We report three cases of tumor metastasizing in a clear cell renal cell carcinoma: two breast carcinomas and a sigmoid carcinoma. So we objectified a prevalence of 1.5% of renal tumors in our series. It's a rare situation but to be considered in daily practice because it changes oncological management offered to the patient. According to the literature, clear cell renal cell carcinoma is the most common tumor recipient of metastasis. Several physiopathological mechanisms can explain this phenomenon, but many of them are still unknown. A better understanding of this phenomenon makes it possible to improve the diagnosis and thus the management of patients with several cancers.