"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.

Tumor-to-Tumor Metastasis: Dissemination of Cutaneous Squamous Cell Carcinoma Involving Parotid Warthin Tumor-Case Report.

Warthin tumors (WTs) are the second most common salivary gland tumors, most commonly found in the tail of the parotid gland. The lymphoid components of a WT may also serve as a site for tumor-to-tumor metastasis. This report describes the metastasis of cutaneous squamous cell carcinoma (cSCC) from the preauricular region to a parotid WT. A 68-year-old male patient was admitted to the Department of Cranio-Maxillofacial Surgery of the Jagiellonian University in Cracow, Poland, with a two-year history of a growing, painless skin tumor of the right preauricular region. The patient was eligible for surgical treatment with elective neck dissection at the Va, III, II, I levels with parotidectomy and the excision of the cSCC. In the histopathological examination of the components of the surgical specimen beside the primary cutaneous squamous cell carcinoma (cSCC), a parotid WT was found; in the majority, it was occupied and destroyed by the metastatic cSCC and radically removed. After a tumor board consultation, due to the advanced stage (pT3N2b LVI2 PNI0 R0), with three intraparotid lymph node metastases and LVI2, the patient was authorized for postoperative radiotherapy. In conclusion, tumor-to-tumor metastasis is an extremely rare entity. Surgery is the standard of care for both WTs and head and neck cSCC. In most cases, metastasis into the parotid gland can be successfully treated with superficial parotidectomy with facial nerve preservation. Dissemination into the parotid gland requires elective neck dissection, as well as adjuvant treatment.

Case report: Isolated oligometastatic disease of the prostate from a primary lung adenocarcinoma.

Secondary prostate cancer typically occurs from direct seeding of a renal or bladder tumor. Metastasis via hematogenous spread is exceedingly rare and is typically identified incidentally at autopsy. This report describes a 72-year-old male with lung adenocarcinoma initially staged as Stage IA2 who developed oligometastatic disease of the prostate. He was initially treated with radiation therapy and was found to have a hypermetabolic focus in the prostate gland during surveillance PET/CT imaging 6 months following treatment. Subsequent biopsy revealed metastatic lung adenocarcinoma in 6/6 core samples, leading to diagnosis of oligometastatic disease of the prostate. To our knowledge, this is the first report of isolated oligometastatic disease to the prostate from a primary lung adenocarcinoma.

Metastasis of Rectal Signet Ring Cell Carcinoma to Typical Lipoma: A Rare Presentation of the Tumor-to-Tumor Metastasis Phenomenon.

Rectal signet ring cell carcinoma represents a rare subtype of colorectal adenocarcinoma known for its aggressive biological nature and poor prognosis. Although the co-occurrence of colorectal carcinoma with other tumors has been reported, the uncommon phenomenon of tumor-to-tumor metastasis, first described in 1930, remains rare. The most frequent donor neoplasms are lung or breast carcinomas, whereas cerebral meningiomas have been reported to be the most frequent recipient neoplasms. Here we report a case of a typical lipomatous tumor harboring metastatic signet ring cell rectal carcinoma. It is about a 42-year-old man diagnosed with rectal signet ring cell carcinoma and treated with concurrent radiotherapy and chemotherapy followed by an anterior resection and manual coloanal anastomosis with a temporary ileostomy. During the surgery, an abdominal wall lipoma was discovered and excised. A histopathological examination revealed infiltration of the fibro adipose tissue by a mucinous adenocarcinoma with a contingent of signet ring cells. The patient died 12 months after adjuvant chemotherapy due to peritoneal progression. To the best of our understanding, this represents the initial documented instance of tumor-to-tumor metastasis from rectal signet cell carcinoma to a conventional nonvascular lipoma. Consequently, even if one of these tumors appears clinically and radiologically benign, it is prudent to entertain the prospect of tumor-to-tumor metastasis. Thus, a comprehensive pathologic study of both tumors is highly recommended.

A rare case of tumor-to-tumor metastasis of esophageal adenocarcinoma into meningioma.

Tumor-to-tumor metastasis is a known but rare occurrence and is characterized as 2 distinct tumor types in same anatomic location. We present a rare case of intracranial tumor-to-tumor metastasis of esophageal adenocarcinoma into meningioma. Our case emphasizes the rare occurrence of intracranial tumor-to-tumor metastasis and importance of histology and immunohistochemical analysis in distinguishing between metastasis and meningioma, especially when faced with ambiguous demarcation. Awareness of this occurrence is crucial, given that metastases might be the initial indication of an underlying tumor and it can impact the clinical management decisions.

A Rare Case of Tumor-to-Tumor Metastasis: Renal Cell Carcinoma Metastasis to Papillary Thyroid Carcinoma.

Papillary thyroid carcinoma (PTC) is the most common thyroid malignancy. Renal cell carcinoma (RCC) metastasis to the thyroid, albeit the most common carcinomatous metastasis to the thyroid, is rare, and tumor-to-tumor metastasis of RCC to PTC is even rarer. We present a case of a 65-year-old male with a history of RCC who presented with a thyroid nodule 7 years after left radical nephrectomy. Imaging showed the thyroid nodule predating the kidney tumor. Fine-needle aspiration biopsy was performed and showed 2 distinct cell populations, 1 of which was stained with RCC markers and another that was stained positively for thyroid markers. An interpretation of atypia of undetermined significance was rendered and molecular testing was indeterminate with ThyGeNEXT not detecting mutations and ThyraMIR positive for a level 2 microRNA pattern consistent with low risk for malignancy. The patient elected for active surveillance until follow-up thyroid ultrasound showed continued growth. At this point, a right hemithyroidectomy was performed. Pathology confirmed clear cell RCC metastasis to an infiltrative follicular variant papillary thyroid carcinoma. This case highlights the possibility of tumor-to-tumor metastasis in patients with a previous history of RCC even years after nephrectomy and in the absence of other metastatic lesions.

Mucin-Producing Lobular Breast Carcinoma Metastasis to an Ovarian Fibroma: Histopathological and Immunohistochemical Analysis of a Rare Case and Literature Review.

Breast cancer stands as the primary cause of cancer-related mortality among women worldwide, often presenting with distant metastases upon diagnosis. Ovarian metastases originating from breast cancer represent a range of 3-30% of all ovarian neoplasms. Case Report: Herein, we present the histopathological, histochemical, and immunohistochemical findings of a rare case involving mucin-producing lobular breast carcinoma metastasizing to an ovarian fibroma in an 82-year-old female previously diagnosed with lobular breast carcinoma. Histopathological examination of the excised tissues revealed a biphasic neoplasm characterized by tumor cells expressing AE-1/AE-3 cytokeratin, mammaglobin, GCDFP-15, inhibin, and calretinin. Positive mucin staining was observed using histochemical techniques, and reticulin fibers were demonstrated using the Gordon-Sweets technique. A final diagnosis of mucin-producing lobular breast carcinoma metastatic to a benign ovarian fibroma was rendered. Conclusion: The occurrence of metastatic breast carcinoma overlaid on an ovarian tumor represents a rare and diagnostically challenging scenario.

Tumor-to-Tumor Metastasis of Lung Cancer to Kidney Cancer: A Review of the Literature and Our Experience.

Tumor-to-tumor metastasis (TTM) is a rare phenomenon documented in patients with multiple primary cancers. This condition is defined as a metastasis between two true primary tumors. The most frequently reported recipient tumor is renal cell carcinoma (RCC), and the lung carcinomas are the most common metastatic tumor donors. Therefore, this paper attempts to address the current gap in knowledge about this rare phenomenon. The first part of this review outlines the recently proposed models and mechanisms involved in the TTM process. The second part then summarizes and analyzes previous case reports in the literature. We also present our experience with the case of lung cancer that metastasized into RCC. Given the sporadic incidence of TTM, no specific management guidelines exist. Therefore, considering TTM in patients with multiple primary tumors is important as it could potentially modify the oncological management offered.

Metastasis of Clear Cell Renal Cell Carcinoma to Uterine Leiomyoma: First Case Report and Review of Literature.

Metastasis of clear cell renal cell carcinoma (clear cell RCC) to the gynecologic tract is infrequent, and involvement of the uterus is extremely rare. A review of the literature identified a total of 12 reported examples with metastasis to the uterine serosa (1), endometrium (5), cervix (5) and only one with metastasis to the myometrium. This report represents the first case of tumor-to-tumor metastasis involving a clear cell RCC with metastasis to a uterine leiomyoma. The patient was a 50-year-old woman status post-radical nephrectomy for newly diagnosed unilateral clear cell RCC (stage pT3a) with negative margins, who subsequently underwent a total abdominal hysterectomy and bilateral salpingo-oophorectomy for the incidental finding of multiple uterine masses measuring up to 14.5 cm suggestive of fibroid on pelvic ultrasound. The pathologic exam of the specimen was consistent with metastatic clear cell RCC (1.2 cm) to uterine leiomyoma, confirmed with keratin, vimentin, CD10, CA9, and PAX8 immunohistochemistry. The patient's postoperative course was uneventful, and no new lesions were identified at follow-up during the past 6 months.

Adenocarcinoma of sigmoid colon with metastasis to an ovarian mature teratoma: A case report.

BACKGROUND: Colorectal cancer ranks third in global cancer-related mortality, often due to metastases to liver and lungs. Ovarian metastases are less common, accounting for 3.6% to 7.4% of cases. In contrast, mature ovarian teratomas are frequently benign. Tumor-to-tumor metastasis is a rare phenomenon, with a limited number of documented cases. Three cases of mature ovarian teratomas metastasizing from different cancers have been reported. This report focuses on a case of tumor-to-tumor metastasis from sigmoid colon adenocarcinoma to a mature ovarian teratoma. CASE SUMMARY: A 41-year-old Taiwanese woman with no known systemic diseases presented with lower back pain, which led to imaging revealing malignant lesions in the spine, pelvis, liver, and multiple lung metastases. She was diagnosed with sigmoid colon adenocarcinoma with metastases to the liver, lung, bone, and a left ovarian teratoma. Treatment involved radiotherapy and chemotherapy, resulting in regression of the primary tumor and stable lung and liver lesions. Due to abdominal symptoms, she underwent exploratory surgery, unveiling a mature teratoma in the left ovary with signs of metastatic adenocarcinoma. CONCLUSION: Consider resecting mature ovarian teratomas with concurrent colorectal adenocarcinoma to prevent tumor-to-tumor metastasis.

Glioblastoma with Probable Intratumoral Adenocarcinoma Metastasis: A Rare Report with Review of Literature.

"Tumor-to-tumor metastasis," an uncommon phenomenon, refers to a primary tumor metastasis into another tumor, with the most frequent donor being lung carcinoma and common recipients being renal cell carcinoma and meningioma. Tumor-to-tumor metastasis occurring in gliomas is rare with less than 20 reports described so far, and that into a glioblastoma is even rarer. We report a 54-year man, diagnosed with glioblastoma, IDH-wildtype, with metastasis of an adenocarcinoma into it. On histomorphology, the glial component was composed of astrocytic cells and showed increased mitosis, microvascular proliferation, and focal necrosis. This was intermingled with an adenocarcinomatous tumor with pleomorphic epithelial cells in glands, nests, and sheets. On immunohistochemistry, the adenocarcinomatous areas were positive for AE1/AE3 and TTF1 but negative for glial markers, ruling out adenoid glioblastoma. Further cytogenetic analysis showed EGFR amplification in the glial component but not in the adenocarcinoma component, ruling out glioblastoma with true epithelial metaplasia, and supporting the diagnosis of adenocarcinoma metastasis into glioblastoma. Glioblastomas may be susceptible to intratumoral metastasis due to the proliferating leaky vascular channels, however, the short survival of patients with glioblastoma may be responsible for the rarity of this occurrence. The documentation of these tumors is important as they may be important for clinical diagnosis and further treatment and prognosis.

Metastasis infiltrating tumor to meningioma: a case report.

BACKGROUND: There have been many reports of tumor-to-tumor metastasis, in which cancer metastasizes directly into meningiomas. However, metastasis infiltrating tumors in which cancer metastasizes around meningiomas are rare. Therefore, we report a case of metastasis originating from lung cancer that infiltrated meningioma. CASE PRESENTATION: A 79-year-old Japanese woman underwent head magnetic resonance imaging for brain metastasis screening before lung cancer surgery. At that time, asymptomatic meningioma of the left frontal region was accidentally found. Magnetic resonance imaging 6 months later revealed a lesion suspected to be a metastatic brain tumor close to the meningioma. Brain tumor resection was performed, and histopathological diagnosis was meningioma and metastatic brain tumor. Metastatic cancer had invaded the meningioma at the boundary between the brain tumor and metastasis. CONCLUSIONS: A sudden change in imaging findings on routine examination of meningiomas in patients with lung carcinoma may indicate a metastatic brain tumor. The form of cancer metastasis to meningioma is not limited to tumor-to-tumor metastasis, but also includes metastasis infiltrating tumors near the meningioma.

Caso Clínico: Metástasis Tumoral a Tumor- Un Raro Fenómeno / Clinical Case: Tumor to Tumor Metastasis - A Rare Phenomenon

Introducción: La metástasis tumor a tumor es muy rara con menos de 50 casos descritos en la literatura. Este artículo informa de un caso de metástasis de cáncer de mama en un tumor renal de células claras. Caso clínico: El caso corresponde a una mujer de 61 años de edad con antecedente de cáncer de mama, libre de enfermedad por 23 años. Por control, se solicita Tomografía computarizada (TC) simple y contrastada observándose a nivel de pelvis renal izquierda imagen nodular hipercaptante heterogénea de 2.4 cm, de bordes definidos, no infiltrante a tejidos adyacentes. Evolución: por localización de lesión, la paciente fue sometida a nefrectomía radical izquierda. El examen patológico demostró un carcinoma de mama metastásico de 3 mm, mal definido, dentro de un carcinoma de células renales claras de 2,5x2x2cm. Desenlace: continúa en seguimiento por consulta externa de oncología clínica. Conclusión: Este caso pone de relieve la importancia de los antecedentes previos de neoplasia maligna de un paciente, así como del muestreo adecuado de las neoplasias renales

Introduction: Tumor to tumor metastasis is very rare with less than 50 cases described in the literature. This article reports a case of breast cancer metastasis in a clear cell renal tumor. Clinical case: The case corresponds to a 61-year-old woman with a history of breast cancer, disease free for 23 years. For control, simple and contrasted computed tomography (CT) is requested, observing at the level of the left renal pelvis, a heterogeneous hypercapting nodular image of 2.4 cm, with defined edges, not infiltrating adjacenttissues. Evolution: Due to the location of the lesion, the patient was subjected to left radical nephrectomy. The pathological examination showed a poorly defined 3 mm metastatic breast carcinoma within a clear renal cell carcinoma of 2.5x2x2cm. Outcome: the patient continues to be followed by an outpatient clinic for clinical oncology. Conclusion: This case highlights the importance of a patient's previous history of malignancy, as well as adequate sampling of renal neoplasms

Tumor de Krukenberg del ovario asociado a teratoma maduro / Krukenberg tumor of the ovary associated with mature teratoma

Se reporta un caso excepcional de tumor de Krukenberg ovárico bilateral asociado a teratoma maduro encontrado en una mujer de 54 años. La ecografía mostró al lado derecho tumor ovárico sólido de 55 mm y al lado izquierdo tumor quístico de 125 mm. Se realizó histerectomía total, salpingooforectomía bilateral, resección del epiplón mayor y muestras peritoneales. Al tercer día postcirugía, la paciente presentó signos de tromboembolismo pulmonar masivo y aunque recibió terapia anticoagulante falleció al quinto día postoperatorio. El estudio histológico mostró infiltración masiva de carcinoma de células en anillo positivas para citoqueratina en ambos ovarios. El ovario derecho mostró la forma sólida clásica del tumor de Krukenberg mientras que el ovario izquierdo correspondió a un quiste dermoide con infiltración tumoral de carcinoma de células en anillo en la pared.

An exceptional case of bilateral Krukenberg tumor of the ovary associated with mature teratoma presented in a 54 years old patient is reported. The ultrasound showed a 55 mm solid right ovarian tumor and a 125 mm left cystic ovarian tumor. Hysterectomy and bilateral salpingoophorectomy was performed including omental resection and peritoneal biopsies. Massive pulmonary embolism was detected in the third day after the surgery. Even anticoagulant therapy was established the patient died in the fifth postoperative day. The histological study revealed massive infiltration of signet ring cell carcinoma with positive expression for cytokeratin in both ovaries. The right ovary showed the classical solid form of the tumor. The left ovary was a dermoid cyst with signet ring cell carcinoma infiltrating the cystic wall.

Non Small Cell Carcinoma Metastasis to Meningioma

"Tumor-to-tumor" metastasis is a rare event; meningioma has been reported as the most common primary intracranial tumor to harbor cancer metastases. Several hypotheses have been previously proposed to explain this occurrence, but the exact mechanism by which these metastases develop into meningiomas is not yet understood. Magnetic resonance imaging and spectroscopy have been valuable diagnostic tools, but preoperative diagnosis of metastasis to meningioma remains highly difficult. We present a case report of a metastasis of non-small cell lung cancer into an intracranial meningioma.

Papillary Carcinoma of Thyroid Metastatic to Adenocarcinoma In Situ of Lung: Report of an Unusual Case

The tumor-to-tumor metastasis is a rare event. The lung tumors are the most common donor tumors in tumor-to-tumor metastasis, but are exceedingly rare as a recipient. Here, we report a case of papillary thyroid carcinoma (PTC) metastasizing to adenocarcinoma in situ (AIS, formerly bronchioloalveolar carcinoma) of the lung in a 44-year-old woman who underwent total thyroidectomy for PTC 8 years ago. To the best of our knowledge, the present case is the first case reporting on PTC metastasized to AIS. A review of the relevant literature is presented.

Papillary Carcinoma of Thyroid Metastatic to Adenocarcinoma In Situ of Lung: Report of an Unusual Case

The tumor-to-tumor metastasis is a rare event. The lung tumors are the most common donor tumors in tumor-to-tumor metastasis, but are exceedingly rare as a recipient. Here, we report a case of papillary thyroid carcinoma (PTC) metastasizing to adenocarcinoma in situ (AIS, formerly bronchioloalveolar carcinoma) of the lung in a 44-year-old woman who underwent total thyroidectomy for PTC 8 years ago. To the best of our knowledge, the present case is the first case reporting on PTC metastasized to AIS. A review of the relevant literature is presented.

A case of hepatocellular carcinoma combined with solitary parathyroid metastasis / 대한내과학회지

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide1). Extrahepatic metastasis of HCC is now increasing due to prolonged survival. Most extrahepatic HCC occurs in patients with advanced stages. The lung, abdominal lymph nodes, and bone are common sites of extrahepatic metastasis. However, the parathyroid gland has not been reported as a metastatic focus. We report the first case of parathyroid metastasis as the first single metastasis site of HCC and microscopic tumor-to-tumor metastasis to a parathyroid adenoma.

Adenocarcinoma primario de pulmón metastásico a schwannoma: un caso de metástasis de tumor a tumor / Tumor-to-tumor metastasis: pulmonary adenocarcinoma metastatic to Schwannoma

The coexistence of multiple primary malignant tumors in the same host is not unusual; however, tumor-to-tumor metastasis is rare. According to previous publications, the most common recipient tumor is renal cell carcinoma, and lung carcinoma is the most frequent donor site. According our bibliographic search we are presenting the first published case of primary pulmonary moderately differentiated adenocarcinoma metastatic to a schwannoma, demonstrated with Thyroid Transcription Factor 1 (TTF-1); immunostaining has become an important tool for guiding diagnosis of adenocarcinoma.

La coexistencia de múltiples tumores malignos primarios en un huésped no es un evento infrecuente. Sin embargo, la presencia de una neoplasia con metástasis en otra neoplasia (metástasis de tumor a tumor) es una entidad inusual, según lo publicado en la literatura el tumor receptor más frecuente es el carcinoma de células renales y el donante el carcinoma de pulmón. En el siguiente reporte se presenta un caso de adenocarcinoma moderadamente diferenciado metastásico a schwannoma, donde por inmunomarcaje con el Factor 1 de Transcripción Tiroidea (TTF-1) se demostró el origen pulmonar de la lesión, este correspondería al primer caso según nuestra revisión bibliográfica.

Brain Metastasis of Renal Cell Carcinoma in Von Hippel-Lindau Disease

Although brain metastasis of renal cell carcinoma is a major cause of death in Von Hippel-Lindau disease(VHL), it is not easy to distinguish local recurrence of hemangioblastoma from distant metastasis. In addition, heman-gioblastoma has several characteristics suitable for recipient of "tumor-to-tumor metastasis". Authors report a case of Von Hippel-Lindau disease that had metastases of renal cell carcinomas.