Tumor-to-tumor metastasis: an extremely rare combination with renal cell carcinoma as the donor and a pancreatic neuroendocrine tumor as the recipient

Background Tumor-to-tumor metastasis is a rare phenomenon in which primary tumor cells metastasize hematogenously into another tumor. Herein, we report an extremely rare case of a renal cell carcinoma metastasis into a pancreatic neuroendocrine tumor exhibiting a tumor-to-tumor metastasis. Ours is the third reported case worldwide. Case presentation The patient, a 72-year-old male, was referred to our hospital for further examination and treatment due to high levels of prostate-specific antigen. A left renal tumor and pancreatic head tumor were revealed incidentally on screening computed tomography. There were suspected to be a renal cell carcinoma and primary pancreatic neuroendocrine tumor or pancreatic metastasis from the renal cell carcinoma according to preoperative examination. The left nephrectomy and subtotal stomach-preserving pancreaticoduodenectomy were performed because of the pancreatic tumor indicated for operation in either case of diagnosis. Postoperative pathological examination showed a diagnosis of clear cell renal cell carcinoma for the left renal tumor. The pancreatic tumor was diagnosed with clear cell renal cell carcinoma metastasis into the pancreatic neuroendocrine tumor, that is to say tumor-to-tumor metastasis. Conclusion In some cases, conservative approach is selected for pancreatic neuroendocrine tumor patients who meet some requirements. However, if such patients exhibit tumor-to-tumor metastasis which combines with renal cell carcinoma and pancreatic neuroendocrine tumor as this case, conservative approach leads to progression of renal cell carcinoma. Therefore, conceiving the possibility of tumor-to-tumor metastasis, it is necessary to carefully choose a treatment plan for pancreatic neuroendocrine tumor patients associated with renal cell carcinoma, not easily choosing conservative approach.

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 in a Renal Carcinoma Pulmonary Metastasis: A Rare Example of Tumor-to-Tumor Metastasis

The tumor-to-tumor metastasis phenomenon remains fairly uncommon, with fewer than 100 cases described to present time. Virtually any tumor can be a donor or a recipient neoplasm. Nevertheless, renal carcinomas have been implicated as the most common malignant tumors to harbor metastasis, while lung and breast tumors are the most frequent donors. This article reports an extremely rare case of a breast cancer metastasis in a lung metastasis of clear cell type renal cell carcinoma that met all Campbell and coworkers’ tumor-to-tumor metastasis criteria. Additionally, we present the literature case reports of breast cancer metastasis in renal cell carcinomas and try to discuss the mechanisms underlying its occurrence. Since this phenomenon identification will impact the therapeutic strategy and it is not easily detected by image, the anatomopathological study of any and all suspicious lesions is of crucial importance. To the best of our knowledge, this is the first report of a metastasis inside a metastasis.

Tumor to Tumor Metastasis: A Case Report

Colon carcinoma spreads locally around the intestine wall and can undergo distant metastasis via the hematogenous or lymphatic spread. It rarely metastasizes to the female genital tract and is not fully reported to involve a uterine leiomyoma. Herein we report such an unusual case of a 27 years female a known case of sigmoid colon adenocarcinoma who presented with abdominal pain with bilateral adnexal mass and per vaginal bleeding. Exploratory laparotomy with bilateral resection of ovaries with subsequent polypectomy was done, which on histopathology, it revealed metastatic adenocarcinoma in bilateral ovaries and submucosal leiomyoma. Hence, a lesion with dimorphic histomorphology should be carefully evaluated to rule out the possibility of malignant-to-benign tumor-to-tumor metastasis.

Rare Presentation of Metastatic Lobular Breast Carcinoma Involving Clear Cell Renal Cell Carcinoma

Although the first case of tumor-to-tumor metastasis was reported over a century ago, it remains a rare occurrence. We report a rare case of metastatic infiltrating lobular carcinoma involving clear cell renal cell carcinoma, as well as offer a brief literature review.

Tumor-To-tumor Metastasis: Prostatic Cancer Metastasizing to Malignant Solitary Fibrous Tumor of The Lung

Background: Tumor-to-tumor metastasis is an extremely rare but interesting phenomenon. Prostatic cancer metastasizing to malignant solitary fibrous tumor (SFT) of the lung has not been previously reported.Case Presentation: In this report, we describe the case of a 60-year-old man presenting a large solitary neoplasm in the left lung on computed tomography. Pathology after left lung wedge resection indicated two different cancerous cell components: SFT cells with malignant potential and prostatic cancer cells. The heterogeneous cells of prostatic origin were confirmed by using evidence from fine needle aspiration and pathology after radical prostatectomy.Conclusions: We report the first tumor-to-tumor metastasis of prostatic cancer to lung malignant SFT.