{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,21]],"date-time":"2026-10-21T21:44:13Z","timestamp":1792619053529,"version":"4.5.0"},"reference-count":8,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T00:00:00Z","timestamp":1778544000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Oncol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Sarcomatoid urothelial carcinoma (SUC) is a rare, highly aggressive subtype of urothelial carcinoma (UC) accounting for fewer than 1%\u20132% of all urothelial malignancies. It is characterized by biphasic histology, a dismal prognosis, resistance to conventional chemotherapy, and a propensity for distant metastasis. Clinically confirmed cardiac metastasis from UC is exceedingly rare, with only sporadic cases documented worldwide.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Case summary<\/jats:title>\n                    <jats:p>\n                      We report a 55-year-old woman who presented with right-sided flank pain and gross hematuria. Percutaneous renal biopsy confirmed right renal pelvis SUC with approximately 85% sarcomatoid component. The patient underwent palliative robot-assisted laparoscopic nephroureterectomy; final pathological staging was pT3N1M1 (Stage IV). Approximately two months postoperatively, imaging confirmed multifocal metastases involving the lungs, pleura, liver, and lymph nodes, and first-line chemo-immunotherapy was initiated with gemcitabine plus carboplatin plus nivolumab. Carboplatin was substituted for cisplatin because the patient was deemed cisplatin-ineligible owing to renal insufficiency, following a modified CheckMate 901 framework. After one cycle, grade IV myelosuppression (platelet nadir 28 \u00d7 10\n                      <jats:sup>9<\/jats:sup>\n                      \/L) necessitated permanent discontinuation of cytotoxic agents. During myelosuppression recovery, the patient developed palpitations; echocardiography revealed a large, broad-based right ventricular (RV) mass (50 \u00d7 41\u00a0mm). Treatment was revised to tislelizumab monotherapy (200 mg, every three weeks [q3w]). Serial echocardiographic follow-up documented progressive RV mass regression from 50 \u00d7 41\u00a0mm to 22 \u00d7 32\u00a0mm and ultimately to 11 \u00d7 14\u00a0mm, with stable systemic disease throughout.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>To our knowledge, this is the first documented case of isolated RV metastasis from right renal pelvis SUC achieving an objective response to anti-PD-1 immunotherapy. The sustained imaging regression under tislelizumab monotherapy strongly suggests\u2014but does not definitively confirm\u2014a metastatic etiology. For patients with high PD-L1\u2013expressing SUC and cardiac metastasis who are intolerant of combined chemo-immunotherapy regimens, immune checkpoint inhibitor monotherapy may represent a feasible and well-tolerated treatment strategy.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.3389\/fonc.2026.1763282","type":"journal-article","created":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T11:03:08Z","timestamp":1778583788000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":1,"title":["Case Report: Cardiac metastasis of sarcomatoid urothelial carcinoma"],"prefix":"10.3389","volume":"16","author":[{"given":"Nan","family":"Ma","sequence":"first","affiliation":[{"name":"Department of Cardiology (Ward 1), Gansu Provincial People\u2019s Hospital","place":["Lanzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jing","family":"Wang","sequence":"additional","affiliation":[{"name":"Department of Ultrasound Medicine, Gansu Provincial People\u2019s Hospital","place":["Lanzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Miaomiao","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Pathology, Gansu Provincial Cancer Hospital","place":["Lanzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Liping","family":"Yang","sequence":"additional","affiliation":[{"name":"Research Ward, Gansu Provincial People\u2019s Hospital","place":["Lanzhou, China"]}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1965","published-online":{"date-parts":[[2026,5,12]]},"reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1016\/j.ijscr.2025.111514","article-title":"Multiple cardiac complications due to sepsis and cardiac metastasis of a sarcomatoid urothelial cell carcinoma of the urinary bladder: a case report","volume":"133","author":"Pouwels","year":"2025","journal-title":"Int J Surg Case Rep"},{"key":"B2","doi-asserted-by":"publisher","first-page":"28","DOI":"10.1186\/s43044-022-00264-y","article-title":"Multiple cardiac metastases from urothelial carcinoma: a case report","volume":"74","author":"Grech","year":"2022","journal-title":"Egypt Heart J"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.3389\/fonc.2019.00738","article-title":"Renal cell carcinoma metastasizing to the left atrium with coronary sinus invasion: a rare site of metastasis mimicking myxoma","volume":"9","author":"Nkengurutse","year":"2019","journal-title":"Front Oncol"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1097\/PAS.0b013e3182159dec","article-title":"Sarcomatoid carcinoma of the urinary bladder: the final common pathway of urothelial carcinoma dedifferentiation","volume":"35","author":"Cheng","year":"2011","journal-title":"Am J Surg Pathol"},{"key":"B5","article-title":"High PD-L1 expression and postoperative immunotherapy in upper tract urothelial carcinoma with sarcomatoid differentiation: a case series","volume-title":"Preprint: Research Square","author":"Ma","year":"2026"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1002\/cjp2.70021","article-title":"Sarcomatoid areas of urothelial carcinoma are enriched for CD163-positive antigen-presenting cells","volume":"11","author":"Johnson","year":"2025","journal-title":"J Pathol Clin Res"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1016\/j.annonc.2024.03.001","article-title":"ESMO Clinical Practice Guideline interim update on first-line therapy in advanced urothelial carcinoma","volume":"35","author":"van der Heijden","year":"2024","journal-title":"Ann Oncol"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1111\/cas.14681","article-title":"Tislelizumab in Asian patients with previously treated locally advanced or metastatic urothelial carcinoma","volume":"112","author":"Ye","year":"2021","journal-title":"Cancer Sci"}],"container-title":["Frontiers in Oncology"],"original-title":[],"link":[{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1763282\/full","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,5,12]],"date-time":"2026-05-12T11:03:11Z","timestamp":1778583791000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.frontiersin.org\/articles\/10.3389\/fonc.2026.1763282\/full"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2026,5,12]]},"references-count":8,"alternative-id":["10.3389\/fonc.2026.1763282"],"URL":"https:\/\/doi.org\/10.3389\/fonc.2026.1763282","relation":{},"ISSN":["2234-943X"],"issn-type":[{"value":"2234-943X","type":"electronic"}],"subject":[],"published":{"date-parts":[[2026,5,12]]},"article-number":"1763282"}}