Renal cell carcinoma (RCC) can invade through the renal vein into the inferior vena cava (IVC), forming a tumor-thrombus in 4–10% of patients [
1,
2]. Right atrial (RA) involvement is rare, occurring in only 1% of cases [
3], and can obstruct RA filling, leading to venous congestion and tricuspid valve dysfunction. Four years ago, this 68-year-old patient was diagnosed with a large tumor mass extending into the RA during a work-up for RCC. Initial transthoracic echocardiography (TTE) showed the mass originating from the IVC, extending up to 5.5 cm into the RA, reaching up to the tricuspid valve (Fig.
1A, B). Distinction between tumor mass and adjacent thrombus was not possible. The patient was anticoagulated and follow-up TTE four weeks later showed mass regression (Fig.
1C). In further course the patient received various chemotherapeutic and immunomodulatory treatments. Recently, he was admitted with progressive dyspnea and started on further chemotherapy for metastatic RCC. Echocardiography showed a 1.5 × 2.4 cm tumor-thrombus with intravascular growth from the IVC extending into the RA with preserved, slightly restrictive blood flow of the RA in Color-Doppler imaging without signs of venous congestion (Fig.
1D, E,G). Additionally, a large, septated pleural effusion with partial atelectasis of the left lung was diagnosed as malignant effusion (Fig.
1F). This case is intriguing as it shows a stable course of the tumor-thrombus over four years despite initially advanced disease. …
