It is not uncommon for RCC to enter the renal vein and IVC, sometimes up to the right atrium, i.e. with the direction of blood flow. Occasionally it can cross over to the contralateral renal vein. Rarely it may enter other veins including in this case the left ovarian vein from the left renal vein with growth down (i.e. retrograde to flow) to the left adnexa.