Ultrasound features of chromophobe renal cell carcinoma metastasized to ovary

A 72-year-old woman was referred to our center because of an incidental finding of an ovarian mass. She had a previous partial right nephrectomy due to renal cell carcinoma (RCC) diagnosed 5 years earlier. Transvaginal ultrasound examination showed a right ovarian solid mass of 40 × 33 × 33 mm in size, with two papillary projections (maximum diameter of the largest papillary projection was 10 mm), and a left ovarian unilocular-solid mass of 39 × 24 × 33 mm in size, with anechoic content and two papillary projections (maximum diameter of the largest papillary projection was 22 mm) (Figure 1a,b). On color Doppler examination, moderate vascularization (color score, 3) was detected in both tumors (Figure 1c,d). The left mass was fixed to the uterus during dynamic examination. A solid mass measuring 14 × 14 × 12 mm was also observed in the vesicouterine pouch (Figure 2). Neither free fluid in the pouch of Douglas nor ascites was detected on either transvaginal or transabdominal examination. Tumor biomarkers were within normal limits (CA125, 39 U/mL; CA15-3, 20.8 U/mL; CA19-9, 19 U/mL; CEA, 3.27 ng/mL; AFP, 4.69 ng/mL). The ultrasound examiner was uncertain about the diagnosis; the first hypothesis was a metastatic tumor, based on the woman's medical history, bilaterality of the tumor and negative CA1251. However, a primary ovarian carcinoma could not be excluded2. Open laparoscopy revealed abdominal carcinomatosis, bilateral adnexal masses and a nodule in the vesicouterine pouch infiltrating the urinary bladder. Left salpingo-oophorectomy and multiple biopsy were performed. Ovarian metastases from chromophobe RCC and positive peritoneal biopsy were diagnosed on histology. After surgery, the patient underwent systemic chemotherapy. Ovarian metastases from carcinoma of the kidney are very rare3. A literature search revealed six reported cases describing the ultrasound appearance of this pathology (Table S1), but only one of these studies described the adnexal mass using International Ovarian Tumor Analysis (IOTA) terminology4. Similar to our study, previous studies described the ovarian metastases from RCC as solid or solid-cystic masses (Table S1), but none of them described the papillary projections in the masses, as was reported in our case. It should be borne in mind that the present primary tumor was a chromophobe RCC, whereas, in previously reported cases, the histology was papillary RCC or clear RCC. In conclusion, we have described ultrasound characteristics of ovarian metastases from a chromophobe RCC. The typical ultrasound appearance is a small bilateral unilocular-solid or solid mass with papillary projections and moderate vascularization on color Doppler (color score, 3). The possibility to discriminate preoperatively between tumors metastasized to the ovary and primary ovarian cancers is fundamental for optimization of patient management. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.