Renal cell carcinoma T staging: Diagnostic accuracy of preoperative contrast-enhanced computed tomography

Renal cell carcinoma (RCC) accounts for 1-2% of all malignancies and is the most common renal tumor in adults. Imaging studies are used for diagnosis and staging. Tumor-Node-Metastasis staging strongly affects prognosis and management, while contrast-enhanced computed tomography (CECT) is regarded as a standard imaging technique for local and distant staging. The present study aimed to evaluate the accuracy of CECT for the preoperative staging of RCC by using surgical and pathological staging as the reference methods. This single-center prospective study was conducted between October 2019 and November 2021. The preoperative abdominal CT scans of patients suspected of having RCC were reviewed. Imaging data were collected, including tumor side and size, and perinephric fat invasion. Intraoperative notes were recorded, including the operation type, perinephric fat invasion, renal vein (RV) or inferior vena cava (IVC) tumor extension, and surrounding organ invasion. pathological data were collected on tumor size, RCC type, presence of clear margins, presence of renal capsule or perinephric fat invasion, renal sinus or pelvicalyceal system (PCS) invasion, segmental or main RV extension, and the involvement of Gerota's fascia and nearby organs. Preoperative CECT revealed that 42 out of 59 tumors had a greater maximum diameter than the pathological specimen, with an overall disparity of 0.25 cm. The specificity of CT for the detection of tumor invasion of the perinephric and renal sinus fat and PCS was 95%, and the sensitivity ranged from 80 to 88%. CT had an 83% sensitivity and a 95 specificity in detecting T4 stage cancer, with a 100% specificity for adrenal invasion. The concordance between radiographic and histological results for RV and IVC involvement was high, with specificities of 94 and 98%, and sensitivities of 80 and 100%, respectively. Overall accuracy for correct T staging was 80%. In conclusion, CECT is accurate in the local T staging of RCC, with high sensitivity and specificity for estimating tumor size and detecting extension to nearby structures and venous invasion.

Prognostic Evaluation of the Site of Invasion in Pathological Stage T3a Renal Cell Carcinoma

BACKGROUND/AIM

To investigate the prognostic values of fat invasion (FI) and renal vein invasion (RVI) in pT3a renal cell carcinoma (RCC), as single factors or concomitant presence.

PATIENTS AND METHODS

We retrospectively reviewed the data of 173 patients who underwent radical or partial nephrectomy for RCC in our Institution.

RESULTS

At a median follow-up time of 48 months, patients with RVI showed significantly increased risk of disease recurrence and worse cancer-specific survival (CSS) when compared to those with FI (p=0.007, p=0.022, respectively). Having combined RVI and FI did not show inferior prognosis compared to those with RVI only. In multivariable analysis, RVI was an independent factor for disease recurrence (HR=2.06, 95% CI=1.10-3.87, p=0.024) and CSS (HR=2.46, 95% CI=1.01-6.0, p=0.048).

CONCLUSION

For patients with T3a renal tumors, RVI was associated with inferior prognosis compared to those with FI.

[LEIOMYOSARCOMA OF THE OVARIAN VEIN WITH THE RENAL VEIN INVASION: A CASE REPORT]

A 56-year-old woman had complained of two year's consecutive left-side abdominal pain. Retroperitoneal tumor was diagnosed and the patient was referred to our institute in December 2014. Laboratory data including endocrinological activity and serological markers were within the normal ranges. Imaging studies showed that the solid tumor measuring 5 cm in diameter was uncovered in the retroperitoneum, between the abdominal aorta and left kidney. The patient underwent surgical removal of the tumor with the left kidney because the mass was highly adhesive to the left ovarian vessels and left renal vein. Histological examination showed proliferating spindle cells in the tumor, and immunoreactivity for desmin and alfa-smooth muscle actin in tumor cells confirmed the diagnosis of leiomyosarcoma originated in left ovarian vein with left renal vein invasion. The patient has been free of disease 21 months after the surgery. Ovarian vein leiomyosarcoma is extremely rare and we have found 18 cases in literature. Furthermore, only three cases of leiomyosarcoma arising from the ovarian vein with the renal vein invasion were reported including our case.

Tumor size and Fuhrman grade further enhance the prognostic impact of perinephric fat invasion and renal vein extension in T3a staging of renal cell carcinoma

OBJECTIVE

To evaluate the prognostic values of perinephric fat invasion and renal vein invasion in pT3a renal cell carcinoma, as stand-alone factors and in combination with tumor size and Fuhrman grade.

METHODS

Survival data of pT1 and pT2 renal cell carcinomas were analyzed alongside pT3a tumors of similar size bands (pT1 vs pT3a <7 cm, pT2 vs pT3a >7 cm). Patients with adjuvant therapy, positive surgical margins, metastasis or pT3b-pT4 tumors were excluded.

RESULTS

No significant baseline demographic differences existed between the groups. Patients with renal vein invasion had larger tumors (median, 7.2 ± 3.0 cm vs 5.5 ± 3.6 cm, P = 0.039), and were more symptomatic (90.0% vs 61.7%, P = 0.028) compared with patients with perinephric fat invasion alone. Patients with perinephric fat invasion alone appeared to have better disease-free survival compared with those with renal vein invasion (P = 0.009). Having both perinephric fat invasion and renal vein invasion did not result in a poorer disease-free survival. pT3a (perinephric fat invasion) tumors <4 cm and 4-7 cm have significantly worse disease-free survival compared with pT1a and pT1b tumors (P < 0.001). Similarly, pT3a (perinephric fat invasion) tumors measuring ≥7 show a trend of poorer disease-free survival compared with pT2a and pT2b tumors (P = 0.267). Disease-free survival correlated with Fuhrman grading for patients with perinephric fat invasion (P = 0.008). In multivariate analysis, the survival curve of pT3a perinephric fat invasion group closely approximates that of pT2 group, whereas survival of the renal vein invasion group was significantly worse than the pT2 and perinephric fat invasion groups (P = 0.001).

CONCLUSION

pT3a tumors with perinephric fat invasion appear to have better prognosis than those with renal vein invasion. Further stratification of pT3a renal cell carcinomas with regard to tumor size and Fuhrman grade further enhances the prognostic value in this group.