Focal therapy for renal cell carcinoma is a precision treatment technique that directly targets and destroys cancerous lesions while preserving the maximum amount of surrounding healthy kidney tissue through localized intervention. It is primarily indicated for early-stage renal cell carcinoma in patients with tumors ≤4 cm in diameter (T 1a), particularly for those at higher surgical risk. Compared to traditional radical nephrectomy and partial nephrectomy, focal therapy offers several advantages, including lower physical demands on the patient, minimally invasive nature, reduced risk of complications, and faster recovery. The focal therapy techniques currently utilized in clinical practice include cryoablation, radiofrequency ablation, microwave ablation, irreversible electroporation, high-intensity focused ultrasound, and stereotactic body radiotherapy. This article reviews the principles of various focal therapy techniques, patient selection, and the oncological outcomes, complications, and renal function preservation associated with these focal therapies.

Objective:To compare the therapeutic effects of partial nephrectomy (PN) and cryoablation (CA) in patients with stage cT 1N 0M 0 renal cell carcinoma (RCC). Methods:A retrospective analysis was conducted on clinical data of patients with stage cT 1N 0M 0 RCC who underwent CA and PN treatment at The First Affiliated Hospital of Naval Medical University and Shanghai Ninth People's Hospital between March 2011 and December 2019. There were 50 cases in the CA group (36 from The First Affiliated Hospital of Naval Medical University and 14 from the Shanghai Ninth People's Hospital), and 1 323 cases in the PN group (all from The First Affiliated Hospital of Naval Medical University). PN included open surgery, laparoscopic surgery, or robotic surgery performed under general anesthesia through the abdominal or retroperitoneal approach. CA included laparoscopic surgery under general anesthesia and percutaneous treatment guided by CT or ultrasound under local anesthesia. Propensity score matching was performed based on baseline data of the patients to obtain balanced samples between the two groups using a 1∶2 nearest-neighbor matching method. After matching, comparisons were made between the two groups in terms of perioperative conditions, overall survival (OS), and recurrence-free survival (RFS). Results:After PSM, patient distributions were closely balanced in baseline data such as gender (male/female: 28/19 cases in CA group and 58/36 cases in PN group), age [66.0(53.0, 75.0) years vs. 59.5(50.0, 69.3) years], body mass index[ (24.1 ± 6.4) kg/m 2 vs. (24.1 ± 3.1) kg/m 2], Charlson comorbidity index [1(0, 2) vs. 1(0, 2)], history of malignant tumors [19.1% (9/47) vs. 17.0% (16/94)], preoperative estimated glomerular filtration rate (eGFR) [85.2(65.5, 97.1) ml/(min·1.73m 2) vs. 87.0(73.4, 100.4) ml/(min·1.73m 2)], and R. E.N.A.L. score [6(5, 7) vs. 7(6, 8)] between CA(n=47) and PN(n=94) group. There were significant differences in operative time [97.5(81.2, 117.5) min vs. 145.0(110.2, 185.0) min, P<0.001], estimated blood loss [85.0(50.0, 100.0) ml vs. 100.0(75.0, 200.0)ml, P=0.021], length of hospital stay [3.0(2.0, 4.0) days vs. 7.6(5.0, 9.0) days, P<0.001] between the CA and the PN group. No significant differences were observed in the incidence of postoperative complications [4.3% (2/47) vs. 5.3% (5/94), P=0.784], the eGFR within one week after surgery [83.7(65.6, 106.6) ml/(min·1.73m 2) vs. 83.2(66.7, 97.7) ml/(min·1.73m 2), P=0.645], the median follow-up time [ 93 (67, 126) months vs. 85 (68, 139) months, P=0.955], the RFS rate[81.8% vs. 96.8%, P=0.074], or the OS rate [85.7% vs. 97.8%, P=0.190] between the CA and the PN group. Conclusions:For patients with cT 1N 0M 0 stage RCC, CA and PN demonstrate comparable oncologic treatment efficacy, while CA offering the advantages of shorter surgical time, shorter hospital stay, and less blood loss.

Objective:To investigate the safety and prognosis of partial nephrectomy (PN) in the treatment of highly malignant non-clear renal cell carcinoma (nccRCC).Methods:Clinical data of 47 patients with cT 1N 0M 0 high malignant nccRCC treated in Changhai Hospital from March 2016 to March 2022 were retrospectively analyzed. All patients received PN. There were 34(72.3%) males and 13(27.7%) females. The mean age was (53.5±15.0) years, and average BMI, was(23.7±3.4)kg/m 2.The maximum tumor diameter was (29.8±12.6) mm, and R. E.N.A.L. score was 7(5-9), with 37(78.7%) cases of T 1a and 10(21.3%) cases of T 1b. The mean estimated glomerular filtration rate (eGFR) before surgery was (96.3±25.5) ml/ (min·1.73m 2). All patients underwent PN, including 1 patient (2.1%) undergoing open surgery, 29 patients (61.7%) undergoing laparoscopic surgery, and 17 patients (36.2%) undergoing robotic surgery. There were a total of 22(46.8%) cases of papillary cell carcinoma(pRCC)type Ⅱ, 4(8.5%) cases of collecting duct carcinoma (cdRCC), 9(19.1%) cases of MiT family translocated renal cell carcinoma (tRCC), 5(10.6%) cases of mucoid tubular and spindle cell carcinoma (mtSCC)and 7(14.9%) cases of unclassified renal cell carcinoma (uRCC). The surgical conversion rate, positive margin rate, operative time, intraoperative blood loss, complications, and postoperative hospital stay were analyzed. Preoperative and postoperative eGFR were analyzed, and overall survival (OS) and cancer specific survival (CSS) were calculated. Results:All the operations were successfully completed. No radical operation or open operation was performed, with operation time of(100±60) min and intraoperative blood loss of(100±59) ml. There were no intraoperative complication and 1 case (2.1%) suffered from postoperative complication. Postoperative hospital stay were 5 (4-6) days. The mean eGFR after surgery was (86.5±27.1) ml/(min·1.73m 2), and the difference was statistically significant ( P=0.041). In this study, the mean follow-up time was (45.7±20.9)months, and no adjuvant therapy was used after surgery. During the follow-up period, 2 patients died, who all of them were kidney cancer-related death, and both OS and CSS were 95.7% (45/47). Conclusions:PN is safe, feasible and has a good prognosis in the treatment of high malignant T 1 nccRCC. For tumors with clear imaging boundaries and complete envelope, complete tumor resection is more likely, postoperative follow-up should be strict, and no remedial radical or systemic treatment was required.