Real-Time Contrast-Enhanced Ultrasound Combined with Ultrasound Monitoring Radiofrequency Ablation Versus Laparoscopic Partial Nephrectomy for cT1a Renal Cell Carcinoma: A Comparative Study with Mid-Term Follow-Up

doi:10.21203/rs.3.rs-3915666/v1

Objective

The study aims to compare oncological and functional mid-term outcomes following real-time contrast-enhanced ultrasound combined with ultrasound monitoring radiofrequency ablation (CEUS/USM-RFA) versus laparoscopic partial nephrectomy (LPN) for treating cT1a renal cell carcinoma (RCC).

Methods

This is a retrospective data analysis of a high-volume single tertiary center. Patients with cT1a RCC were treated with CEUS/USM-RFA or LPN following multidisciplinary decision-making. According to different surgical methods, patients were divided into the RFA and LPN groups. Demographic information, tumor characteristics, surgical data, complications, and functional and oncological outcomes were reviewed. Differences between categorical and continuous parameters were evaluated using Pearson's chi-square and Student's t-tests, respectively.

Results

According to different surgical methods, 164 patients were divided into the RFA (41 cases) and LPN (123 cases) groups. The results revealed a nonsignificant difference in gender, tumor side, tumor size, RCC type, R.E.N.A.L. score, major complications, technical success, technique efficacy, or local tumor progression (LTP) between the two groups (p > 0.05). However, significant differences were observed in age, Eastern Cooperative Oncology Group (ECOG) score, Charlson Comorbidity Index (CCI) score, American Society of Anesthesiologist (ASA) score, tumor location, and minor complications (p < 0.05). The operative time, estimated blood loss, hospitalization time, and estimated glomerular filtration rate (eGFR) loss of the affected kidney in the RFA group were less than in the LPN group (p < 0.05). The decline of post-procedure eGFR of the affected kidney at six months was significantly less in RFA than in the LPN group (1.39 ± 4.67 vs. 4.32 ± 4.00 mL/min/1.73 m², p < 0.001). Nevertheless, both groups had a similar 2-year recurrence-free survival (RFS) rate (97.65% vs. 100%, p = 0.083).

Conclusion

The CEUS/USM-RFA and LPN for cT1a RCC were all safe and effective. In rigorously screened patients with cT1a RCC, CEUS/USM-RFA had comparable oncological outcomes with LPN. The CEUS/USM-RFA had superiority in perioperative outcomes and preserving renal function.

Health sciences/Oncology

Health sciences/Urology

Recently, the advent and popularization of ultrasound (US) and other medical imaging technologies have recently increased the number of renal cell carcinoma (RCC) patients diagnosed at an early stage, with the majority exhibiting cT1a stage RCC^1,2. Meanwhile, partial nephrectomy (open, laparoscopic, or robotic-assisted surgery) remains the standard cT1a RCC treatment ³. Minimally invasive treatments, such as radiofrequency ablation, have received a growing interest. Quite recently, professional organizations, including the American Urological Association, European Association of Urology, Chinese Urological Association, and the National Comprehensive Cancer Network, have updated the RCC guidelines, recommending radiofrequency ablation (RFA) as a surgery alternative for cT1a RCC in elderly, renal insufficiency, comorbid patients considered unfit for surgery, those with a genetic predisposition to develop multiple tumors with recurrences after previous surgery, patients with bilateral tumors or a solitary kidney, and those at high risk of complete loss of renal function following partial nephrectomy (PN) ^3–6. Meanwhile, RFA and PN have comparable metastatic-free and disease-free survival rates, and ablation has higher local recurrence rates ^7–9.

Traditionally, computed tomography (CT) alone or combined with ultrasound (US) has been used for initial pre-ablation evaluation. These techniques are also employed to guide the probe placement, evaluate the ablation zone, and assess tumor post-ablation ^10,11. Additionally, the US can be used as a standalone method for real-time imaging, as it is inexpensive, convenient, and does not involve radiation exposure or nephrotoxicity ^11–13. However, both techniques have certain limitations. The CT may have relatively high radiation exposures, lack live imaging capability, and have contrast-related issues, including renal insufficiency. Nonetheless, the US may have reduced visualization and accuracy ^11,12,14. Real-time contrast-enhanced ultrasound (CEUS) enables dynamic observation of tumor microfluidic perfusion, enhancing tumor targeting and visualization ^15–17. It clearly displays the boundaries between the tumor and normal renal parenchyma, providing accurate guidance for ablation electrode placement in the target tumor ^11,18,19. The CEUS allows for quick and effective assessment of radiofrequency ablation (RFA) efficacy during the operation ^11,20. Moreover, it efficiently identifies residual tumor tissues and enhances simultaneous RFA supplementation ^2,11,17,20. The US contrast agents exhibit no nephrotoxicity while having minimal adverse reaction rates, rendering them a safe option in compromised or protected renal function, such as in renal transplant recipients and individuals with a previous history of serious allergic reaction to CT or MRI contrast agents ^16,18. Nevertheless, there is currently no comparative study between the real-time contrast-enhanced ultrasound combined with ultrasound monitoring radiofrequency ablation (CEUS/USM-RFA) and LPN for treating cT1a RCC. This study aimed to evaluate oncologic and functional outcomes for CEUS/USM-RFA versus LPN for cT1a RCC, enabling patients to decide on suitable surgery.

This research is a single-center retrospective study that was performed in the First Affiliated Hospital of Xinxiang Medical University (Weihui, China). All methods were approved by the First Affiliated Hospital of Xinxiang Medical University Institutional Review Board (EC-023-087). The study has been carried out in accordance with the Declaration of Helsinki. Written informed consent was obtained from all participants to participate and publish the identifiable images.

2.1 Patient population

This retrospective study obtained the results and the clinical records for patients who underwent CEUS/USM-RFA (RFA group) or LPN (LPN group) for cT1 RCC from August 2017 to June 2021 in the First Affiliated Hospital of Xinxiang Medical University. Inclusion criteria encompassed individuals with solitary, histology-confirmed RCC at stage cT1N0M0. Patients with a history of prior, multiple, bilateral, metastatic, or hereditary RCC were excluded. The multidisciplinary tumor board, including a urologist, an ultrasound intervention physician, and an anesthesiologist, decided on CEUS/USM-RFA. The decision to undergo LPN was at the discretion of the patient and the treating urologist.

2.2 Treatment techniques

2.2.1 CEUS/USM-RFA

Pre-procedural US evaluation was performed to determine the suitability of the patient for RFA of the mass and strategize the optimal puncture site and needle trajectory. The CEUS/USM-RFA techniques had been previously described ^{11, 17}. Specifically, after general anesthesia, CEUS/US imaging was performed with dual frame real-time harmonic ultrasonographic imaging using the microbubble contrast agent SonoVue under a low mechanical index to evaluate the tumor size, boundary, and vascular supply (Fig. 1A). A US-guided core-needle biopsy of the mass was performed in the case of a histologic evaluation has not already been performed. The RFA needle was positioned within the mass using US guidance. Single overlapping RFA or multiple electrode RFA depends on the tumor size or shape. Generally, tumors of 2.5 cm or smaller were treated with one antenna, tumors of 2.5–3.5 cm were treated with two antennas, and tumors of at least 3.5 cm were treated with three antennas. When necessary, the hydrodissection technique was used to protect nearby critical structures. The US was utilized for continuous real-time monitoring of the ablation zone, with the ablation margins extending beyond a 5 mm margin of the tumor (Figs. 1B–C). After 5–10 min post-ablation, a repeated US/CEUS was performed to determine whether any residual tumor was present (Fig. 1D). If present, the ablation needle was repositioned, and a repeated ablation was performed. After the tumor had been completely ablated, the needle track was ablated to avoid bleeding and tumor seeding.

2.2.2 LPN

The LPN techniques (transperitoneal or retroperitoneal approach) had been previously described ^21–23. Briefly, during the hilar vascular control stage of laparoscopic partial nephrectomy (LPN), mannitol was administered, and the renal artery was clamped. The kidney mass was dissected using cold scissors, maintaining a safety 5 mm margin. After resecting the tumor, the tumor envelope integrity was confirmed, followed by careful suturing of the calyx, bleeders, and tumor bed.

2.3 Data collection and follow-up

The last follow-up was collected up to June 2023. Before the procedure, all patients had either contrast-enhanced CT (CECT) or contrast-enhanced MRI (CEMRI). The recorded variables included the following: patient age, gender, tumor size, tumor location, Charlson Comorbidity Index (CCI) score, Eastern Cooperative Oncology Group (ECOG) score, American Society of Anesthesiologist (ASA) score, RCC type, R.E.N.A.L. score, operative time, estimated blood loss (EBL), postoperative stay, complications, estimated glomerular filtration rate (eGFR) loss. The blood loss assessment was conducted based on decreased serum hemoglobin (Hb) concentrations, measured pre-operatively and 24 h postoperatively. Renal ultrasound was performed on the third postoperative day to evaluate for perinephric hematoma. The eGFR loss was calculated as the difference between the preoperative and postoperative six-month eGFR values of the injured kidney.

Furthermore, the follow-up CECT or CEMRI was performed 3, 6, 12, and 24 months after surgery to monitor the postoperative progress and evaluate any potential recurrence or metastasis. Technical success, technique efficacy, local tumor progression (LTP), and recurrence-free survival (RFS) rate were calculated. Technical success was respectively defined as the presence of a negative histological margin in the LPN group and the complete disappearance of the tumor, as demonstrated by intraoperative CEUS in the RFA group. Technique efficacy and LTP were defined by established criteria ²⁴.

2.4 Statistical analysis

Statistical analyses were performed using SPSS 23.0. Descriptive statistics are presented as the mean ± SD, median, and range or percentage. Demographic and clinical characteristics were analyzed using Student's t-tests for continuous variables and the chi-square test for categorical variables. All statistical tests were 2-sided, and p < 0.05 was considered significant. Kaplan-Meier analysis was used to calculate and compare 2-year RFS rates.

3.1 Patients and tumors characteristics

Finally, of the 164 cases that were identified to fulfill the inclusion criteria, 41 underwent RFA, and 123 underwent LPN for T1 RCC (Patient flowchart; Figure 2). Patients treated with LPN were significantly younger (p < 0.001) and had lower CCI, ECOG, and ASA scores (p < 0.001) compared with patients treated with RFA. The baseline renal function was significantly poorer (p < 0.001) in the RFA group (38.22 ± 5.01 mL/min/1.73 m²) than in the LPN group (42.83 ± 5.21 mL/min/1.73 m²). The results elucidated nonsignificant differences in gender between the two groups (p = 0.508). Table 1 summarizes the characteristics of patients.

The RFA group comprised a higher tumor proportion in the central, dorsal, middle, and lower poles (p < 0.001) than the LPN group. Figure 3 depicts an endophytic RCC case treated with RFA and follow-up images after two years. The mean tumor size was 3.14 and 3.27 cm for patients treated with LPN and RFA, respectively (p = 0.063). The findings indicated a nonsignificant difference in laterality (p = 0.786), RCC type (p = 0.808), or R.E.N.A.L score (p = 0.087) based on the surgical approach. Table 1 lists the tumor characteristics.

3.2 Procedure outcomes

Table 2 shows the procedure outcomes of the two groups. The mean operative time was 82.90 ± 18.76 and 138.37 ± 10.27 min for RFA and LPN, respectively (p < 0.001). The mean postoperative stay was 3.51 ± 0.60 and 6.67 ± 0.54 days for RFA and LPN, respectively (p < 0.001). Estimated blood loss was significantly higher in the LPN group (p < 0.001) than in the RFA group. The eGFR of postoperative injured kidneys (p = 0.088) exhibited a nonsignificant difference between the two groups. Midterm post-procedure eGFR loss decline at six months was significantly less in the RFA (1.39 ± 4.67 vs. 4.32 ± 4.00 mL/min/1.73 m²) than in the LPN (p < 0.001). Figure 4 illustrates pre- and postoperative renal function in the two groups.

3.3 Postoperative complications

Table 3 outlines the procedure-related complications calculated using the Clavien complications score between the two groups. Clavien complication grading the system indicated a significantly higher minor complication rate in the LPN group than in the RFA group. Nevertheless, there existed a nonsignificant distinction in severe complications between the two groups. One patient (0.81%) suffered major bleeding (Clavien III) after LPN, underwent laparoscopic renorrhaphy to control the bleeding, and received a blood transfusion. Finally, the patient was cured and discharged. Three patients (2.44%) developed delirium (Clavien IV) after LPN and were cured after medication under the supervision of neurologists.

3.4 Oncologic efficacy

Both groups achieved treatment success and technical effectiveness (100%) in a single session. In the two-year follow-up of the two groups, LPT was 0% (0/123) and 2.44% (1/41) in the LPN and RFA groups, respectively (p = 0.250). One patient exhibited signs of local recurrence on an enhanced CT scan 21 months following RFA (Figure 5). In response, the patient chose surveillance because the RCC growth rate (mean 3 mm/yr) was slow in most cases, and progression to mRCC was rare (1%–2%) ²⁵. The 2-year RFS rate was 100% and 97.56% in the RPN and RFA groups, respectively (p = 0.083). RFS curves are displayed in Figure 6.

In 1997, Zlotta et al. ²⁶ first used RFA to treat small RCC. The RFA is widely used as an alternative treatment for small RCC due to its advantages of minimal trauma, good efficacy, fast recovery, fewer complications, strong repeatability, low requirements for patient primary conditions, and the ability to be performed under local anesthesia ^4,7,27. However, multiple studies have reported that insufficient intraoperative ablation and the inability to evaluate the ablation effect in real-time by conventional US, CT, or MRI leads to tumor residue and local recurrence after RFA ^28–30. This clinical demand has sparked the development of many new imaging technologies, including CEUS, CECT, and CEMRI, among others, which can assist surgeons in intraoperative margin assessment ^16,20,31. When a residual mass is detected, repeated ablation in the same procedure is organized immediately, significantly increasing the complete ablation rate after the initial treatment ^30–32. Notably, a study comparing CEUS with CECT for guiding the RFA of HCC has found that CEUS provided the overall complete ablation rate, reduced the relapse rate, and increased the survival rate ³³.

Our findings suggest that among the enrolled population, the RFA group included a significant disadvantage in age, preoperative injured kidneys eGFR, Charlson, ECOG, and ASA scores compared to the LPN group (p < 0.05 for all), consistent with RFA applicability for RCC treatment ^3–6. Anterior renal tumors were once considered a relative contraindication for percutaneous ablation, as they pose a risk of damage to adjacent organs, including the small intestine, pancreas, and colon ³⁴. The difficulty of puncture for upper polar tumors is greater and more likely to damage organs such as the pleura, spleen, and liver ^27,35. Additionally, RFA exhibits a higher likelihood of identifying and managing central RCC than LPN ²⁸. Therefore, this study included more cT1a stage RCC in the posterior, middle, lower pole, and central regions in the RFA group.

The RFA can be performed under local anesthesia (LA), conscious sedation (CS), or general anesthesia (GA) ^36,37. All cases in the RFA group underwent anesthesia assessment prior to surgery and received general anesthesia. The putative advantages are as follows: (1) general anesthesia facilitates intraoperative respiratory dynamic regulation of the patient, enforced Valsalva maneuver, and extended apnea, enhancing tumor precision and targeting, particularly in the upper pole region, while concurrently minimizing collateral harm ³⁴; (2) enhanced patient safety and comfort are achieved through dedicated vigilance and hemodynamic and pain management by anesthesiologists ³⁷; (3) studies across multiple series of percutaneous ablation for stage T1a RCC have consistently demonstrated the highest rate of surgical tumor control under general anesthesia ^36,37. Insufficient pain control (e.g., LA) may lead the radiologist to hasten or discontinue the RFA procedures, potentially culminating in an incomplete ablation.

Here, CEUS/USM-RFA displayed significant advantages regarding operative time, blood loss, and postoperative hospital stay for T1a RCC compared with LPN (p < 0.05). These results were consistent with Acosta Ruiz V et al. ³⁸, indicating that RFA significantly reduced the complication rates compared with LPN for T1a RCC. However, the incidence of postoperative minor complications was significantly increased in our study, which can be reasonably explained by the more recorded complication types herein. The RFA group revealed no major complications, mainly because of tumor exclusion in dangerous sites, such as proximal ureters (3). Second, the hydrodissection technique can further increase the distance between the tumor and the non-target organs ^34,39,40. Third, the distance between the kidney and the bowel tends to increase when positioning the patient in a posterior oblique or lateral position ^34,39. Fourth, CEUS improved targeting and visualization of the tumor for needle placement, avoiding damage to neighboring tissues ^11,18. These measures almost always provide enough safety guarantees for RFA. Statistical analysis revealed that the major complications had a nonsignificant difference between the two groups (p = 0.573).

Reportedly, RFA is superior to PN in preserving renal function after treatment ^41–43. Our study found little or no change in eGFR in patients undergoing CEUS/USM-RFA compared to a significant decrease in LPN patients. There are several possible reasons for this result. RFA is performed in non-ischemic conditions, while temporary occlusion of the renal artery during surgery in the LPN group could lead to renal functional decline ⁴⁴. The wedge-shaped incision used to remove the tumor in LPN may result in a higher loss of nephrons compared to removing the tumor with a sphere-shaped ablation zone tailored to the tumor shape and size ⁴³. In addition, the trauma caused by surgery in LPN was greater than that in RFA, which could exacerbate kidney damage ⁹.

Technical success and technique efficacy were achieved for all 164 tumors (100%) through single surgical interventions within both study groups, which aligns with the observations of Parker et al ²⁸. Notably, the technical efficiency of US-induced RFA for T1a RCC treatment was only 75.4%, as reported by Jasinski et al ²⁷. In the RFA group, the high technical success and technique efficacy may be attributable to four reasons. 1) The relatively strict inclusion criteria. All lesions were less than 4 cm, and most were exophytic, located in the middle and lower pole of the kidney. 2) RFA performed under general anesthesia. 3) The single overlapping RFA or multiple electrode RFA used in this study can generate a large enough ablation zone to encompass the entire tumor. 4) The CEUS/US allows for more precise guidance of the puncture and real-time assessment of the ablation effect, which in turn guides the intraoperative supplemental ablation as necessary to minimize tumor retention. The 2-year LTP in the RFA group was 2.44%, agreeing with the 2.35% LTP reported by Zangiacomo et al ⁴⁵. for enhanced CT-guided RFA for stage T1a RCC. Meanwhile, in the LPN group, we did not observe the local progression of the tumor. The LTP revealed a nonsignificant difference between the RFA and LPN groups (p = 0.250), a concordance in line with the outcomes delineated by Thompson et al ⁴⁶. Multiple studies have demonstrated that the oncological outcome with RFA is as good as that with PN ^42,47,48. Nevertheless, this conclusion is controversial ^28,46,49. Herein, the RFA group had a similar RFS to the LPN group, suggesting that CEUS/USM-RFA has comparable oncological outcome to LPN in treating rigorously screened cT1a RCC patients.

Our study had some limitations. First, this was a retrospective study. The likelihood of selection bias cannot be completely excluded. Second, the number of patients was relatively small for CEUS/USM-RFA, which limited our ability to perform propensity score matching. Third, this study did not assess long-term oncological outcomes but only mid-term outcomes. Therefore, randomized, controlled, long-term trials are necessary to compare oncological outcomes adequately following LPN and CEUS/USM-RFA.

The CEUS/USM-RFA and LPN for cT1a RCC were all safe and effective. For rigorously screened cT1a RCC patients, we showed comparable oncologic outcomes for both CEUS/USM-RFA and LPN. Moreover, CEUS/USM-RFA had superiority in perioperative outcomes and preserving renal function, which provides a valuable method for a patient ineligible for partial nephrectomy.

Data availability statement

All data generated or analyzed during this study are included in this article. The datasets used and/or analyzed during the current study are available from the corresponding authors upon reasonable request.

Conflict of Interest

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Author Contributions

SC: Data curation, Methodology, Visualization, Writing – review & editing, Conceptualization, Formal Analysis, Investigation, Writing – original draft. HF: Data curation, Investigation, Writing – review & editing. GS: Data curation, Investigation, Methodology, Validation, Writing – review & editing. FZ: Writing – review & editing, Funding acquisition, Resources, Supervision, Visualization. RL (Ran Li): Resources, Supervision, Visualization, Writing – review & editing. RL (Ranlu Liu): Writing – review & editing, Data curation, Methodology, Project administration, Validation.

Funding

This research received no external funding.

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Table 1. Patients and tumor characteristics.
Variables	RFA (n = 41)	LPN (n = 123)	P-value
Age, median (range)	75 (65–88)	65 (44–78)	< 0.001
Sex, no. (%)			0.508
Male	25 (60.98)	82 (66.67)
Female	16 (39.02)	41 (33.33)
Tumor side, no. (%)			0.786
Left	18 (43.90)	57 (46.34)
Right	23 (56.10)	66 (53.66)
Tumor size (cm), mean (SD)	3.14 (0.42)	3.27 (0.42)	0.063
Preoperative injured kidney eGFR, mean (SD)	38.22 (5.01)	42.83 (5.21)	< 0.001
CCI score, mean (SD)	2.12 (0.31)	1.28 (0.47)	< 0.001
ECOG score, mean (SD)	1.51 (0.60)	0.78 (0.66)	< 0.001
ASA score, no. (%)			< 0.001
I	3 (7.12)	105 (85.37)
II	30 (73.17)	18 (14.63)
III	8 (19.51)	0 (0)
Centrality, no. (%)			0.036
Central	5 (12.20%)	3 (2.44%)
Peripheral	36 (87.80%)	120 (97.56%)
Location relative to polar lines, no. (%)			0.025
Upper polar	4 (9.76%)	38 (30.89%)
Middle polar	21 (51.22%)	51 (41.46%)
Lower polar	16 (39.02%)	34 (27.64%)
Anterior/Posterior, no. (%)			0.002
Anterior	12 (27,27%)	71 (58.66%)
Posterior	29(72.73%)	52 (41.34%)
RCC type, no. (%)			0.808
Clear cell	34 (82.93%)	104 (84.55%)
Papillary	4 (9.76%)	12 (9.76%)
Chromophobe	2 (4.88%)	5 (4.07%)
Eoesinophil	1 (2.44%)	2 (1.63%)
R.E.N.A.L. score, mean (SD)	6.26 (0.90)	6.55 (0.93)	0.087

Table 2. Procedure outcomes.
Variable	Treatment group		p-value
	RFA (n = 41)	LPN (n = 123)
Operative time (min), mean (SD)	82.90 (18.76)	138.37 (10.27)	< 0.001
postoperative stay (day), mean (SD)	3.51 (0.60)	6.67 (0.54)	< 0.001
Estimated blood loss (mL), mean (SD)	75.12 (12.60)	138.32 (19.83)	< 0.001
Postoperative eGFR in the injured kidney (mL/min/1.73 m²), mean (SD)	36.83 (5.52)	38.50 (5.38)	0.088
eGFR loss in the injured kidney (mL/min/1.73 m²), mean (SD)	1.39 (4.67)	4.32 (4.00)	< 0.001
eGFR preservation in injured kidney (%), mean (SD)	96.89 (12.54)	90.16 (9.56)	< 0.001

Table 3. Comparison of postoperative complications between the two groups, n (%).
Variable		Treatment group		p-value
		RFA (n = 41)	LPN (n = 123)
Minor complications (Clavien I and II)		14 (32.56%)	77 (60.60%)	0.001
Major complications (Clavien III and IV)		0 (0%)	4 (3.25%)	0.573
Clavien complication grade
I	Fever	4 (9.76%)	16 (13.01%)
I	Abdomen/back pain	3 (7.32%)	17 (13.82%)
I	Gross hematuria	1 (2.44%)	6 (4.88%)
I	Nausea/vomiting	4 (9.76%)	14 (11.38%)
II	Perinephric hematoma	2 (4.88%)	24 (19.51%)
III	Major bleeding	0 (0%)	1 (0.81%)
IV	Delirium	0 (0%)	3 (2.44%)

No competing interests reported.

Real-Time Contrast-Enhanced Ultrasound Combined with Ultrasound Monitoring Radiofrequency Ablation Versus Laparoscopic Partial Nephrectomy for cT1a Renal Cell Carcinoma: A Comparative Study with Mid-Term Follow-Up

Status:

Version 1

Abstract

Objective

Methods

Results

Conclusion

Figures

1 Introduction

2 Materials and Methods

2.1 Patient population

2.2 Treatment techniques

2.2.1 CEUS/USM-RFA

2.2.2 LPN

2.3 Data collection and follow-up

2.4 Statistical analysis

3 Results

3.1 Patients and tumors characteristics

3.2 Procedure outcomes

3.3 Postoperative complications

3.4 Oncologic efficacy

4. Discussion

5. Conclusions

Declarations

References

Tables

Additional Declarations

Status:

Version 1