Complications of ultrasound-guided percutaneous microwave ablation of renal cell carcinoma

Advances in Image-Guided Ablation Therapies for Solid Tumors

Image-guided solid tumor ablation methods have significantly advanced in their capability to target primary and metastatic tumors. These techniques involve noninvasive or percutaneous insertion of applicators to induce thermal, electrochemical, or mechanical stress on malignant tissue to cause tissue destruction and apoptosis of the tumor margins. Ablation offers substantially lower risks compared to traditional methods. Benefits include shorter recovery periods, reduced bleeding, and greater preservation of organ parenchyma compared to surgical intervention. Due to the reduced morbidity and mortality, image-guided tumor ablation offers new opportunities for treatment in cancer patients who are not candidates for resection. Currently, image-guided ablation techniques are utilized for treating primary and metastatic tumors in various organs with both curative and palliative intent, including the liver, pancreas, kidneys, thyroid, parathyroid, prostate, lung, breast, bone, and soft tissue. The invention of new equipment and techniques is expanding the criteria of eligible patients for therapy, as now larger and more high-risk tumors near critical structures can be ablated. This article provides an overview of the different imaging modalities, noninvasive, and percutaneous ablation techniques available and discusses their applications and associated complications across various organs.

Image-Guided Percutaneous Ablation for Primary and Metastatic Tumors

Image-guided percutaneous ablation methods have been further developed during the recent two decades and have transformed the minimally invasive and precision features of treatment options targeting primary and metastatic tumors. They work by percutaneously introducing applicators to precisely destroy a tumor and offer much lower risks than conventional methods. There are usually shorter recovery periods, less bleeding, and more preservation of organ parenchyma, expanding the treatment options of patients with cancer who may not be eligible for resection. Image-guided ablation techniques are currently utilized for the treatment of primary and metastatic tumors in various organs including the liver, pancreas, kidneys, thyroid and parathyroid, prostate, lung, bone, and soft tissue. This article provides a brief review of the various imaging modalities and available ablation techniques and discusses their applications and associated complications in various organs.

A novel inflammation-related prognostic biomarker for predicting the disease-free survival of patients with colorectal cancer

Background

To develop and evaluate the prognostic value of a comprehensive inflammatory biomarker for postoperative colorectal cancer (CRC) patients.

Methods

A total of 646 CRC patients were recruited between August 2017 and December 2019 from Fujian Medical University Union Hospital, with follow-up data up to 2021. The least absolute shrinkage and selection operator method (LASSO) was used to select inflammation indicators in order to construct a comprehensive biomarker (named NSAP). The Cox regression model was utilized to analyze the association between the NSAP and the disease-free survival (DFS) of CRC. Predictive performance and clinical utility of prognostic models were evaluated by area under the curve (AUC) and decision curve analyses (DCAs).

Results

During a median follow-up of 23 months, 95 clinical outcomes were observed, with a 1-year survival rate is 89.47%. A comprehensive inflammatory biomarker (NSAP) was established based on four blood indicators (including neutrophil-to-lymphocyte ratio (NLR), neutrophil×monocyte-to-lymphocyte ratio (SIRI), albumin-to-globulin ratio (AGR), and platelet-to-lymphocytes ratio (PLR)). Patients with a lower NSAP had significantly associated with better DFS of CRC (HR=0.53, 95%CI 0.32–0.89). Moreover, compared to a previously established model, the traditional TNM staging system or/and tumor markers, the nomogram based on NSAP displayed more excellent predictive ability (0.752 vs 0.597, 0.711 and 0.735, P < 0.05). DCAs also demonstrated that the established nomogram had better utility for decision making.

Conclusions

Our study suggests that NSAP may be a useful comprehensive prognostic biomarker for predicting the DFS of CRC patients. The nomogram based on NSAP can be considered a valuable tool to estimate the prognosis of patients with CRC.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12957-022-02550-0.

Cause Analysis and Diagnosis and Treatment of Intestinal Fistulas After Ultrasound-Guided Microwave Ablation of Abdominopelvic Lesions

Objective: To determine the cause and high-risk factors for the development of intestinal fistulas (IFs) after ultrasound-guided microwave ablation (MA) of abdominopelvic lesions, and to identify effective prophylactic and therapeutic actions. Methods: Clinical data were collected from patients with an IF after ultrasound-guided MA of abdominopelvic lesions in our hospital from January 1, 2010 to December 31, 2018. The cause, diagnosis, and treatment of IFs in these patients were analyzed. Results: Among 8,969 patients who underwent ultrasound-guided MA of abdominopelvic lesions, eight patients developed IF after MA, Seven patients were discharged after being cured and one died. Conclusion: Abdominopelvic lesions are close to the intestines, so histories of surgery, radiotherapy, and abdominopelvic infection are high-risk factors for IF development after MA of these lesions. Surgical treatment should be provided as soon as an IF is identified.

Percutaneous microwave ablation of renal cell carcinoma: practice guidelines of the ultrasound committee of Chinese medical association, interventional oncology committee of Chinese research hospital association

Imaging-guided percutaneous microwave ablation (MWA) with high thermal efficiency comprises rapid, successful management of small renal cell carcinomas (RCCs) in selected patients. Ultrasound Committee of Chinese Medical Association, Interventional Oncology Committee of Chinese Research Hospital Association developed evidence-based guidelines for MWA of RCCs after systematically reviewing the 1969-2019 literature. Systematic reviews, meta-analyses, randomized controlled trials, cohort, and case-control studies reporting MWA of RCCs were included and levels of evidence assessed. Altogether, 146 articles were identified, of which 35 reported percutaneous MWA for T1a RCCs and 5 articles for T1b RCCs. Guidelines were established based on indications, techniques, safety, and effectiveness of MWA for RCCs, with the goal of standardizing imaging-guided percutaneous MWA treatment of RCCs. Key points Microwave ablation is recommended for managing small renal cell carcinoma in selected patients. Imaging protocols are tailored based on the procedural plan, guidance, and evaluation. Patient's selection evaluation, updated technique information, clinical efficacy, and complications are recommended to standardize management. A joint task force (multidisciplinary team) summarized the key elements of the standardized report.

Prognostic Role of Peripheral Neutrophil-Lymphocyte Ratio (NLR) and Platelet-Lymphocyte Ratio (PLR) in Patients with Rectal Cancer Undergoing Neoadjuvant Chemoradiotherapy

PURPOSE

To investigate the predictive and prognostic role of pretreatment hematological parameters for tumor response and outcomes in locally advanced rectal cancer (LARC) patients undergoing surgery after neoadjuvant chemoradiotherapy (nCRT).

METHODS

From 2010 to 2016, 53 patients with LARC who underwent surgery following nCRT were analyzed. All hematological parameters were obtained from the initial blood tests performed before nCRT. The optimal cutoff values of significant hematological parameters for pathological tumor response (pTR), disease-free survival (DFS), and overall survival (OS) were determined using receiver operating characteristic (ROC) analysis. Patients have categorized into "good" and "poor" response groups according to their pathological results, and clinical-pathologic variables compared between the two groups. All survival analysis was calculated by the Kaplan-Meier method. Uni-multivariate analyses were performed using the Cox proportional hazard model.

RESULTS

In the ROC analysis, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) for OS and absolute platelet count and PLR for DFS were found as significant prognostic factors. In multivariate analysis, surgical margin, ypN stage, and elevated PLR were significantly associated with OS, and likewise, high PLR was found as an independent poor prognostic factor for DFS. The 5-year OS and DFS rates were worse in patients with high PLR group (82.3 vs. 47.3% for OS, p = 0.018 and 88.2 vs. 51.3% for DFS, p = 0.002).

CONCLUSION

Pretreatment high PLR is associated with worse OS and DFS in patients with rectal cancer. To use in daily practice, further studies are needed on its validation.

Ablation of Small Renal Masses

Renal cell carcinoma is most commonly diagnosed in the sixth or seventh decade of life. Historically, surgical extirpation was the gold standard treatment option for small renal masses. However, given the comorbidities in this elderly population, not all patients are candidates for surgery. The development of minimally invasive ablative therapies has solved the surgical dilemma in this patient population. Furthermore, the 2017 American Urological Association guidelines recommends consideration of percutaneous image guided thermal ablation as a treatment option for masses smaller than 3 cm even in healthy individuals. Percutaneous image guided thermal ablation is an attractive treatment option providing excellent local tumor control, fewer complications, better preservation of the renal functions, faster recovery and shorter hospital stay. Various ablative modalities are available in clinical practice. This includes radiofrequency ablation, cryoablation, microwave ablation, irreversible electroporation, high intensity focused ultrasound, and laser ablation. In this review, we focus on the most commonly used modalities including radiofrequency ablation and cryoablation and to a lesser extent microwave ablation and irreversible electroporation.

Significance of neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-monocyte ratio and prognostic nutritional index for predicting clinical outcomes in T1-2 rectal cancer

Background

Inflammation-related parameters have been revealed to have prognostic value in multiple caners. However, the significance of some inflammation-related parameters, including the peripheral blood neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), lymphocyte-to-monocyte ratio (LMR) and prognostic nutritional index (PNI), remains controversial in T1–2 rectal cancer (RC).

Methods

Clinical data of 154 T1–2 RC patients were retrospectively reviewed. The cut-off values for NLR, PLR, LMR, and PNI were determined by receiver operating characteristic curves. The relationships of these parameters with postoperative morbidities and prognosis were statistically analysed.

Results

The optimal cut-off values for preoperative NLR, PLR, LMR and PNI were 2.8, 140.0, 3.9, and 47.1, respectively. Significant but heterogeneous associations were found between NLR, PLR, LMR and PNI and clinicopathological factors. In addition, high NLR, high PLR, and low PNI were correlated with an increased postoperative morbidity rate. Patients with high NLR/PLR or low LMR/PNI had lower OS and DFS rates. On multivariate analysis, only high NLR was identified as an independent risk factor for poor DFS.

Conclusions

NLR, PLR, and PNI are valuable factors for predicting postoperative complications in T1–2 RC patients. A preoperative NLR of more than 2.8 is an independent prognostic factor for poor DFS in T1–2 RC patients.

Percutaneous Microwave Ablation of Histologically Proven T1 Renal Cell Carcinoma

Objectives

To assess the safety and efficacy of percutaneous microwave ablation (MWA) of histologically proven T1 renal cell carcinoma (RCC).

Methods

We analysed patients with a histologically proven RCC (≤ 7 cm) treated by MWA from April 2012–April 2018. Primary and secondary efficacy, local tumour recurrence (LTR), morbidity and mortality were reported. Efficacy was defined as no residual tumour enhancement on follow-up imaging 1 month after the first ablation (primary efficacy) and after re-ablation(s) for residual disease (secondary efficacy). Adverse events (AE) were registered by the Clavien–Dindo classification and the common terminology criteria for AE. Univariable and multivariable logistic regression analyses were performed to investigate a relation among pre-treatment factors incomplete ablation and complications.

Results

In 100 patients, a total of 108 RCCs (85 T1a and 23 T1b) were treated by MWA. Median size was 3.2 cm (IQR 2.4–4.0). Primary efficacy was 89% (95%CI 0.81–0.94) for T1a lesions and 52% (95%CI 0.31–0.73) for T1b lesions (p < 0.001). Fifteen lesions (7 T1a) were re-ablated for residual disease by MWA in one (n = 13) and two (n = 2, both T1b) sessions resulting in secondary efficacy rates of 99% (T1a) and 95% (T1b, p = 0.352). LTR occurred in four tumours (2 T1a, 2 T1b) after 10–60 months. Six (4%) AEs grade > 3–5 were observed (2 T1a, 4 T1b, p = 0.045). Multivariable analysis showed that mR.E.N.A.L. nephrometry was independently associated with incomplete ablation (p = 0.012).

Conclusion

Microwave ablation is safe and effective for T1a and T1b RCC lesions with a significantly lower primary efficacy for T1b lesions.

Comparison of clinical outcome between pyeloperfused versus non-pyeloperfused microwave ablation of renal cell carcinoma

Purpose

We present the outcomes of microwave ablation (MWA) of renal cell carcinoma (RCC) with and without pyeloperfusion.

Material and methods

A retrospective review of patients’ records was undertaken to identify patients with RCC, who were treated with MWA with and without adjunctive pyeloperfusion. The distance between the tumour and ureter as well as the tumour size were measured on axial imaging. Pyeloperfusion was performed in nine patients in this series after placement of a ureteral stent and instilment of diluted contrast into the ureter. MWAs of the tumours were performed under computed tomography (CT) guidance. Hydrodissection was performed to displace at-risk organs. Creatinine was measured as renal function index after and before the procedure. A CT scan was performed at the end of the procedure and also after one, three, and six months, to identify the presence of residual disease and complications.

Results

Eighteen biopsies of proven RCC were treated with 20 sessions of MWA. The average follow-up time for this study was 180 days. The average distance between the ureter and the tumour in axial CT view was 20.8 (± 2.9) mm. Primary efficacy was achieved in 88% of pyeloperfused patients and in 100% of the non-pyeloperfused patients. Two pyeloperfused patients required secondary procedure, and full secondary efficacy was achieved for both. There was only one grade 2 urological complication, which occurred in a patient who underwent pyeloperfusion. Creatinine was not significantly different after the procedure in this study (p-value 0.4).

Conclusion

In this study MWAs of RCCs were successfully performed using pyeloperfusion as a protective measure against thermal injury to the ureter.

Available ablation energies to treat cT1 renal cell cancer: emerging technologies

Purpose

An increasing interest in percutaneous ablation of renal tumors has been caused by the increasing incidence of SRMs, the trend toward minimally invasive nephron-sparing treatments and the rapid development of local ablative technologies. In the era of shared decision making, patient preference for non-invasive treatments also leads to an increasing demand for image-guided ablation. Although some guidelines still reserve ablation for poor surgical candidates, indications may soon expand as evidence for the use of the two most validated local ablative techniques, cryoablation (CA) and radiofrequency ablation (RFA), is accumulating. Due to the collaboration between experts in the field in biomedical engineering, urologists, interventional radiologists and radiation oncologists, the improvements in ablation technologies have been evolving rapidly in the last decades, resulting in some new emerging types of ablations.

Methods

A literature search was conducted to identify original research articles investigating the clinical outcomes of new emerging technologies, percutaneous MWA, percutaneous IRE and SABR, in patients with primary cT1 localized renal cell cancer.

Results

Due to the collaboration between experts in the field in biomedical engineering, urologists, interventional radiologists and radiation oncologists, the improvements in ablation technologies have been evolving rapidly in the last decades. New emerging technologies such as microwave ablation (MWA), irreversible electroporation (IRE) and stereotactic ablative radiotherapy (SABR) seem to be getting ready for prime time.

Conclusion

This topical paper describes the new emerging technologies for cT1 localized renal cell cancer and investigates how they compare to CA and RFA.

Platelet-to-Lymphocyte Ratio and Neutrophil-to-Lymphocyte Ratio Are Not Prognostic Biomarkers in Rectal Cancer Patients with Curative Resection

BACKGROUND

Actual predictors of survival and recurrence for rectal cancer patients undergoing curative resection mostly come from pathological data of surgical specimen. Recently, novel blood biomarkers have been proposed as useful tools in cancer patient management, but few and conflicting data have been reported in rectal cancer. We evaluated the prognostic relevance of preoperative platelet-to-lymphocyte (P/L) ratio and neutrophil-to-lymphocyte (N/L) ratio on survival and recurrence in patients undergoing laparoscopic curative resection for rectal cancer.

METHODS

All consecutive patients who referred for primary rectal disease to the Department of General Surgery in Cittadella (Italy) from June 2005 to September 2015 were retrospectively evaluated. Patients with metastatic disease at surgery were excluded. P/L and N/L ratios were calculated. For patients undergoing neoadjuvant chemo-radiotherapy, pre-treatment data were considered. Follow-up data were updated at December 2016.

RESULTS

One hundred fifty-two patients were included in the study, 49 (32%) received neoadjuvant chemo-radiotherapy. Both P/L and N/L ratios showed poor discriminative performance on 5-year OS and DFS. Time-dependent ROC curves showed no improvements in discriminative performance of P/L and N/L ratios when considering different time endpoints. Multivariable analysis identified CEA-rather than P/L or N/L ratios-as independent predictor of OS and DFS, adjusting for age, tumor stage, and postoperative morbidity.

CONCLUSION

Neither P/L nor N/L ratios were associated with survival after rectal cancer surgery. Further studies on large series might provide insights on the role of these inexpensive blood biomarkers in rectal cancer.

Renal Cell Carcinoma: Alternative Nephron-Sparing Treatment Options for Small Renal Masses, a Systematic Review

BACKGROUND

The standard treatment of T1 renal cell carcinoma (RCC) is (partial) nephrectomy. For patients where surgery is not the treatment of choice, for example in the elderly, in case of severe comorbidity, inoperability, or refusal of surgery, alternative treatment options are available. These treatment options include active surveillance (AS), radiofrequency ablation (RFA), cryoablation (CA), microwave ablation (MWA), or stereotactic body radiotherapy (SBRT). In the present overview, the efficacy, safety, and outcome of these different options are summarized, particularly focusing on recent developments.

MATERIALS AND METHODS

Databases of MEDLINE (through PubMed), EMBASE, and the Cochrane Library were systematically searched according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) criteria. The search was performed in December 2016, and included a search period from 2010 to 2016. The terms and synonyms used were renal cell carcinoma, active surveillance, radiofrequency ablation, microwave ablation, cryoablation and stereotactic body radiotherapy.

RESULTS

The database search identified 2806 records, in total 73 articles were included to assess the rationale and clinical evidence of alternative treatment modalities for small renal masses. The methodological quality of the included articles varied between level 2b and level 4.

CONCLUSION

Alternative treatment modalities, such as AS, RFA, CA, MWA, and SBRT, are treatment options especially for those patients who are unfit to undergo an invasive treatment. There are no randomized controlled trials available comparing surgery and less invasive modalities, leading to a low quality on the reported articles. A case-controlled registry might be an alternative to compare outcomes of noninvasive treatment modalities in the future.

Ultrasound-guided hydrodissection for assisting percutaneous microwave ablation of renal cell carcinomas adjacent to intestinal tracts: a preliminary clinical study

PURPOSE

To evaluate the safety and efficacy of the clinical application of hydrodissection under ultrasound (US) guidance for assisting percutaneous microwave ablation (MWA) for the treatment of renal cell carcinomas (RCCs) adjacent to the intestinal tract.

MATERIALS AND METHODS

From April 2014 to December 2016, clinical data from 24 patients with 25 RCCs were retrospectively analysed. Percutaneous MWA under the assistance of US-guided hydrodissection were performed to treat RCCs with a mean maximal diameter of 3.80 ± 1.60 cm because the distance between the index tumour and the adjacent intestinal tracts were less than 0.5 cm on imaging. The separation success rate of the hydrodissection, technique efficacy rate of the MWA, local tumour progression (LTP), complications, and renal function including serum creatinine (Cr) and blood urea nitrogen (BUN) were assessed.

RESULTS

In total, 28 sessions of hydrodissection and MWA procedures were performed (one procedure in 22 patients and two procedures in 3 patients), and the separation success rate was 100% (28/28). The technique efficacy rate was 100% (25/25), and no LTP occurred. One patient exhibited a major complication (4.2%). Minor complications in 5 patients (20.8%) and side effects in 12 patients (50.0%) occurred. Compared with the pre-MWA levels, there were no significant differences in serum Cr and BUN 1-day post-MWA and at the last follow-up.

CONCLUSIONS

US-guided hydrodissection assistance for percutaneous MWA could be a safe and effective alternative for selected patients with RCCs adjacent to the intestinal tracts and can achieve good local tumour control and renal function preservation.