Polyethylene glycol-coated collagen patch (hemopatch®) in open partial nephrectomy

PURPOSE

To describe the results of a polyethylene glycol-coated collagen patch, Hemopatch^® on blood loss, surgical time and renal function in partial nephrectomy (PN) for renal cell carcinoma (RCC).

METHODS

Out of a single surgeon cohort of n = 565 patients undergoing conventional open PN (CPN) between 01/2015 and 12/2017 at the University of Munich a consecutive subgroup (n = 42) was operated on using a polyethylene glycol-coated collagen-based sealant Hemopatch^® (Baxter International Inc., Deerfield, IL, USA) (HPN).

RESULTS

Median age was 65.2 years (range 12.7-95.2) with median follow-up of 9.43 months (0.03-49.15). Baseline renal function (CKD-EPI) was 78.56 ml/min/1.73 m² (range 20.38-143.09) with a non-significant decline to 74.78 ml/min/1.73 m² (range 3.75-167.74) at follow-up. In CPN 46% had low complexity, 33% moderate complexity and 20% high complexity lesions with 33% low, 40% moderate and 27% high complexity masses in HPN. Median tumor size was 4.3 cm (range 1-38 cm) in CPN with 4.8 cm (range 3.8-18.3 cm) with HPN, p = 0.293. Median blood loss and duration of surgery was significantly lower in the HPN group vs. CPN (146 ml ± 195 vs. 114 ml ± 159 ml; p = 0.021; 43 min ± 27 for HPN vs. 53 min ± 49; p = 0.035) with no difference in clamping time (12.6 min ± 8.6 for HPN vs. 12.0 min ± 9.5; p = 0.701).

CONCLUSIONS

Hemopatch^® supported renoraphy shows promising results compared to standard renoraphy in PN. No side effects were seen. Further studies should evaluate the prevention of arterio-venous or urinary fistulas. In complex partial nephrectomies Hemopatch^® supported renoraphy should be considered.

Single‐fraction image‐guided robotic radiosurgery efficiently controls local prostate cancer recurrence after radical prostatectomy

Purpose

To assess the therapeutic potential of single‐fraction robotic stereotactic ablative body radiotherapy (SABR) in patients with locally recurrent prostate cancer (PC) after radical prostatectomy (RP).

Materials and methods

We included 35 patients with biochemical failure after RP with single‐site local recurrence in the prostate bed diagnosed by PSMA PET/CT. About 20/35 pts had previously received post‐surgical adjuvant radiation therapy.

High‐resolution multiparametric magnetic resonance imaging (mpMRI) for exact visualization of tumor tissue was performed at 1.5 (n = 23; Siemens Magnetom Aera) or 3 Tesla (n = 12; Siemens Magnetom VIDA, Siemens Healthineers, Erlangen, Germany). Using the MRI and PET/CT dataset for planning, SABR was carried out after ultrasound‐guided placement of a single gold fiducial marker at the site of tumor recurrence using a CyberKnife M6 unit (Accuray Inc., Sunnyvale, USA). Due to the high diagnostic accuracy of PSMA PET/CT and mpMRI, pre‐SABR biopsy of tumor tissue was not deemed necessary. PSMA PET/CT performed in median 88 days before SABR confirmed the absence of distant metastases. MpMRI was performed at a median of 22 days prior to the intervention. SABR was performed in a single fraction with a dose of 20 (5/35), 21 (27/35) or 22 (3/35) Gy. Follow‐up serum PSA was measured every 3 months thereafter.

Results

Median patient age was 72 years (57‐80 years) and median time from RP to SABR was 96.8 months (IQR, 69.3‐160.2). Median serum PSA before SABR was 1.38 ng/mL (IQR 0.75‐2.72). At 3 months, median PSA had dropped significantly in 27/35 patients to a median of 0.35 ng/mL (IQR 0.25‐0.68). At 6 months, 30/35 patients showed biochemical response to SABR, while five patients were progressing: three had systemic disease on PSMA PET/CT, while two patients had rising PSA values without a visible correlate on PET/CT. The median follow‐up time was 16 months. Grade 1 genitourinary (GU) toxicity was reported in 3/35 patients (9%) and grade 1 gastrointestinal (GI) toxicity in 2/35 patients (6%), respectively.

Conclusion

SABR is an efficient new treatment option in the management of single‐site local recurrent PC without the evidence of systemic disease; due to its very low toxicity, it is an alternative to surgical re‐treatment or other focal therapies. It can significantly delay the onset of androgen deprivation therapy (ADT) in biochemical failure after radical prostatectomy.

[Epidemiology and diagnostic assessment of small renal masses]

BACKGROUND

The incidence of small renal masses has been rising over the last few decades. At the same time, mortality of renal cell carcinoma (RCC) is decreasing. These trends can be explained by the availability of improved therapeutic measures and the good prognosis of small renal masses (SRM) turning out to be histopathologically benign or of low malignancy in many cases.

OBJECTIVES

The aim of this article is to present epidemiology and diagnostic assessment of SRM.

MATERIALS AND METHODS

Statistics, basic research, guidelines.

RESULTS

The incidence of SRM is rising due to the widespread use of imaging techniques such as computed tomography (CT), magnetic resonance imaging (MRI), and contrast-enhanced ultrasound (CEUS). Sensitivity is excellent for CEUS and for CECT in the characterization of SRM, while good specificity values can be reached by MRI. For characterization of complex cystic renal masses, CEUS has good diagnostic accuracy.

CONCLUSIONS

Due to improved diagnostic possibilities, SRMs can be diagnosed in early asymptomatic stages. As SRM have a good prognosis and often are of low malignancy therapy, options should be carefully considered; especially in older patients, active surveillance should considered.

[Cytoreductive, radical prostatectomy in metastatic prostate cancer]

The resection of the primary tumor in patients with metastatic prostate cancer is controversially debated. Retrospective clinical studies indicate survival benefits and prevention of secondary, locoregional complications; however, results of ongoing multicenter prospective studies are still lacking. This review highlights the rationale behind the cytoreductive prostatectomy and summarizes current clinical study results.

[Radical prostatectomy as part of a multimodal concept for patients with prostate cancer and bone metastases at initial diagnosis]

In patients with metastatic prostate cancer presenting with synchronous bone metastases, the surgical removal of the primary is an experimental treatment approach. In the following article, we evaluate the rationale for this approach.

Dual energy can accurately differentiate uric acid-containing urinary calculi from calcium stones

PURPOSE

To retrospectively evaluate the accuracy of dual-energy CT (DECT) in the detection of the chemical composition of urinary calculi in correlation with infrared spectroscopic stone analysis.

METHODS

We reviewed the CT scans of 255 patients who underwent DECT due to a clinical suspicion of urolithiasis. Out of this group, we included 64 patients with clinically symptomatic urolithiasis requiring stone removal. After surgical removal of the stone by ureterorenoscopy, chemical composition was analyzed with infrared spectroscopy. We correlated DECT stone characterization results with chemical stone composition based on dual-energy indices (DEI). A total of 213 renal and ureteral stones could be removed and chemically analyzed.

RESULTS

A total of 213 calculi were evaluated. Thirty eight out of sixty four (59 %) patients had >1 stone. DECT was used to differentiate stones by using DEI. Stones harboring calcium (CA) were color-coded in blue, while stones containing uric acid (UA) were colored red. Median DEI in UA-containing stones were 0.001. Non-UA-containing stones had a DEI between 0.073 for pure CA stones and 0.077 containing CA and other substances (p = 0.001; p = 0.03, respectively). Sensitivity of DECT was 98.4 % for differentiation of UA from non-UA-containing calculi. Specificity was 98.1 %. Mean effective radiation dose of DECT was 4.18 mSv (0.44-14.27 mSv), thus comparable to conventional CT scans of the abdomen. Conventional measurement of Hounsfield units did not correlate with stone composition.

CONCLUSION

DECT with image post-processing reliably discriminates UA-containing calculi from all other stones, but the study offered limitations. Discrimination within the non-UA stones cannot be reliably achieved but is clinically insignificant.

[Sub-threshold prostate-specific antigen levels after resection of metachronous pulmonary metastases]

Radical prostatectomy is a curative therapy for prostate cancer with a lifetime follow-up because there is a high risk of recurrence, especially in the first years of follow-up. In our case disseminated metachronous pulmonary metastases were detected by imaging 4 years after prostatectomy because of elevated levels of serum prostate-specific antigen (PSA). After complete resection of the thoracic metastases the PSA levels have remained below the detection threshold with a recurrence-free survival of 24 months. This case demonstrates that the resection of pulmonary metastases may also be useful for specific individual patients with prostate cancer.

Type-I protein-C deficiency caused by disruption of a hepatocyte nuclear factor (HNF)-6/HNF-1 binding site in the human protein-C gene promoter

The level and tissue specificity of eukaryotic gene transcription is determined by the binding of specific transcription factors to DNA sequence elements located around the transcription start site. The availability and activity of specific transcription factors depends on a variety of developmental and environmental cues and, therefore, varies from cell type to cell type. For instance, liver tissue, the principal site of expression of the coagulation inhibitor protein C, expresses a heterogeneous group of transcription factors called hepatocyte nuclear factors (HNFs). Some of these HNFs are essential players in protein-C gene expression. This review discusses the significance of HNF-1 and HNF-6 in regulating the transcription of the protein-C gene and gives directions for future research.

Promoter analysis of the auxin-regulated tobacco glutathione S-transferase genes Nt103-1 and Nt103-35

We have analysed the promoter regions of two closely related auxin-regulated glutathione S-transferase genes. All active deletion constructs tested showed expression of the reporter gene beta-glucuronidase (gusA) in root tips of young seedlings and newly developing lateral roots. Auxin treatment greatly enhanced the level of expression. The Nt103-1 promoter region -370/-276 was found to be necessary, at least as a quantitative element to confer auxin-responsiveness to a reporter gene, and sequences responsible for the auxin-responsiveness must be located downstream of -370. The region -651/-370 contains sequence information necessary for uninduced expression. The Nt103-35 promoter manifested its auxin-responsiveness within the -504/-310 region. Electrophoretic mobility shift analysis, using nuclear extracts from tobacco leaves and suspension cells, identified a factor binding to a sequence (ap103, TGAGTCT) at position -560 of the Nt103-1 promoter, which shows homology to the mammalian AP-1 site. A second factor was found to bind a sequence (as103, ATAGCTAAGTGCTTACG) with homology to the CaMV 35S promoter as-1 element. The as103 element is present in both promoters and positioned around -360, so within the region determined to be indispensable for the response to auxin. A third factor was found binding to the -276/-190 region of both promoters. Combined, these data point to the relevance of a 90 bp region for auxin-induced activity of both tobacco genes. The ASF-1 like factor binding to the as103 element within this region might be involved in mediating the auxin response.