Kurdo Barwari

Differentiation between normal renal tissue and renal tumours using functional optical coherence tomography: a phase I in vivo human study.

Whats known on the subject? and What does the study add?

Advanced diagnostics in renal mass using optical coherence tomography: a preliminary report

OBJECTIVE To avoid unnecessary surgical treatment of small renal masses (≤ 4 cm), a more accurate diagnostic method would be desirable since radiological differentiation between malignant and benign is difficult and nondiagnostic biopsies account from 9% to 37%. Optical coherence tomography (OCT) measures backscattered light versus depth, with an attenuation coefficient (μ(t)) that may vary among different histological types. We hypothesize that quantitative measurements of μ(t) using OCT can differentiate between normal renal parenchyma and renal cell carcinoma (RCC). MATERIALS AND METHODS Both normal and tumor renal tissues (RCC) were harvested after partial or radical nephrectomy. Analysis of μ(t) was based on difference of (1) μ(t) between normal and tumor tissue across all patients and (2) μ(t) between normal and tumor tissue within individual patients. RESULTS Tissue samples of 18 patients were measured, of which 4 were excluded (urothelial carcinoma, oncocytoma, and benign lesion without normal tissue available). Of the remaining 14 patients, 8 contributed with both normal and RCC tissue and 6 with only normal or RCC tissue. Independent observation showed a significant difference between the median μ(t) of normal renal tissue (4.95 mm⁻¹) and the median μ(t) of RCC (8.86 mm⁻¹). No statistically significant difference was found when comparing the difference in μ(t) between normal renal parenchyma and RCC within individual patients. CONCLUSION There is a significant difference in μ(t) between normal and RCC tissue across all patients. These results overpower the lack of significant difference within individuals, encouraging further research and suggesting a possible role for OCT in the diagnostic work-up of renal masses.

Clinical, Pathologic, and Functional Outcomes After Nephron-Sparing Surgery in Patients with a Solitary Kidney: A Multicenter Experience

BACKGROUND AND PURPOSE Surgical management of a renal neoplasm in a solitary kidney is a balance between oncologic control and preservation of renal function. We analyzed patients with a renal mass in a solitary kidney undergoing nephron-sparing procedures to determine perioperative, oncologic, and renal functional outcomes. PATIENTS AND METHODS A multicenter study was performed from 12 institutions. All patients with a functional or anatomic solitary kidney who underwent nephron-sparing surgery for one or more renal masses were included. Tumor size, complications, and recurrence rates were recorded. Renal function was assessed with serum creatinine level and estimated glomerular filtration rate. RESULTS Ninety-eight patients underwent 105 ablations, and 100 patients underwent partial nephrectomy (PN). Preoperative estimated glomerular filtration rate (eGFR) was similar between the groups. Tumors managed with PN were significantly larger than those managed with ablation (P<0.001). Ablations were associated with a lower overall complication rate (9.5% vs 24%, P=0.01) and higher local recurrence rate (6.7% vs 3%, P=0.04). Eighty-four patients had a preoperative eGFR ≥60 mL/min/1.73 m(2). Among these patients, 19 (23%) fell below this threshold after 3 months and 15 (18%) at 12 months. Postoperatively, there was no significant difference in eGFR between the groups. CONCLUSIONS Extirpation and ablation are both reasonable options for treatment. Ablation is more minimally invasive, albeit with higher recurrence rates compared with PN. Postoperative renal function is similar in both groups and is not affected by surgical approach.

Laparoscopic renal cryoablation using ultrathin 17-gauge cryoprobes: mid-term oncological and functional results

Study Type – Therapy (case series)

What is the added value of combined core biopsy and fine needle aspiration in the diagnostic process of renal tumours

PurposeNon-diagnostic results still hinder the routine use of core biopsy (CB) and fine needle aspiration (FNA) in the diagnostic process of renal tumours. Furthermore, substantial interobserver variability has been reported. We assessed the added value of combining the results of CB and FNA by five pathologists in the ex vivo diagnosis of renal mass.MethodsTwo ex vivo core biopsies were taken followed by two FNA passes from extirpated tumours. All samples were evaluated by five blinded pathologists. A consensus diagnosis of the surgical specimen was the index for comparison. For each pathologist, the number of non-diagnostic (non-conclusive or undetermined biology and failed biopsies), correct and incorrect scored cases of each technique was assessed. When a non-diagnostic CB or FNA had a correct diagnostic counterpart, this was considered as of added value.ResultsOf the 57 assessed tumours, 53 were malignant. CB was non-diagnostic in 4–10 cases (7–17.5%). FNA established the correct diagnosis in 1–7 of these cases.FNA was non-diagnostic in 2–6 cases (3.5–10.5%), and the counterpart CB established the correct diagnosis in 1–6 of these cases.For the 5 pathologists, accuracy of CB and FNA varied between 82.5–93% and 89.5–96.5%, respectively. Combination of both types of biopsy resulted in 55–57 correct results (accuracy 96.5–100%), i.e., an increase in accuracy of 3.5–14%.ConclusionCombining the result of CB and FNA in renal mass biopsy leads to a higher diagnostic accuracy. Recommendations on which technique used should be adapted to local expertise and logistic possibilities.

Are there parameters that predict a nondiagnostic biopsy outcome taken during laparoscopic-assisted cryoablation of small renal tumors?

BACKGROUND AND PURPOSE The histopathologic diagnosis of a small renal mass (SRM) that is managed with cryoablation relies on preoperative or intraoperative biopsies. Because a considerable number of these SRMs are benign, accurate diagnosis has prognostic and follow-up implications. The main problem in SRMs is the high rate of nondiagnostic biopsies. Our purpose was to assess whether certain tumor and biopsy characteristics are correlated with a diagnostic biopsy outcome. PATIENTS AND METHODS One hundred tumors that were smaller than 4.5 cm in 94 patients were managed with laparoscopic cryoablation. After dissection of the perirenal fat and identification of the tumor by intra-abdominal ultrasonography, one or more biopsies were obtained before freezing. Using the Student t/Mann Whitney U test, the following parameters were evaluated for predicting biopsy outcome: Tumor size, location, and exophytic part of the tumor, size of the biopsy needle, the number of biopsies taken, and presence of nonenhancing areas compatible with necrosis inside the tumors. Correlations among parameters were assessed using a Spearman correlation or Kruskal-Wallis test. RESULTS Twenty-two (22%) biopsies were nondiagnostic and consisted of normal kidney tissue, connective tissue, fat, fibrosis, necrosis, and/or blood. There were no significant differences in parameters between the diagnostic and nondiagnostic group. There was a positive correlation between tumor size and number of biopsies (P=0.029) and between the presence of nonenhancing areas and both size (P<0.001) and the number of biopsies taken (P<0.001). CONCLUSION No statistical significant correlation was found between biopsy outcome and tumor or biopsy characteristics. More biopsies were taken in larger tumors, and larger tumors contained more nonenhancing areas that were suspect for necrosis.