Haralick texture analysis of prostate MRI: utility for differentiating non-cancerous prostate from prostate cancer and differentiating prostate cancers with different Gleason scores

OBJECTIVES

To investigate Haralick texture analysis of prostate MRI for cancer detection and differentiating Gleason scores (GS).

METHODS

One hundred and forty-seven patients underwent T2- weighted (T2WI) and diffusion-weighted prostate MRI. Cancers ≥0.5 ml and non-cancerous peripheral (PZ) and transition (TZ) zone tissue were identified on T2WI and apparent diffusion coefficient (ADC) maps, using whole-mount pathology as reference. Texture features (Energy, Entropy, Correlation, Homogeneity, Inertia) were extracted and analysed using generalized estimating equations.

RESULTS

PZ cancers (n = 143) showed higher Entropy and Inertia and lower Energy, Correlation and Homogeneity compared to non-cancerous tissue on T2WI and ADC maps (p-values: <.0001-0.008). In TZ cancers (n = 43) we observed significant differences for all five texture features on the ADC map (all p-values: <.0001) and for Correlation (p = 0.041) and Inertia (p = 0.001) on T2WI. On ADC maps, GS was associated with higher Entropy (GS 6 vs. 7: p = 0.0225; 6 vs. >7: p = 0.0069) and lower Energy (GS 6 vs. 7: p = 0.0116, 6 vs. >7: p = 0.0039). ADC map Energy (p = 0.0102) and Entropy (p = 0.0019) were significantly different in GS ≤3 + 4 versus ≥4 + 3 cancers; ADC map Entropy remained significant after controlling for the median ADC (p = 0.0291).

CONCLUSION

Several Haralick-based texture features appear useful for prostate cancer detection and GS assessment.

KEY POINTS

• Several Haralick texture features may differentiate non-cancerous and cancerous prostate tissue. • Tumour Energy and Entropy on ADC maps correlate with Gleason score. • T2w-image-derived texture features are not associated with the Gleason score.

Development of a novel straining holder for transmission electron microscopy compatible with single tilt-axis electron tomography

We have developed a newly designed straining specimen holder for in situ transmission electron microscopy (TEM) compatible with high-angle single tilt-axis electron tomography. The holder can deform a TEM specimen under tensile stress with the strain rate between 1.5 × 10(-6) and 5.2 × 10(-3) s(-1). We have also confirmed that the maximum tilt angle of the specimen holder reaches ±60° with a rectangular shape aluminum specimen. The new specimen holder, termed as 'straining and tomography holder', will have wide range potential applications in materials science.

Clinical role of pathological downgrading after radical prostatectomy in patients with biopsy confirmed Gleason score 3 + 4 prostate cancer

OBJECTIVE

To identify preoperative factors predicting Gleason score downgrading after radical prostatectomy (RP) in patients with biopsy Gleason score 3+4 prostate cancer and to determine if prediction of downgrading can identify potential candidates for active surveillance (AS).

PATIENTS AND METHODS

We identified 1317 patients with biopsy Gleason score 3+4 prostate cancers who underwent RP at the Memorial Sloan-Kettering Cancer Center between 2005 and 2013. Several preoperative and biopsy characteristics were evaluated by forward selection regression, and selected predictors of downgrading were analysed by multivariable logistic regression. Decision curve analysis was used to evaluate the clinical utility of the multivariate model.

RESULTS

Gleason score was downgraded after RP in 115 patients (9%). We developed a multivariable model using age, prostate-specific antigen density, percentage of positive cores with Gleason pattern 4 cancer out of all cores taken, and maximum percentage of cancer involvement within a positive core with Gleason pattern 4 cancer. The area under the curve for this model was 0.75 after 10-fold cross validation. However, decision curve analysis revealed that the model was not clinically helpful in identifying patients who will downgrade at RP for the purpose of reassigning them to AS.

CONCLUSION

While patients with pathological Gleason score 3 + 3 with tertiary Gleason pattern ≤4 at RP in patients with biopsy Gleason score 3 + 4 prostate cancer may be potential candidates for AS, decision curve analysis showed limited utility of our model to identify such men. Future study is needed to identify new predictors to help identify potential candidates for AS among patients with biopsy confirmed Gleason score 3 + 4 prostate cancer.

Clinical implications of preoperative serum total cholesterol in patients with clear cell renal cell carcinoma

OBJECTIVE

To investigate the clinical implication of preoperative serum total cholesterol (TC) level in patients with clear cell renal cell carcinoma (RCC).

METHODS

The records of 364 patients with clear cell RCC who had undergone nephrectomy were retrospectively reviewed. The association among preoperative TC level, clinicopathologic factors, and oncological outcome in terms of cancer-specific survival (CSS) and recurrence-free survival period was analyzed by univariate and multivariate analyses.

RESULTS

As a continuous variable, lower serum TC level was found to be significantly associated with male sex, symptomatic tumor, advanced TNM stage, higher nuclear grade, microscopic venous invasion, poor Eastern Cooperative Oncology Group Performance Status, larger tumor size, elevated C-reactive protein level, and lower hemoglobin level. Univariate analysis showed that relatively lower preoperative serum TC level was associated with lower recurrence-free survival (P = .040) and CSS (P <.001) rates. Multivariate analysis indicated that in addition to pT stage, M stage, nuclear grade, and Eastern Cooperative Oncology Group Performance Status, serum TC level (hazard ratio, 0.988 per mg/dL; 95% confidence interval, 0.980-0.998; P = .019) was an independent predictor of CSS.

CONCLUSION

Low preoperative serum TC level is associated with worse prognosis in patients with clear cell RCC. Consideration of preoperative serum TC level might thus provide additional prognostic information for patients with clear cell RCC.

Torsion of a seminoma in an intrascrotal testis: A case report and review of the literature

An intrascrotal testicular torsion with malignant testicular tumour is extremely rare. We report a case of a 26-year-old male who was diagnosed with testicular torsion by magnetic resonance imaging and with testicular seminoma after orchiectomy. Through this case, we found that if the possibility of testicular torsion remains during the diagnosis of acute scrotum cases, additional examination adding to colour Doppler sonography should be performed. Furthermore, we should be aware of the possibility of testicular tumours during the diagnosis and treatment of acute scrotums. If the affected testis is preserved in the treatment of testicular torsion, a postoperative examination by ultrasound and/or tumour markers for the remaining testis is essential to confirm the absence of testicular tumour.

[Urethral condyloma acuminata in an elderly patient : a case report]

A 76-year-old man presented to our hospital with asymptomatic bleeding of the urethra. Endoscopic examination showed multiple urethral papillary tumors in the pendulous urethra, and the tumors were surgically resected. Histopathological examination indicated urethral condyloma acuminata, and the results of a polymerase chain reaction-based invader assay using urethral swabs taken after surgery suggested low risk human papilloma virus infection. This is a relatively rare case because urethral condyloma acuminata has been reported in only a few elderly patients so far. No obvious recurrence of condyloma acuminata has been observed for 18 months after surgery.

Emphysematous cystitis following a transrectal needle guided biopsy of the prostate

Background

Emphysematous cystitis (EC) is a comparatively rare urinary tract infection characterized by air within the bladder wall and lumen and is usually associated with immunosuppression or poorly controlled diabetes mellitus.

Case presentation

We report a case of EC in a 70-year-old man who recently underwent transrectal ultrasound needle-guided prostate biopsy, after which he underwent pylorogastrectomy. He did not have any history of diabetes mellitus or any immunosuppressive disease. The patient developed severe sepsis, requiring intravenous antibiotics and urinary catheterization. Despite therapy, the patient developed disseminated intravascular coagulopathy and acute respiratory distress syndrome. Therefore, he was admitted to the intensive care unit, antibiotic coverage was broadened, and danaparoid sodium and sivelestat sodium hydrate was administered. After 20 days, the patient’s condition improved, and on the 28th day, the patient was discharged to home in a good condition without any sequelae.

Conclusion

Prompt diagnosis and treatment are warranted to prevent potential morbidity of and mortality in cases of EC.

Preoperative prediction of malignant involvement of resected ureters in patients undergoing radical cystectomy for bladder cancer

OBJECTIVE

To investigate preoperative predictors of ureteral involvement of bladder malignancy and to develop a novel preoperative model for the prediction of ureteral involvement in bladder cancer patients undergoing radical cystectomy.

METHODS

This study included 197 consecutive bladder cancer patients treated with radical cystectomy. The correlations of preoperative factors with ureteral involvement were analyzed by univariate analysis with Pearson's χ(2-) test and multivariate logistic regression analysis with a stepwise selection procedure.

RESULTS

Positive ureteral involvement was observed in 38 (19.3%) patients. Tumor location (involvement of the vesical trigone), clinical T stage (≥ cT3) and the number of tumors (≥ 3), but not sex, tumor grade and histological features determined by transurethral resection of bladder tumor, tumor size, shape of tumor, concomitant presence of carcinoma in situ, preoperative intravesical therapy, number of transurethral resection of bladder tumor procedures or the presence of hydronephrosis were significantly associated with ureteral involvement in the univariate analysis. Multivariate logistic regression analysis confirmed that the aforementioned three significant factors identified in the univariate analysis were significant independent predictors of ureteral involvement. The probability of ureteral involvement estimated by a combination of these three parameters was well correlated with the real incidence (R = 0.904, P = 0.0021).

CONCLUSIONS

Tumor location (involvement of vesical trigone), clinical T stage (≥ cT3) and the number of tumors (≥ 3) are significant independent preoperative predictors of ureteral involvement of malignancy in bladder cancer patients undergoing radical cystectomy. Our predictive model might be useful for preoperative prediction of ureteral tumor involvement.

Prognostic value of neutrophil-to-lymphocyte ratio and establishment of novel preoperative risk stratification model in bladder cancer patients treated with radical cystectomy

OBJECTIVE

Preoperative prognostic factors in bladder cancer patients have not been fully established. This study was undertaken to investigate preoperative prognostic factors, including neutrophil-to-lymphocyte ratio (NLR), and to develop a novel prognostic factors-based risk stratification model for disease-specific survival (DSS) in bladder cancer patients treated with radical cystectomy (RC).

METHODS

We performed a retrospective analysis of 189 consecutive bladder cancer patients treated with RC at our institution. Prognostic value of the preoperative clinical and laboratory parameters were evaluated by univariate and multivariate Cox proportional hazard model analyses, and patients were stratified according to relative risks (RRs) for DSS.

RESULTS

One-, 3-, and 5-year DSS rates were 86.8%, 70.8%, and 61.7%, respectively. In univariate analysis, tumor size, clinical T stage, hydronephrosis, concomitance of carcinoma in situ, and some laboratory findings (hemoglobin [Hb] level, platelet count, C-reactive protein, neutrophil count, lymphocyte count, and NLR) were significantly associated with poor prognosis. In multivariate analysis, tumor size, hydronephrosis, Hb level, and NLR were independent factors for predicting poor prognosis. Patients were stratified into 3 risk groups: low (RR = 1.000-3.717), intermediate (RR = 4.149-9.315), and high (RR = 10.397-38.646). The differences among the groups were significant.

CONCLUSIONS

NLR was an independent prognostic factor, as were tumor size, hydronephrosis, and Hb levels, and the combination of these factors can stratify DSS risks in bladder cancer patients treated with RC. This information may be useful for identifying patients who might be candidates for clinical trials of multimodal treatment strategies, including innovative neoadjuvant treatments.

Followup of neutrophil-to-lymphocyte ratio and recurrence of clear cell renal cell carcinoma

PURPOSE

An increase in the pretreatment neutrophil-to-lymphocyte ratio is associated with poor prognosis for various cancers, including renal cell carcinoma. However, the clinical implication of a posttreatment change in the neutrophil-to-lymphocyte ratio in patients with cancer remains unclear.

MATERIALS AND METHODS

We reviewed the records of 250 patients with nonmetastatic clear cell renal cell carcinoma and analyzed associations among clinicopathological variables, the preoperative and postoperative neutrophil-to-lymphocyte ratio, and recurrence-free survival.

RESULTS

The 10-year recurrence-free survival rate for patients with a preoperative neutrophil-to-lymphocyte ratio of 2.7 or greater was significantly lower than that for those with a ratio of less than 2.7 (64.4% vs 83.7%, p = 0.0004). When combined with the postoperative ratio, patients with a preoperative ratio of 2.7 or greater could be further divided into 2 groups with a significantly different prognosis. The 10-year recurrence-free survival rate for patients with a preoperative neutrophil-to-lymphocyte ratio of 2.7 or greater and postoperative ratio of less than 2.7 was significantly lower than that for those with a preoperative and postoperative ratio of 2.7 or greater (52.0% vs 83.5%, p = 0.0487). The latter was similar to the 83.7% for patients with a preoperative ratio of less than 2.7. In patients with recurrence the ratio at recurrence was significantly increased compared with the postoperative ratio (mean ± SD 2.82 ± 1.63 vs 2.00 ± 0.90, p = 0.0090). Multivariate analysis showed that tumor size, pathological tumor stage and the neutrophil-to-lymphocyte ratio change (a combination of the preoperative and postoperative ratios) were independent predictors of recurrence. Using these 3 significant variables patients were stratified into low, intermediate and high risk groups, among which the recurrence-free survival rate significantly differed.

CONCLUSIONS

The posttreatment neutrophil-to-lymphocyte ratio change was a significant prognostic factor for recurrence as well as tumor size and pathological tumor stage in patients with clear cell renal cell carcinoma.