Molecular-subtype guided automatic invasive breast cancer grading using dynamic contrast-enhanced MRI

BACKGROUND AND OBJECTIVES

Histological grade and molecular subtype have presented valuable references in assigning personalized or precision medicine as the significant prognostic indicators representing biological behaviors of invasive breast cancer (IBC). To evaluate a two-stage deep learning framework for IBC grading that incorporates with molecular-subtype (MS) information using DCE-MRI.

METHODS

In Stage I, an innovative neural network called IOS2-DA is developed, which includes a dense atrous-spatial pyramid pooling block with a pooling layer (DA) and inception-octconved blocks with double kernel squeeze-and-excitations (IOS2). This method focuses on the imaging manifestation of IBC grades and performs preliminary prediction using a novel class F1-score loss function. In Stage II, a MS attention branch is introduced to fine-tune the integrated deep vectors from IOS2-DA via Kullback-Leibler divergence. The MS-guided information is weighted with preliminary results to obtain classification values, which are analyzed by ensemble learning for tumor grade prediction on three MRI post-contrast series. Objective assessment is quantitatively evaluated by receiver operating characteristic curve analysis. DeLong test is applied to measure statistical significance (P < 0.05).

RESULTS

The molecular-subtype guided IOS2-DA performs significantly better than the single IOS2-DA in terms of accuracy (0.927), precision (0.942), AUC (0.927, 95% CI: [0.908, 0.946]), and F1-score (0.930). The gradient-weighted class activation maps show that the feature representations extracted from IOS2-DA are consistent with tumor areas.

CONCLUSIONS

IOS2-DA elucidates its potential in non-invasive tumor grade prediction. With respect to the correlation between MS and histological grade, it exhibits remarkable clinical prospects in the application of relevant clinical biomarkers to enhance the diagnostic effectiveness of IBC grading. Therefore, DCE-MRI tends to be a feasible imaging modality for the thorough preoperative assessment of breast biological behavior and carcinoma prognosis.

Ultra high b-value diffusion weighted imaging enables better molecular grading stratification over histological grading in adult-type diffuse glioma

PURPOSE

Accurate preoperative radiological staging of adult-type diffuse glioma is crucial for effective prognostic stratification and selection of appropriate therapeutic interventions. The purpose of this study was to compare the effectiveness of apparent diffusion coefficient (ADC) maps generated from ultrahigh b-value diffusion-weighted imaging (DWI) for molecular grading with that for histological grading of adult-type diffuse glioma, and to evaluate the correlation between these ADC maps and molecular and histological biomarkers.

METHODS

This study retrospectively enrolled forty adult-type diffuse glioma patients, diagnosed using the 2021 WHO classification criteria. Preoperative imaging data, including multiple b-value DWI and conventional magnetic resonance imaging, were collected. Tumors were graded using both histological and molecular criteria. Histogram analysis was conducted to generate 14 parameters for each tumor. Receiver operating characteristic curves and the area under the curve (AUC) were used to evaluate tumor grading and molecular status differentiation. Analysis of histological biomarkers was performed by calculating the Pearson and Spearman correlation coefficients of continuous and hierarchical variables, respectively.

RESULTS

The intensity-related parameters for molecular grading were found to be superior to those for histological grading for the identification of WHO grade 4 (WHO4) adult-type diffuse glioma. The AUC of both grading systems increased with increasing b-values, with ADC8000-based histogram parameters showing the best results (molecular grading, square root: AUC = 0.897; histological grading, median: AUC = 0.737). The intensity-related parameters could also differentiate molecular WHO4 gliomas from histologically lower-grade gliomas (ADC8000-based square root: AUC = 0.919), and different ADC8000-based kurtosis was observed between molecular and histological WHO4 gliomas (AUC = 0.833). Significant correlations between the Ki-67 index and molecular status prediction for IDH, CDKN2A, and EGFR were also demonstrated.

CONCLUSION

The histogram parameters derived from high b-value ADC maps were found to be more effective for differentiating molecular grades of WHO4 adult-type diffuse glioma than for differentiating histological grades.

Differences in clinical characteristics and outcomes between patients with grade 3a and grades 1-2 follicular lymphoma: a real-world multicenter study

BACKGROUND

The difference between clinical characteristics and outcomes between follicular lymphoma grade 1-2 (FL1-2) and FL3a defined pathologically remains unclear, resulting in uncertainty how to treat FL3a. However, it may be crucial for clinicians to discriminate grade 3a and grade 1-2 for predicting prognosis and thus making treatment decisions.

METHODS

We compared 1403 patients with FL1-2 and 765 patients with FL3a diagnosed between January 2000 and December 2020 from fifteen centers nationwide in China to describe differences in clinical characteristics and outcomes.

RESULTS

Compared with FL1-2 patients, FL3a subgroup had a higher percentage of elderly patients (P = 0.003), and relatively more FL3a patients presented with increased levels of LDH (P < 0.0001) and higher Ki-67 indexs greater than 30% (P < 0.001). More FL3a patients were treated with CHOP ± R (P < 0.0001), and fewer were treated with the watchful-waiting approach (P < 0.0001). The results showed a higher incidence of relapse among FL3a patients, in which more patients underwent histological transformation (HT) when compared to FL1-2 (P = 0.003). 1470 (76.2%) patients of the entire cohort received R-CHOP therapy; survival analysis revealed that FL3a patients had a worse progression-free survival (PFS) rate than FL1-2 patients. Survival of FL3a patients with respect to FLIPI showed an inferior PFS in the intermediate and high-risk groups than FL1-2 patients. FL3a patients had a much worse prognosis than FL1-2 with or without progression of disease within 24 months (POD24). FL3a patients had higher likelihood of lymphoma-related death (LRD, P < 0.05), whereas the rates for non-LRD were comparable.

CONCLUSION

In conclusion, this study demonstrates a marked difference in clinical features and outcomes in FL3a patients compared with FL1-2 patients. The results highlight the need for applying therapeutic approaches distinct from FL1-2 when treating FL3a patients.

[Updates in the pathological diagnosis of Pleural Malignant Mesothelioma in the WHO classification of thoracic tumors (5(th) edition)]

The WHO Classification of Thoracic Tumors (5(th) edition) mainly has the following changes in the chapter of pleural malignant mesothelioma. (1) The concept of mesothelioma in situ and its diagnostic method have been established for the first time; (2) The tumour grading of pleural malignant mesothelioma was added, it was divided into low grade and high grade according to the cellular atypia, mitotic activity and presence of necrosis. (3) The morphological features of pleural malignant mesothelioma was classified into architectural pattern, cellular and stromal features, the correlation between histological features and prognosis was refined, and some of the controversial cellular types have been reclassified. In this review, we introduced the changes of related pathologic diagnosis, in the WHO Classification of Thoracic Tumors (5(th) edition) and discussed its clinical significance.

Low level of interobserver concordance in assessing histological subtype and tumor grade in patients with penile cancer may impair patient care

Differentiation between penile squamous cell carcinoma patients who can benefit from limited organ-sparing surgery and those at significant risk of lymph node metastasis is based on histopathological prognostic factors including histological grade and tumor histological subtype. We examined levels of interobserver and intraobserver agreement in assessment of histological subtype and grade in 207 patients with penile squamous cell carcinoma. The cases were assessed by seven pathologists from three hospitals located in Sweden and Italy. There was poor to moderate concordance in assessing both histological subtype and grade, with Fleiss kappas of 0.25 (range: 0.02-0.48) and 0.23 (range: 0.07-0.55), respectively. When choosing HPV-associated and non-HPV-associated subtypes, interobserver concordance ranged from poor to good, with a Fleiss kappa value of 0.36 (range: 0.02-0.79). A re-review of the slides by two of the pathologists showed very good intraobserver concordance in assessing histological grade and subtype, with Cohen's kappa values of 0.94 and 0.91 for grade and 0.95 and 0.84 for subtype. Low interobserver concordance could lead to undertreatment and overtreatment of many patients with penile cancer, and brings into question the utility of tumor histological subtype and tumor grade in determining patient treatment in pT1 tumors.

Microvascular invasion and grading in hepatocellular carcinoma: correlation with major and ancillary features according to LIRADS

PURPOSE

To assess major and ancillary parameters that could be correlated with Microvascular Invasion (MIV) and with histologic grade of HCC.

MATERIALS AND METHODS

In this retrospective study, we assessed 62 patients (14 women-48 men; mean age, 63 years; range 38-80 years) that underwent hepatic resection for HCC. All patients were subject to Multidetector computed tomography (MDCT); 40 to Magnetic Resonance (MR) study. The radiologist assessed major and ancillary features according to LIRADS (v. 2018) and reported any radiological accessory findings if detected.

RESULTS

No major feature showed statistically significant differences and correlation with grading. Mean ADC value was correlated with grading and with MIV status. No major feature was correlated to MIV; progressive contrast enhancement and satellite nodules showed statistically different percentages with respect to the presence of MIV, so as at the monovariate correlation analysis, satellite nodules were correlated with the presence of MIV. At multivariate regression analysis, no factor proved to be strong predictors of grading while progressive contrast enhancement and satellite nodules were significantly associated with the MIV.

CONCLUSION

Mean ADC value is correlated to HCC grading and MIV status. Progressive contrast enhancement and the presence of satellite nodules are correlated to MIV status.

[CT texture analysis in bladder carcinoma: histologic grade characterization]

Objective: To explore the value of CT texture analysis (CTTA) in differentiating the pathological grade of urothelial carcinoma of the bladder (UCB). Methods: A total of 53 lesions from 43 patients with bladder cancer confirmed by postoperative pathology were retrospectively analyzed, including 27 cases of high-grade urothelial carcinoma (HGUC) and 26 cases of low-grade urothelial carcinoma (LGUC). All the patients took pelvic CT and enhanced scanning in the same CT scanner with same scanning parameters. Lesions on both plain and enhanced CT images were delineated on software by two radiologists to extract the corresponding volumes of interest (VOI) and then 92 parameters based on feature classes were generated. The average values of two radiologists were obtained. The difference parameters between HGUC group and LGUC group were screened by nonparametric test, and the receiver operating characteristic (ROC) was drawn. The corresponding optimal thresholds were determined and diagnostic effect was assessed. Results: Nine difference texture parameters between HGUC group and LGUC group were selected, including 5 parameters on unenhanced images, namely, skewness, root mean squared, cluster shade, zone percentage and large area high gray level emphasis. There were 4 parameters on enhanced images, namely, skewness, kurtosis, cluster shade and zone percentage. The largest area under curve of 0.840±0.058 (95% CI 0.726-0.955) was obtained from skewness generated by VOI of unenhanced images. The cut-off value of skewness was 0.186 5, which permitted the diagnosis of HGUC with sensitivity of 92.59%, specificity of 73.08%, positive predictive value of 78.13%, negative predictive value of 90.48% and accuracy of 83.02%. Conclusion: CTTA can effectively distinguish between LGUC and HGUC. Skewness from unenhanced CT images had the optimal diagnostic performance.

[Classification of pancreatic neuroendocrine tumours: Changes made in the 2017 WHO classification of tumours of endocrine organs and perspectives for the future]

The WHO classification of the tumors of endocrine organs, published in July 2017, has introduced significant changes in the classification of pancreatic neuroendocrine tumors, the previous version of which has appeared in 2010, within the WHO classification of the tumors of the digestive system. The main change is the introduction of a new category of well-differentiated neoplasms, neuroendocrine tumors G3, in addition to the previous categories of neuroendocrine tumors G1 and G2. The differential diagnosis between neuroendocrine tumors G3 (well-differentiated) and neuroendocrine carcinomas (poorly-differentiated) might be difficult; the authors of the WHO classification therefore suggest the use of a number of immunohistochemical markers to facilitate the distinction between the two entities. The other changes are: (a) the modification of the threshold between neuroendocrine tumors G1 and G2, now set at 3%; (b) the terminology used for mixed tumors: the previous term mixed adeno-neuroendocrine carcinoma (MANEC) is substituted by the term mixed neuroendocrine-non neuroendocrine neoplasm (MiNEN). Finally, the recommendations for Ki-67 index evaluation are actualized. Even if these changes only concern, stricto sensu, the neuroendocrine tumors of pancreatic location, they will probably be applied, de facto, for all digestive neuroendocrine tumors. The revision of the histological classification of pancreatic neuroendocrine tumors coincides with the revision of their UICC TNM staging; significant changes have been made in the criteria for T3 and T4 stages. Our professional practices have to take into account all these modifications.

Quantitative CT texture analysis for evaluating histologic grade of urothelial carcinoma

PURPOSE

To investigate the feasibility of using CT texture analysis (CTTA) to differentiate between low- versus high-grade urothelial carcinoma.

METHODS

A total of 105 patients with high-grade urothelial carcinoma (HGUC, n = 106) and low-grade urothelial carcinoma (LGUC, n = 18) were included in this retrospective study. Both unenhanced and enhanced CT images representing the largest cross-sectional area of the tumor were chosen for CTTA performed using TexRAD software. Comparison of texture parameters, mean gray-level intensity (Mean), standard deviation, entropy, mean of positive pixels (MPP), skewness, and kurtosis were made for the objective. Receiver operating characteristic (ROC) analysis was performed and the area under the ROC curve was calculated for texture parameters that were significantly different (P < 0.05) for the purpose. Sensitivity (Se), specificity (Sp), positive predictive value, negative predictive value, and accuracy were calculated using the cut-off value of texture parameter with the highest AUC.

RESULTS

Compared to HGUC, LGUC had significantly lower Mean (P = 0.001), Entropy (P = 0.002), and MPP (P < 0.001) on unenhanced and enhanced images and lower SD (P = 0.048) on enhanced images. There was no significant difference in skewness or kurtosis at any texture scale on unenhanced and enhanced images. A MPP <24.13 at fine texture scale on unenhanced images identified LGUC from HGUC with the highest AUC of 0.779 ± 0.065 (Se = 72.2%, Sp = 84.9%, PPV = 44.8%, NPV = 94.7%, and accuracy = 83.1%).

CONCLUSIONS

CTTA proved to be a feasible tool for differentiating LGUC from HGUC. MPP quantified from fine texture scale on unenhanced images was the optimal diagnostic parameter for estimating histologic grade of urothelial carcinoma.

Professional Practices and Diagnostic Issues in Neuroendocrine Tumour Pathology: Results of a Prospective One-Year Survey among French Pathologists (the PRONET Study)

INTRODUCTION

Many changes have recently occurred in the practice of neuroendocrine tumour (NET) pathology. We therefore aimed to evaluate how pathologists have adapted their daily practice to the most recent international guidelines for diagnostic and prognostic evaluation.

PROCEDURES

A 12-month prospective study (PRONET) was carried out among French pathologists between August 2010 and July 2011. Data were collected using an anonymous electronic case report form.

OBSERVATIONS

Five hundred laboratories were invited, 149 accepted to participate, 80 were active and 59 provided eligible cases. A total of 1,340 cases were collected. The primary tumour was gastroenteropancreatic in 58.1% of cases and thoracic in 18.1%; it was from another site in 9.7%; 12.3% of cases were metastases of unknown origin. Pathological diagnosis was made from the examination of surgical samples in 58.1% of cases, biopsy specimens in 33.5%, endoscopic resections in 3.1% and cytological preparations in 4.2%. For the demonstration of the neuroendocrine nature of the tumour, chromogranin A and synaptophysin were tested in, respectively, 97.1 and 82.8% of cases. The differentiation status was definitely provided in 95.7% of cases. Mitotic count was attempted in 80.1% of cases and Ki67 index in 80.7%. In gastroenteropancreatic (GEP)-NETs, histological grading was available in 95.9% of the cases. WHO classification was available or feasible in 94.1% of GEP-NETs and 93.8% of thoracic NETs. TNM staging was performed according to International Union against Cancer in 74.8% of GEP-NETs and according to European Neuroendocrine Tumour Society in 55.6%.

CONCLUSIONS

The PRONET study shows that the current recommendations and diagnostic procedures are satisfactorily respected by most pathologists in daily practice.

Inter- and intra-observer variability in three grading systems for oral epithelial dysplasia

Background and Objectives:

Management of oral premalignant lesions depends on clinical assessment and grading of oral epithelial dysplasia (OED), which remains one of the most important predictors of malignant potential. Numerous grading systems for OED exists with varying sets of assessing criteria and are largely considered subjective. The present study attempted to assess the inter- and intra-observer variability in three grading systems: Binary system, WHO (2005) and Ljubljana systems.

Methodology:

Histopathological grading of 63 cases of leukoplakia was performed by two oral pathologists and one general pathologist, who were blinded, using all the three grading systems at different time intervals and was repeated twice. Inter- and intra-observer variability was then evaluated by multivariate kappa analysis.

Results:

Inter-observer agreement in the two set of observations was found to be “slight” in WHO (k = 0.001 and 0.039), “slight” and “poor” in binary (k = 0.108 and −0.007), “poor” and “slight” in Ljubljana's (k = −0.027 and 0.106) grading systems. Intra-observer agreement ranged from “slight” to “fair” (k = 0.128 and 0.295) in WHO, “fair” to “moderate” (k = 0.224 and 0.420) in binary and “slight” to “fair” (k = 0.161 and −0.353) in Ljubljana's grading systems.

Conclusions:

The binary system of classification proved to have an overall better inter- and intra-observer agreement. This study also showed better intra-observer agreement in all the grading systems as well as in individual histopathological parameters. Defining the individual parameters more objectively with the reproducible structuring of the grading systems and training of the pathologists would help reduce the variability in diagnosing dysplasia.

Diffusion-weighted imaging of hepatocellular carcinomas: a retrospective analysis of correlation between apparent diffusion coefficients and histological grade

PURPOSE

To define correlations between the pathological grades of hepatocellular carcinomas (HCCs) and apparent diffusion coefficients (ADCs) derived using breath-holding diffusion-weighted imaging (BH-DWI).

METHODS

We retrospectively evaluated 94 patients (105 lesions) with pathologically proved HCC who underwent hepatic DWI on a 3.0-T MR platform. HCCs were divided into five groups: well-differentiated (n = 10), well-to-moderately differentiated (n = 11), moderately differentiated (n = 51), moderately to poorly differentiated (n = 20), and poorly differentiated (n = 13) groups. The ADCs of carcinomas across different histological grades were compared by one-way analysis of variance. Spearman's rank correlation test was used to analyze correlations between the degree of histopathological differentiation and ADC. Results were corrected for multiple comparisons using the Bonferroni correction.

RESULTS

The BH technique yielded ADC values that differed significantly by the extent of differentiation (F = 8.392, p < 0.001). A significant negative correlation was found between the extent of differentiation and ADCs (r = -0.462, p < 0.001). The mean ADC values of poorly differentiated HCCs were significantly lower than the well-, well-to-moderately, moderately, and moderately to poorly differentiated HCCs (p values were <0.001, <0.001, 0.003, and 0.031, respectively).

CONCLUSION

ADC values obtained with BH-DWI may be of importance to non-invasively predict HCC tumor differentiation, and the extent of histological HCC differentiation was inversely correlated with ADC values.

Neurovascular Invasion and Histological Grade Serve as the Risk Factors of Cervical Lymph Node Metastases in Early Tongue Squamous Cell Carcinoma

The objectives of this study were to analyze the regional characteristics of the cervical lymph node metastasis and to investigate the factors associated with the risk of lymph node involvement. One hundred seventy-one patients suffering from early primary squamous cell carcinoma (SCC) of the tongue (cT1-2N0) were enrolled. Gender, age, growth site, T stage, histological grade, and neurovascular invasion were statistically analyzed by K-M survival analysis and Cox multivariate analysis to evaluate the relationship between the factors and the neck lymph node metastasis. Of the 171 cases divided into the neck dissection group and observation group, 40 ended up with lymph node metastasis, of which 17 were metastasized to level I, 27 to level II, 10 to level III, 2 to level IV, and 1 to level V. Histological grade and neurovascular invasion were significantly associated with lymph node involvement in univariate and multivariate analyses. Age distribution was found to be significantly associated with the lymph node metastasis in multivariate analysis. The metastasis of early tongue SCC has a certain regularity at different sites. Age was not a critical risk factor for cervical lymph node metastasis after surgery. Tumor size was suspected to exert a negative effect on metastasis by influencing tumor invasion. Histological grade and neurovascular invasion were significantly associated with the risk of cervical lymph node metastasis of early tongue SCC.

Analysis of salivary antioxidant levels in different clinical staging and histological grading of oral squamous cell carcinoma: noninvasive technique in dentistry

OBJECTIVE

To estimate and Compare of salivary antioxidant level {Uric acid (UA), Glutathione S Transferase (GST) and Superoxide dismutase (SOD)} between healthy control and study group (oral squamous cell carcinoma patients).Further comparison of sub division of study group on the basis of clinical staging and histological grading.

MATERIALS AND METHODS

The study group consists of 50 cases of squamous cell carcinoma and 50 healthy patients. These parameters were estimated by spectrophotometer. The biochemical values of this study were subjected to statistical analysis i.e. Independent t-test, ANOVA and Tukey test.

RESULT

UA suggested statistically significant changes in saliva of clinical staging and histological grading of oral squamous cell carcinoma (SCC) patients. Salivary SOD level between well to poorly differentiated SCC showed a progressive increase although it is not statistically significant.

CONCLUSION

Salivary analysis of antioxidant is simple, non-invasive technique which may be useful as diagnostic, prognostic and therapeutic marker.

Differentiation between dysplastic nodule and early-stage hepatocellular carcinoma: The utility of conventional MR imaging

AIM: To elucidate the variety of ways early-stage hepatocellular carcinoma (HCC) can appear on magnetic resonance (MR) imaging by analyzing T1-weighted, T2-weighted, and gadolinium-enhanced dynamic studies.

METHODS: Seventy-three patients with well-differentiated HCC (wHCC) or dysplastic nodules were retrospectively identified from medical records, and new histological sections were prepared and reviewed. The tumor nodules were categorized into three groups: dysplastic nodule (DN), wHCC compatible with Edmondson-Steiner grade I HCC (w1-HCC), and wHCC compatible with Edmondson-Steiner grade II HCC (w2-HCC). The signal intensity on pre-contrast MR imaging and the enhancing pattern for each tumor were recorded and compared between the three tumor groups.

RESULTS: Among the 73 patients, 14 were diagnosed as having DN, 40 were diagnosed as having w1-HCC, and 19 were diagnosed as having w2-HCC. Hyperintensity measurements on T2-weighted axial images (T2WI) were statistically significant between DNs and wHCC (P = 0.006) and between DN and w1-HCC (P = 0.02). The other imaging features revealed no significant differences between DN and wHCC or between DN and w1-HCC. Hyperintensity on both T1W out-phase imaging (P = 0.007) and arterial enhancement on dynamic study (P = 0.005) showed statistically significant differences between w1-HCC and w2-HCC. The other imaging features revealed no significant differences between w1-HCC and w2-HCC.

CONCLUSION: In the follow-up for a cirrhotic nodule, increased signal intensity on T2WI may be a sign of malignant transformation. Furthermore, a noted loss of hyperintensity on T1WI and the detection of arterial enhancement might indicate further progression of the histological grade.

Improving discrimination in the grading of rat mammary tumors using two-dimensional mapping of histopathological observations

This work aims at characterizing rat mammary tumors induced by 7,12-dimethylbenz(a)anthracene (DMBA) and the respective malignancy potential, commonly graded with histopathology features grouped by intensity levels. Tumors were described over fourteen multiple ranged microscopic parameters and a comprehensive characterization of the histological patterns and their relation with tumor grade was carried out by principal component analysis (PCA). The number of histological patterns present on a tumor tends to correlate with malignant features. High grade tumors are characterized by the presence of several structural patterns, with cribriform prevalence and necrosis. The cribriform pattern correlates with grading, i.e., tumors having a higher predominance of the cribriform pattern are likely to be more malignant. The findings may represent a benchmark for similar characterization studies in other models.