Head and neck cancers on CT: preliminary study of treatment response assessment based on computerized volume analysis

Prognostic histological markers in oral tongue squamous cell carcinoma patients treated with (chemo)radiotherapy

Treatment of oral tongue squamous cell carcinoma (OTSCC) frequently includes surgery with postoperative radiotherapy (RT) or chemoradiotherapy (CRT). Resistance to RT or CRT remains a major clinical challenge and highlights the need to identify predictive markers for it. We included 71 OTSCC patients treated with surgery combined with RT or CRT. We evaluated the association between tumor budding, tumor-stroma ratio (TSR), depth of invasion (DOI), tumor-infiltrating lymphocytes (TILs), hypoxia-inducible factor-1alpha (HIF-1alpha) expression, octamer-binding transcription factor 4 (OCT4) expression, high-endothelial venules (HEVs), and disease-free survival (DFS) using uni- and multivariate analyses. No significant association was observed between the different histological and molecular markers (TSR, DOI, TILs, HEV, HIF-1alph, OCT4) and DFS. However, an associative trend between DOI, budding, and DFS was noted. Further studies with larger cohorts are needed to explore the prognostic value of DOI and budding for OTSCC patients treated with postoperative RT or CRT.

Prediction of Disease Free Survival in Laryngeal and Hypopharyngeal Cancers Using CT Perfusion and Radiomic Features: A Pilot Study

(1) Purpose: The objective was to evaluate CT perfusion and radiomic features for prediction of one year disease free survival in laryngeal and hypopharyngeal cancer. (2) Method and Materials: This retrospective study included pre and post therapy CT neck studies in 36 patients with laryngeal/hypopharyngeal cancer. Tumor contouring was performed semi-autonomously by the computer and manually by two radiologists. Twenty-six radiomic features including morphological and gray-level features were extracted by an internally developed and validated computer-aided image analysis system. The five perfusion features analyzed included permeability surface area product (PS), blood flow (flow), blood volume (BV), mean transit time (MTT), and time-to-maximum (Tmax). One year persistent/recurrent disease data were obtained following the final treatment of definitive chemoradiation or after total laryngectomy. We performed a two-loop leave-one-out feature selection and linear discriminant analysis classifier with generation of receiver operating characteristic (ROC) curves and confidence intervals (CI). (3) Results: 10 patients (28%) had recurrence/persistent disease at 1 year. For prediction, the change in blood flow demonstrated a training AUC of 0.68 (CI 0.47-0.85) and testing AUC of 0.66 (CI 0.47-0.85). The best features selected were a combination of perfusion and radiomic features including blood flow and computer-estimated percent volume changes-training AUC of 0.68 (CI 0.5-0.85) and testing AUC of 0.69 (CI 0.5-0.85). The laryngoscopic percent change in volume was a poor predictor with a testing AUC of 0.4 (CI 0.16-0.57). (4) Conclusions: A combination of CT perfusion and radiomic features are potential predictors of one-year disease free survival in laryngeal and hypopharyngeal cancer patients.

3D Segmentation Algorithms for Computerized Tomographic Imaging: a Systematic Literature Review

This paper presents a systematic literature review concerning 3D segmentation algorithms for computerized tomographic imaging. This analysis covers articles published in the range 2006-March 2018 found in four scientific databases (Science Direct, IEEEXplore, ACM, and PubMed), using the methodology for systematic review proposed by Kitchenham. We present the analyzed segmentation methods categorized according to its application, algorithmic strategy, validation, and use of prior knowledge, as well as its general conceptual description. Additionally, we present a general overview, discussions, and further prospects for the 3D segmentation methods applied for tomographic images.

Treatment Response Assessment for Bladder Cancer on CT Based on Computerized Volume Analysis, World Health Organization Criteria, and RECIST

OBJECTIVE

The purpose of this study was to evaluate the accuracy of our autoinitialized cascaded level set 3D segmentation system as compared with the World Health Organization (WHO) criteria and the Response Evaluation Criteria In Solid Tumors (RECIST) for estimation of treatment response of bladder cancer in CT urography.

MATERIALS AND METHODS

CT urograms before and after neoadjuvant chemo-therapy treatment were collected from 18 patients with muscle-invasive localized or locally advanced bladder cancers. The disease stage as determined on pathologic samples at cystectomy after chemotherapy was considered as reference standard of treatment response. Two radiologists measured the longest diameter and its perpendicular on the pre- and posttreatment scans. Full 3D contours for all tumors were manually outlined by one radiologist. The autoinitialized cascaded level set method was used to automatically extract 3D tumor boundary. The prediction accuracy of pT0 disease (complete response) at cystectomy was estimated by the manual, autoinitialized cascaded level set, WHO, and RECIST methods on the basis of the AUC.

RESULTS

The AUC for prediction of pT0 disease at cystectomy was 0.78 ± 0.11 for autoinitialized cascaded level set compared with 0.82 ± 0.10 for manual segmentation. The difference did not reach statistical significance (p = 0.67). The AUCs using RECIST criteria were 0.62 ± 0.16 and 0.71 ± 0.12 for the two radiologists, both lower than those of the two 3D methods. The AUCs using WHO criteria were 0.56 ± 0.15 and 0.60 ± 0.13 and thus were lower than all other methods.

CONCLUSION

The pre- and posttreatment 3D volume change estimates obtained by the radiologist's manual outlines and the autoinitialized cascaded level set segmentation were more accurate for irregularly shaped tumors than were those based on RECIST and WHO criteria.

A prognostic volumetric threshold of gross tumor volume in head and neck cancer patients treated with radiotherapy

OBJECTIVES

To determine the prognostic utility of a volumetric threshold for gross tumor volume (GTV) of the primary and nodal disease when accounting for the TNM classification in head and neck cancer (HNC) patients treated with definitive radiotherapy (RT).

MATERIALS AND METHODS

From 2004 to 2011, 79 HNC patients were treated to a median dose of 70 Gy, using intensity-modulated RT in 78.5% and 3-dimensional conformal RT in 21.5% with 83.5% receiving concurrent chemotherapy. Primary (GTV-P) and nodal (GTV-N) GTVs were derived from computed tomography (CT)-based contours for RT planning, of which 89.7% were aided by positron emission tomography-computed tomography. Local (LC), nodal (NC), distant (DC) control, and overall survival (OS) were assessed using the Kaplan-Meier product-limit method.

RESULTS

With a median follow-up of 27.1 months GTV-P, threshold of <32.9 mL (mean value) compared with ≥32.9 mL, correlated with improved 2-year LC (96.2% vs. 63.9%, P<0.0001), NC (100% vs. 69.2%, P<0.0001), DC (87.9% vs. 64.2%, P=0.001), and OS (88.4% vs. 58.6%, P=0.001). GTV-P demonstrated its prognostic utility in multivariate analyses when adjusted for tumor category, cancer site, and chemotherapy regimen. Nodal GTV (mean, 34.0 mL) was not predictive of nodal control and survival.

CONCLUSIONS

A volumetric threshold of the primary tumor may be used as an independent prognostic factor in patients with HNC undergoing definitive RT.

Inter- and intra-rater reliability of blood and cerebrospinal fluid flow quantification by phase-contrast MRI

PURPOSE

To evaluate the intra- and inter-rater reliability of the quantification of blood and CSF flow rates by phase contrast MRI.

MATERIALS AND METHODS

Blood and CSF flows in the upper cervical region were imaged with velocity-encoded cine-phase contrast using 3T scanners from different manufacturers at two centers. Data of 6 subjects scanned in center A and of 5 subjects in center B were analyzed by six readers at two levels of training. Each data set was analyzed three times in a randomized order for a total of 33 data sets. Intra-class correlation coefficients (ICC) were calculated for the primary measurements of areas and flow rates through the main cervical arteries, veins and the CSF space, and for secondary parameters derived from the individual flow rates.

RESULTS

ICC ranged from 0.80 to 0.96 for the lumen area and from 0.97 to 0.99 for the volumetric flow rate. The ICC for the derived secondary measures ranged from 0.85 to 0.99. Differences due to operator level of training were not statistically significant.

CONCLUSION

High intra- and inter-rater reliability of volumetric flow rate measurements is currently achievable across manufacturers and users' skill levels with a pulsatility based automated lumen segmentation.

Prognostic significance of radiologically determined neck node volume in head and neck cancer: a systematic review

This systematic review addresses the prognostic significance of neck node volume in head and neck cancer. Primary tumor volume evolved as an independent significant factor for survival in head and neck cancer patients. Besides primary tumor volume, multiple prognostic features related to the regional lymph nodes were studied in literature. In literature, some authors showed the significance of total tumor volume/nodal volume for survival and loco-regional control. Articles reporting prognosis and survival in nodal tumor volumes were collected by systematically reviewing publications listed in the Pubmed and Embase databases. Publications were included when they at least reported on total tumor volume (TTV) or nodal volume and survival. In this systematic review we studied 21 articles. For measurement of nodal volume different formulas were used. Until now, there's no clear statistical evidence for the use of either TTV or nodal volume versus primary tumor volume to predict the individual loco-regional control or survival after treatment. There is wide variety of tumor measuring systems in the literature. The cut-off value for local tumor response also shows large variation. Firstly consensus should be accomplished on standardization of volume measurements, preferably automatic, and secondly large study groups are needed with identical treatment modalities to further unravel the role of neck node volume as separate staging tool.

Treatment response assessment of head and neck cancers on CT using computerized volume analysis

BACKGROUND AND PURPOSE

Head and neck cancer can cause substantial morbidity and mortality. Our aim was to evaluate the potential usefulness of a computerized system for segmenting lesions in head and neck CT scans and for estimation of volume change of head and neck malignant tumors in response to treatment.

MATERIALS AND METHODS

CT scans from a pretreatment examination and a post 1-cycle chemotherapy examination of 34 patients with 34 head and neck primary-site cancers were collected. The computerized system was developed in our laboratory. It performs 3D segmentation on the basis of a level-set model and uses as input an approximate bounding box for the lesion of interest. The 34 tumors included tongue, tonsil, vallecula, supraglottic, epiglottic, and hard palate carcinomas. As a reference standard, 1 radiologist outlined full 3D contours for each of the 34 primary tumors for both the pre- and posttreatment scans and a second radiologist verified the contours.

RESULTS

The correlation between the automatic and manual estimates for both the pre- to post-treatment volume change and the percentage volume change for the 34 primary-site tumors was 0.95, with an average error of -2.4 ± 8.5% by automatic segmentation. There was no substantial difference and specific trend in the automatic segmentation accuracy for the different types of primary head and neck tumors, indicating that the computerized segmentation performs relatively robustly for this application.

CONCLUSIONS

The tumor size change in response to treatment can be accurately estimated by the computerized segmentation system relative to radiologists' manual estimations for different types of head and neck tumors.