Deep Learning-Based Segmentation of Locally Advanced Breast Cancer on MRI in Relation to Residual Cancer Burden: A Multiinstitutional Cohort Study

Background: While several methods have been proposed for automated assessment of breast-cancer response to neoadjuvant chemotherapy on breast MRI, limited information is available about their performance across multiple institutions. Purpose: To assess the value and robustness of deep learning-derived volumes of locally advanced breast cancer (LABC) on MRI to infer the presence of residual disease after neoadjuvant chemotherapy. Study Type: Retrospective. Subjects: Training cohort: 102 consecutive female patients with LABC scheduled for neoadjuvant chemotherapy (NAC) from a single institution (age: 25–73 years). Independent testing cohort: 55 consecutive female patients with LABC from four institutions (age: 25–72 years). Field Strength/Sequence: Training cohort: single vendor 1.5 T or 3.0 T. Testing cohort: multivendor 3.0 T. Gradient echo dynamic contrast-enhanced sequences. Assessment: A convolutional neural network (nnU-Net) was trained to segment LABC. Based on resulting tumor volumes, an extremely randomized tree model was trained to assess residual cancer burden (RCB)-0/I vs. RCB-II/III. An independent model was developed using functional tumor volume (FTV). Models were tested on an independent testing cohort and response assessment performance and robustness across multiple institutions were assessed. Statistical Tests: The receiver operating characteristic (ROC) was used to calculate the area under the ROC curve (AUC). DeLong's method was used to compare AUCs. Correlations were calculated using Pearson's method. P values <0.05 were considered significant. Results: Automated segmentation resulted in a median (interquartile range [IQR]) Dice score of 0.87 (0.62–0.93), with similar volumetric measurements (R = 0.95, P < 0.05). Automated volumetric measurements were significantly correlated with FTV (R = 0.80). Tumor volume-derived from deep learning of DCE-MRI was associated with RCB, yielding an AUC of 0.76 to discriminate between RCB-0/I and RCB-II/III, performing similar to the FTV-based model (AUC = 0.77, P = 0.66). Performance was comparable across institutions (IQR AUC: 0.71–0.84). Data Conclusion: Deep learning-based segmentation estimates changes in tumor load on DCE-MRI that are associated with RCB after NAC and is robust against variations between institutions. Evidence Level: 2. Technical Efficacy: Stage 4

Anosmia after endovascular and open surgical treatment of intracranial aneurysms Clinical article

Object. Patients treated for aneurysmal subarachnoid hemorrhage (SAH) often report a loss of smell. To discriminate between the effects of aneurysmal rupture and treatment, the authors assessed the occurrence of anosmia after clipping and coiling of unruptured aneurysms as well as after the coiling of ruptured aneurysms. Methods. The authors interviewed patients in whom an unruptured aneurysm was treated by clipping (32 cases) or endovascular coiling (26 cases) as well as patients with SAH who underwent coil therapy (32 cases). A geographically defined subset of 20 patients per group was invited to undergo olfactory testing. Results. Nine clip-treated patients (28% [95% CI 14-47%]) in the unruptured group reported having anosmia, and no coil-treated patient in the unruptured group (95% [CI 0-13%]) reported having anosmia: in the SAH group, 7 patients (22% [95% CI 9-40%]) reported having anosmia. Anosmia had improved over time in 3 of the clip-treated patients and in all but I of the patients with SAH. Examination revealed olfactory disturbance in 13 (65% [95% CI 41-85%]) of the clip-treated and 8 (42% [95% CI 20-67%]) of the coil-treated patients with unruptured aneurysms, and also in 7 (35% [95% CI 15-59%]) coil-treated patients with SAH. In 20 patients who underwent clip therapy for unruptured aneurysms, 19 (95% [95% CI 75-100%]) had olfactory dysfunction on the side ipsilateral to surgery (anosmia reported by 8 of them). Conclusions. Both clip treatment and SAH contribute to the occurrence of anosmia, with different chances of improvement. Olfactory dysfunction occurs in almost all patients on the side of surgery and can occur subclinically after coil deployment. (DOI: 10.3171/2008.8.JNS08761

Focal salvage iodine-125 brachytherapy for prostate cancer recurrences after primary radiotherapy: a retrospective study regarding toxicity, biochemical outcome and quality of life

Purpose Whole-gland salvage for recurrent prostate cancer (PCa) shows high failure and toxicity rates. Early and adequate localization of recurrences enables focal salvage, thereby potentially improving functional outcomes, while maintaining cancer control. Materials and methods Retrospective analysis yielded 20 focal salvage I125 brachytherapy patients for locally recurrent PCa after primary radiotherapy. Tumor was defined by multiparametric MRI and correspondence with transrectal biopsies. Dose data were obtained intra-operatively. The tumor was prescribed ⩾144 Gy. Toxicity was scored by the Common Terminology Criteria for Adverse Events version 4 (CTCAE-4). Biochemical failure (BF) was defined using the Phoenix criteria (PSA-nadir + 2.0 ng/ml). Quality of life (QoL) was measured by SF-36 Health Survey and European Organization of Research and Treatment of Cancer (EORTC) C30+3 and PR25 questionnaires. Results With a median follow-up of 36 months (range 10–45), six patients experienced BF, of which three had no initial response. Grade 3 genitourinary (GU) toxicity occurred in one patient (a urethral stricture). The five previously potent patients retained erectile function. QoL remained decreased with regard to urinary symptoms. Conclusion Focal salvage I125 brachytherapy showed one grade 3 GU toxicity in the 20 treated patients. Biochemical response and QoL were acceptable

Focal salvage iodine-125 brachytherapy for prostate cancer recurrences after primary radiotherapy: a retrospective study regarding toxicity, biochemical outcome and quality of life

Purpose Whole-gland salvage for recurrent prostate cancer (PCa) shows high failure and toxicity rates. Early and adequate localization of recurrences enables focal salvage, thereby potentially improving functional outcomes, while maintaining cancer control. Materials and methods Retrospective analysis yielded 20 focal salvage I125 brachytherapy patients for locally recurrent PCa after primary radiotherapy. Tumor was defined by multiparametric MRI and correspondence with transrectal biopsies. Dose data were obtained intra-operatively. The tumor was prescribed ⩾144 Gy. Toxicity was scored by the Common Terminology Criteria for Adverse Events version 4 (CTCAE-4). Biochemical failure (BF) was defined using the Phoenix criteria (PSA-nadir + 2.0 ng/ml). Quality of life (QoL) was measured by SF-36 Health Survey and European Organization of Research and Treatment of Cancer (EORTC) C30+3 and PR25 questionnaires. Results With a median follow-up of 36 months (range 10–45), six patients experienced BF, of which three had no initial response. Grade 3 genitourinary (GU) toxicity occurred in one patient (a urethral stricture). The five previously potent patients retained erectile function. QoL remained decreased with regard to urinary symptoms. Conclusion Focal salvage I125 brachytherapy showed one grade 3 GU toxicity in the 20 treated patients. Biochemical response and QoL were acceptable

Deep Learning-Based Segmentation of Locally Advanced Breast Cancer on MRI in Relation to Residual Cancer Burden : A Multiinstitutional Cohort Study

Background: While several methods have been proposed for automated assessment of breast-cancer response to neoadjuvant chemotherapy on breast MRI, limited information is available about their performance across multiple institutions. Purpose: To assess the value and robustness of deep learning-derived volumes of locally advanced breast cancer (LABC) on MRI to infer the presence of residual disease after neoadjuvant chemotherapy. Study Type: Retrospective. Subjects: Training cohort: 102 consecutive female patients with LABC scheduled for neoadjuvant chemotherapy (NAC) from a single institution (age: 25–73 years). Independent testing cohort: 55 consecutive female patients with LABC from four institutions (age: 25–72 years). Field Strength/Sequence: Training cohort: single vendor 1.5 T or 3.0 T. Testing cohort: multivendor 3.0 T. Gradient echo dynamic contrast-enhanced sequences. Assessment: A convolutional neural network (nnU-Net) was trained to segment LABC. Based on resulting tumor volumes, an extremely randomized tree model was trained to assess residual cancer burden (RCB)-0/I vs. RCB-II/III. An independent model was developed using functional tumor volume (FTV). Models were tested on an independent testing cohort and response assessment performance and robustness across multiple institutions were assessed. Statistical Tests: The receiver operating characteristic (ROC) was used to calculate the area under the ROC curve (AUC). DeLong's method was used to compare AUCs. Correlations were calculated using Pearson's method. P values <0.05 were considered significant. Results: Automated segmentation resulted in a median (interquartile range [IQR]) Dice score of 0.87 (0.62–0.93), with similar volumetric measurements (R = 0.95, P < 0.05). Automated volumetric measurements were significantly correlated with FTV (R = 0.80). Tumor volume-derived from deep learning of DCE-MRI was associated with RCB, yielding an AUC of 0.76 to discriminate between RCB-0/I and RCB-II/III, performing similar to the FTV-based model (AUC = 0.77, P = 0.66). Performance was comparable across institutions (IQR AUC: 0.71–0.84). Data Conclusion: Deep learning-based segmentation estimates changes in tumor load on DCE-MRI that are associated with RCB after NAC and is robust against variations between institutions. Evidence Level: 2. Technical Efficacy: Stage 4

Accurate prostate tumour detection with multiparametric magnetic resonance imaging: Dependence on histological properties

<div><p></p><p><i>Background.</i> To benefit most of focal treatment of prostate tumours, detection with high precision of all tumour voxels is needed. Although diffusion-weighted imaging (DWI) and dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) have good diagnostic performance, perfect tumour detection is challenging. In this study, we investigated the variation in prostate tissue characteristics Gleason score (GS), cell density (CD) and microvessel density (MVD) to explain the limitations in tumour voxel detection with a MRI-based logistic regression model. <i>Material and methods.</i> Twelve radical prostatectomy patients underwent a pre-operative 3.0T DWI and DCE-MRI exam. The MRI scans were used to calculate voxel-wise tumour probability with a logistic regression model for the peripheral zone (PZ) of the prostate. Tumour probability maps were correlated and validated with whole-mount histology. Additionally, from the whole-mount histological sections CD, MVD and GS were retrieved for every single voxel. GS, CD and MVD of true- and false-positive voxels and of true- and false-negative voxels were compared using Mann-Whitney U-tests. <i>Results.</i> False-negative tumour voxels had significantly lower CD and MVD (p < 0.0001) and were similar to non-tumour PZ. True-positive detected tumour voxels had high CDs and MVDs (p < 0.0001). In addition, tumour voxels with higher GS showed a trend towards more frequent detection (p = 0.06). Tumour voxels with GS ≥ 3 + 4 showed higher CD and MVD compared to tumour voxels with GS 3 + 3 (p < 0.0001). <i>Conclusion.</i> Tumour voxels with low CD and MVD resemble healthy tissue and are limiting tumour voxel detection using DWI and DCE-MRI. Nevertheless, the most aggressive tumour voxels, containing high CD, MVD and GS, are more likely to be detected and can therefore be treated with high dose using focal therapy or focal boosting.</p></div

Patterns of outcome and toxicity after salvage prostatectomy, salvage cryosurgery and salvage brachytherapy for prostate cancer recurrences after radiation therapy:a multi-center experience and literature review

<p>Current salvage treatments for recurrent prostate cancer after primary radiation therapy include radical prostatectomy, cryosurgery and brachytherapy. Because toxicity and failure rates are considerable, salvage treatments are not commonly performed. As most centers perform only one preferred salvage technique, the literature only describes single-center outcomes from a single salvage technique with a limited number of patients. In this overview, five high-volume Dutch centers describe their toxicity and outcome data using different salvage techniques. This provides a view on how salvage is performed in clinical practice in the Netherlands.</p><p>A total of 129 patients from five different centers in the Netherlands were retrospectively analyzed. Biochemical failure (BF) was defined as PSA > 0.1 ng/ml for the salvage prostatectomy group (n = 44) and PSA nadir + 2.0 ng/ml (Phoenix definition) for the salvage cryosurgery (n = 54) and salvage brachytherapy group (n = 31). Toxicity was scored according to the Common Toxicity Criteria for Adverse events (CTCAE v3.0).</p><p>BF occurred in 25 (81 %) patients in the brachytherapy group (mean follow-up 29 +/- A 24 months), 29 (66 %) patients in the prostatectomy group (mean follow-up 22 +/- A 25 months) and 33 (61 %) patients in the cryosurgery group (mean follow-up 14 +/- A 11 months). Severe (grade > 3) genitourinary and gastrointestinal toxicity was observed in up to 30 % of patients in all three groups.</p><p>This overview shows clinical practice of prostate cancer salvage. Significant failure and toxicity rates are observed, regardless of salvage technique. Patients should be selected with great care before offering these salvage treatment strategies.</p>