Prognostic value of the combination of volume, massiveness and fragmentation parameters measured on baseline FDG pet in high-burden follicular lymphoma.

The prognostic value of radiomic quantitative features measured on pre-treatment 18F-FDG PET/CT was investigated in patients with follicular lymphoma (FL). We conducted a retrospective study of 126 FL patients (grade 1-3a) diagnosed between 2006 and 2020. A dozen of PET/CT-derived features were extracted via a software (Oncometer3D) from baseline 18F-FDG PET/CT images. The receiver operating characteristic (ROC) curve, Kaplan-Meier method and Cox analysis were used to assess the prognostic factors for progression of disease within 24 months (POD24) and progression-free survival at 24 months. Four different clusters were identified among the twelve PET parameters analyzed: activity, tumor burden, fragmentation-massiveness and dispersion. On ROC analyses, TMTV, the total metabolic tumor volume, had the highest AUC (0.734) followed by medPCD, the median distance between the centroid of the tumors and their periphery (AUC: 0.733). Patients with high TMTV (HR = 4.341; p < 0.001), high Tumor Volume Surface Ratio (TVSR) (HR = 3.204; p < 0.003) and high medPCD (HR = 4.507; p < 0.001) had significantly worse prognosis in both Kaplan-Meier and Cox univariate analyses. Furthermore, a synergistic effect was observed in Kaplan-Meier and Cox analyses combining these three PET/CT-derived parameters (HR = 12.562; p < 0.001). Having two or three high parameters among TMTV, TVSR and medPCD was able to predict POD24 status with a specificity of 68% and a sensitivity of 75%. TMTV, TVSR and baseline medPCD are strong prognostic factors in FL and their combination better predicts disease prognosis.

Characterization of sacral chordoma and differential diagnosis from other sacral malignancy using [18F]FDG PET/CT.

2-Deoxy-2-[18F]fluoro-D-glucose ([18F]FDG) positron emission tomography (PET)/computed tomography (CT) is known to be a helpful imaging modality for sacral chordoma, but its detailed characteristics have not been fully described. The purpose of our study was to identify the [18F]FDG PET/CT imaging characteristics of sacral chordoma and compare them with other sacral malignancy. This retrospective study included patients who underwent [18F]FDG PET/CT because of a mass involving the sacrum. Investigated visual findings included visual score and distribution, and semiquantitative parameters measured included standardized uptake values (SUVmax, SUVpeak, SUVmean), tumor-to-liver ratio (TLR), metabolic tumor volume (MTV), total lesion glycolysis (TLG), and tumor size. Comparison studies and receiver operating characteristics (ROC) curve analysis were performed to differentiate between sacral chordoma and other sacral malignancy. Ten patients with sacral chordoma were finally included (M:F = 6:4, median age = 67 yr). On [18F]FDG PET/CT, sacral chordomas presented as a mass with minimal-moderate uptake with a usually heterogenous distribution. Compared with 12 patients with other sacral malignancies (M:F = 4:8, median age 42 yr), sacral chordoma showed a significantly lower TLR (median value 2.1 vs 6.3, P = .021). In ROC curve analysis, TLR showed the largest area under the curve (AUC) of 0.79 (cutoff ≤ 4.0; sensitivity 100.0%, specificity 58.3%; P = .004), and SUVmax showed the second largest AUC of 0.73 (cutoff ≤ 6.9; sensitivity 80.0%, specificity 66.7%; P = .034). [18F]FDG PET/CT of sacral chordoma showed minimal-moderate uptake. The TLR of [18F]FDG PET/CT was significantly lower than that of other sacral malignancy and was the most useful parameter for differentiating sacral chordoma, with the largest AUC. SUVmax could be another helpful semiquantitative parameter.

Tumor burden score and carcinoembryonic antigen predict outcomes in patients with intrahepatic cholangiocarcinoma following liver resection: a multi­institutional analysis.

BACKGROUND: The prognostic significance of tumor burden score (TBS) in relation to carcinoembryonic antigen (CEA) has not been investigated among patients undergoing hepatectomy for intrahepatic cholangiocarcinoma (ICC). This study aimed to develop and validate a simplified model, a combination of TBS and CEA (CTC grade), for predicting the long-term outcomes of postoperative ICC patients. METHODS: Patients who underwent curative - intent resection of ICC between 2011 and 2019 were identified from a large multi - institutional database. The impact of TBS, CEA, and the CTC grade on overall survival (OS) and recurrence - free survival (RFS) was evaluated in both the derivation and validation cohorts. The receiver operating characteristic curve was utilized for assessing the predictive accuracy of the model. Subgroup analyses were performed across 8th TNM stage system stratified by CTC grade to assess the discriminatory capacity within the same TNM stage. RESULTS: A total of 812 patients were included in the derivation cohort and 266 patients in the validation cohort. Survival varied based on CEA (low: 36.7% vs. high: 9.0%) and TBS (low: 40.3% vs. high: 17.6%) in relation to 5 - year survival (both p < 0.001). As expected, patients with low CTC grade (i.e., low TBS/low CEA) were associated with the best OS as well as RFS, while high CTC grade (i.e., high TBS/high CEA) correlated to the worst outcomes. The model exhibited well performance in both the derivation cohort (area under the curve of 0.694) and the validation cohort (0.664). The predictive efficacy of the CTC grade system remains consistently stable across TNM stages I and III/IV. CONCLUSION: The CTC grade, a composite parameter derived from the combination of TBS and CEA levels, served as an easy - to - use tool and performed well in stratifying patients with ICC relative to OS and RFS.

Reducing and controlling metabolic active tumor volume prior to CAR T-cell infusion can improve survival outcomes in patients with large B-cell lymphoma.

Bridging therapy before CD19-directed chimeric antigen receptor (CAR) T-cell infusion is frequently applied in patients with relapsed or refractory Large B-cell lymphoma (r/r LBCL). This study aimed to assess the influence of quantified MATV and MATV-dynamics, between pre-apheresis (baseline) and pre-lymphodepleting chemotherapy (pre-LD) MATV, on CAR T-cell outcomes and toxicities in patients with r/r LBCL. MATVs were calculated semi-automatically at baseline (n = 74) and pre-LD (n = 68) in patients with r/r LBCL who received axicabtagene ciloleucel. At baseline, patients with a low MATV (< 190 cc) had a better time to progression (TTP) and overall survival (OS) compared to high MATV patients (p < 0.001). High MATV patients who remained stable or reduced upon bridging therapy showed a significant improvement in TTP (p = 0.041) and OS (p = 0.015), compared to patients with a high pre-LD MATV (> 480 cc). Furthermore, high MATV baseline was associated with severe cytokine release syndrome (CRS, p = 0.001). In conclusion, patients with low baseline MATV had the best TTP/OS and effective reduction or controlling MATV during bridging improved survival outcomes in patients with a high baseline MATV, providing rationale for the use of more aggressive bridging regimens.

Construction of a prognostic model for hepatocellular carcinoma patients receiving transarterial chemoembolization treatment based on the Tumor Burden Score.

BACKGROUND: Patients with hepatocellular carcinoma (HCC) who undergo transarterial chemoembolization (TACE) may have varied outcomes based on their liver function and tumor burden diversity. This study aims to assess the prognostic significance of the tumor burden score (TBS) in these patients and develop a prognostic model for their overall survival. METHODS: The study involved a retrospective analysis of 644 newly diagnosed HCC patients undergoing TACE treatment. The individuals were assigned randomly to a training cohort (n = 452) and a validation cohort (n = 192). We utilized a multivariate Cox proportional risk model to identify independent preoperative predictive factors. We then evaluated model performance using the area under the curve (AUC), consistency index (c-index), calibration curve, and decision curve analysis (DCA) methods. RESULTS: The multivariate analysis revealed four prognostic factors associated with overall survival: Tumor Burden Score, Tumor Extent, Types of portal vein invasion (PVI), and Child-Pugh score. The total score was calculated based on these factors. The model demonstrated strong discriminative ability with high AUC values and c-index, providing high net clinical benefits for patients. Based on the model's scoring results, patients were categorized into high, medium, and low-risk groups. These results were validated in the validation cohort. CONCLUSIONS: The tumor burden score shows promise as a viable alternative prognostic indicator for assessing tumor burden in cases of HCC. The new prognostic model can place patients in one of three groups, which will estimate their individual outcomes. For high-risk patients, it is suggested to consider alternative treatment options or provide the best supportive care, as they may not benefit significantly from TACE treatment.

Prognostic value of tumor volume doubling time in lung-metastatic adenoid cystic carcinoma.

OBJECTIVES: Lung metastases in adenoid cystic carcinoma (ACC) usually have indolent growth and the optimal timing to start systemic therapy is not established. We assessed ACC lung metastasis tumor growth dynamics and compared the prognostic value of time to progression (TTP) and tumor volume doubling time (TVDT). METHODS: The study included ACC patients with ≥1 pulmonary metastasis (≥5 mm) and at least 2 chest computed tomography scans. Radiology assessment was performed from the first scan showing metastasis until treatment initiation or death. Up to 5 lung nodules per patient were segmented for TVDT calculation. To assess tumor growth rate (TGR), the correlation coefficient (r) and coefficient of determination (R2) were calculated for measured lung nodules. TTP was assessed per RECIST 1.1; TVDT was calculated using the Schwartz formula. Overall survival was analyzed using the Kaplan-Meier method. RESULTS: The study included 75 patients. Sixty-seven patients (89%) had lung-only metastasis on first CT scan. The TGR was overall constant (median R2 = 0.974). Median TTP and TVDT were 11.2 months and 7.5 months. Shorter TVDT (<6 months) was associated with poor overall survival (HR = 0.48; p = 0.037), but TTP was not associated with survival (HR = 1.02; p = 0.96). Cox regression showed that TVDT but not TTP significantly correlated with OS. TVDT calculated using estimated tumor volume correlated with TVDT obtained by segmentation. CONCLUSION: Most ACC lung metastases have a constant TGR. TVDT may be a better prognostic indicator than TTP in lung-metastatic ACC. TVDT can be estimated by single longitudinal measurement in clinical practice.

Predictive value of cyst/tumor volume ratio of pituitary adenoma for tumor cell proliferation.

BACKGROUND: MRI has been widely used to predict the preoperative proliferative potential of pituitary adenoma (PA). However, the relationship between the cyst/tumor volume ratio (C/T ratio) and the proliferative potential of PA has not been reported. Herein, we determined the predictive value of the C/T ratio of PA for tumor cell proliferation. METHODS: The clinical data of 72 patients with PA and cystic change on MRI were retrospectively analyzed. PA volume, cyst volume, and C/T ratio were calculated. The corresponding intraoperative specimens were collected. Immunohistochemistry and hematoxylin-eosin staining were performed to evaluate the Ki67 index and nuclear atypia. Patients were categorized according to the Ki67 index (< 3% and ≥ 3%) and nuclear atypia (absence and presence). Univariate and multivariate analyses were used to identify the significant predictors of the Ki67 index and nuclear atypia. The receiver operating characteristic curve assessed the prediction ability of the significant predictors. RESULTS: Larger tumor volumes, smaller cyst volumes, and lower C/T ratios were found in patients with higher Ki67 indexes and those with nuclear atypia (P < 0.05). C/T ratio was an independent predictor of the Ki67 index (odds ratio = 0.010, 95% confidence interval = 0.000-0.462) and nuclear atypia (odds ratio = 0.010, 95% confidence interval = 0.000-0.250). The predictive value of the C/T ratio did not differ significantly from that of tumor volume (P > 0.05) but was better than that of cyst volume (P < 0.05). The area under the curve of the C/T ratio for predicting the Ki67 index and nuclear atypia was larger than that for predicting cyst volume and tumor volume. CONCLUSIONS: C/T ratios can be used to predict PA tumor proliferation preoperatively. Our findings may facilitate the selection of surgery timing and the efficacy evaluation of surgery.

Lactate acid promotes PD-1+ Tregs accumulation in the bone marrow with high tumor burden of Acute myeloid leukemia.

BACKGROUND: Acute myeloid leukemia (AML) displayed poor response to programmed death-1 (PD-1) blockade therapy. Regulatory T cells (Tregs) was one of major immunosuppressive components in Tumor microenvironment and plays a vital role in the resistance of immunotherapy. Coinhibitory receptors regulate function of regulatory Tregs and are associated with resistance of PD-1 blockade. However, the coinhibitory receptors expression and differentiated status of Tregs in AML patients remain to be unclear. METHODS: Phenotypic determination of Tregs and CD8+ T cells in bone marrow of healthy donors and AML patients was performed by flow cytometry. Coculture experiments of AML and Tregs in vitro were performed and the concentrations of lactate acid (LA) in the supernatant were examined by ELISA. RESULTS: More Tregs differentiated into effector subsets in AML patients. However, PD-1 and T-cell immunoglobulin and immunoreceptor tyrosine-based inhibitory motif domain (TIGIT) expression on Tregs were comparable in healthy donors and AML patients. Further analysis showed that PD-1+ and PD-1+TIGIT+Tregs are more abundant in the bone marrow of patients with higher leukemic load. Moreover, PD-1+ Tregs accumulation was associated with higher level of senescent CD4+ T cells and increased frequencies of exhausted CD4+ as well as CD8+ T cells. Notably, neither Tregs nor their effector subsets were decreased among patients in complete remission. PD-1 expression was significantly downregulated in Tregs after achieving complete remission. Mechanistically, both AML cell line (KG-1α) and primary AML blasts produced high concentration of LA. Blockade of LA by lactate transporter inhibitor abrogated the upregulation of PD-1 by AML cells. CONCLUSION: PD-1+ Tregs accumulation in bone marrow in higher leukemic burden setting was linked to lactate acid secreted by AML blasts and decreased after disease remission. Our findings provided a novel insight into Tregs in AML and possible mechanism for resistance of PD-1 blockade in AML.

MRI-based volumetric tumor parameters before and during chemoradiation predict tumor recurrence and patient survival in locally advanced cervical cancer: a subgroup analysis of a phase II prospective trial.

BACKGROUND: This subgroup analysis of a prospective phase II trial aimed to identify valuable and accessible prognostic factors for overall survival (OS) and progression-free survival (PFS) of patients with locally advanced cervical cancer (LACC). METHODS: Patients with FIGO II to IVA cervical cancer were assessed in this study. All patients underwent concurrent chemoradiotherapy (CCRT) followed by brachytherapy. Tumor parameters based on MRI scans before and during CCRT were evaluated for Overall survival (OS) and Progression-free survival (PFS). RESULTS: A total of 86 patients were included in this analysis with a median follow-up period of 31.7 months. Three-year OS and PFS rates for all patients were 87.1% and 76.5%, respectively. Univariate Cox regression analysis showed that restaging tumor size (rTS) over 2.55 cm (p < 0.001), initial tumor volume (iTV) over 55.99 cc (p < 0.001), downstaging (p = 0.042), and restaging tumor volume (rTV) over 6.25 cc (p = 0.006) were significantly associated with OS. rTS (p < 0.001), iTV (p < 0.001), downstaging (p = 0.027), and rTV (p < 0.001) were identified as significant prognostic factors for PFS. In the stepwise multivariable analysis, only rTS > 2.55 cm showed statistically significant with OS (HR: 5.47, 95% CI 1.80-9.58, p = 0.035) and PFS (HR: 3.83, 95% CI 1.50-11.45; p = 0.025). CONCLUSIONS: Initial tumor size and restaging tumor volume that are easily accessible during radiotherapy provide valuable prognostic information for cervical cancer. MRI-based measurable volumetric scoring system can be readily applied in real-world practice of cervical cancer. CLINICAL TRIAL INFORMATION: This study is a subgroup analysis of prospective trial registered at ClinicalTrials.gov Identifier: NCT02993653.

Metabolic Tumor Volume as Significant Predictor for Chemotherapy Containing PD-L1 Blocker in Extensive Stage Small Cell Lung Cancer.

BACKGROUND/AIM: Chemo-immunotherapy, including the programmed death ligand 1 (PD-L1) antibody, is an effective treatment for patients with extensive-stage small-cell lung cancer (ES-SCLC). However, no biomarker has been established for the prediction of chemo-immunotherapy. Therefore, we investigated the potential of 18F-fluorodeoxyglucose (FDG)-positron emission tomography (PET) as a predictive marker. PATIENTS AND METHODS: Forty-six patients with ES-SCLC who received 18F-FDG-PET immediately before combined platinum-based chemotherapy with PD-L1 blockade as a first-line treatment were eligible, and the maximum standard uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) on 18F-FDG uptake were evaluated. RESULTS: PD-L1 and tumor infiltrative lymphocytes (TILs) were immunohistochemically analyzed in 36 of the 46 patients. A high MTV was significantly associated with poor performance status and low albumin levels, and there was a significant association between low albumin and high TLG. Univariate analysis identified sex, Brinkman index, and MTV as significant predictors of progression-free survival (PFS), and sex, SUVmax, MTV, and TLG as significant factors of overall survival (OS). Multivariate analysis revealed that sex, Brinkman index, and MTV were independent prognostic factors for PFS, and sex, SUVmax, MTV, and TLG were significant predictors of OS. SUVmax was significantly higher in patients with positive PD-L1 expression than in those with negative expression but was not significantly different between positive and negative TILs. Moreover, the levels of MTV and TLG were not closely associated with the levels of PD-L1 and TILs. CONCLUSION: MTV or TLG metabolic tumor activity is suitable for the prediction of chemo-immunotherapy outcomes in patients with ES-SCLC.

Diaphorobacter nitroreducens synergize with oxaliplatin to reduce tumor burden in mice with lung adenocarcinoma.

Lung adenocarcinoma (LADC) is the most common lung cancer and the leading cause of cancer-related deaths globally. Accumulating evidence suggests that the gut microbiota regulates the host response to chemotherapeutic drugs and can be targeted to reduce the toxicity of current chemotherapeutic agents. However, the effect of Diaphorobacter nitroreducens synergized with oxaliplatin on the gut microbiota and their impact on LADC have never been explored. This study aimed to evaluate the anti-cancer effects of D. nitroreducens, oxaliplatin, and their combined treatment on tumor growth in tumor-bearing mice. The composition of gut microbiota and the immune infiltration of tumors were evaluated by using 16S rRNA gene high-throughput sequencing and immunofluorescence, respectively. The inhibitory effect of the combination treatment with D. nitroreducens and oxaliplatin was significantly stronger than that of oxaliplatin alone in tumor-bearing mice. Furthermore, we observed that the combination treatment significantly increased the relative abundance of Lactobacillus and Akkermansia in the gut microbiota. Meanwhile, the combination treatment significantly increased the proportions of macrophage but decreased the proportion of regulatory T cells in the LADC tumor tissues of mice. These findings underscored the relationship between D. nitroreducens and the gut microbiota-immune cell-LADC axis, highlighting potential therapeutic avenues for LADC treatment. IMPORTANCE: Oxaliplatin is widely used as an effective chemotherapeutic agent in cancer treatment, but its side effects and response rate still need to be improved. Conventional probiotics potentially benefit cancer chemotherapy by regulating gut microbiota and tumor immune infiltration. This study was novel in reporting a more significant inhibitory effect of Diaphorobacter nitroreducens on lung adenocarcinoma (LADC) cells compared with common traditional probiotics and validating its potential as an adjuvant therapy for LADC chemotherapy in mice. This study investigated the impact of D. nitroreducens combined with oxaliplatin on the gut microbiota and immune infiltration of tumors as a potential mechanism to improve anticancer effects.

Tumor and metastatic lymph nodes metabolic activity on 18F-FDG-PET/CT to predict progression-free survival in locally advanced cervical cancer.

OBJECTIVE: The present study investigated the predictive diseases progression value of preoperative fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) in patients with local advanced cervical cancer (LACC). METHODS: In total, 267 patients [median age 58 (range: 27-85) years old] with LACC underwent 18F-FDG PET/CT prior to any treatment. The maximum standardized uptake values (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) of the primary lesion and metastatic lymph nodes were measured on PET/CT and correlated with clinicopathological features and progression-free survival (PFS). RESULTS: The median follow-up was 36.52 (range: 3.09-61.29) months. During the observation period, 80 (30.0%) patients exhibited disease progression. Univariate analysis showed that FIGO stage, concurrent chemoradiotherapy (CRT), serum level of carcinoembryonic antigen (CEA) and squamous cell carcinoma antigen (SCC-Ag), primary tumor MTV (pMTV) and TLG (pTLG), lymph nodes SUVmax (nSUVmax) and TLG (nTLG), and total metabolic activity (sMTV, sTLG) were associated with PFS. nSUVmax ≥ 5.29, CEA ≥ 7.11 ng/ml and deficiency of concurrent CRT were independent risk factor for PFS (p = 0.006, p = 0.008, p = 0.014). The 3-year PFS for patients with high nSUVmax were 42.2% compared to 56.3% for low nSUVmax values. CONCLUSION: Pretreatment cervical and lymph nodes metabolic parameters were associated with PFS in patients with LACC.

Dosage optimization for reducing tumor burden using a phenotype-structured population model with a drug-resistance continuum.

Drug resistance is a significant obstacle to effective cancer treatment. To gain insights into how drug resistance develops, we adopted a concept called fitness landscape and employed a phenotype-structured population model by fitting to a set of experimental data on a drug used for ovarian cancer, olaparib. Our modeling approach allowed us to understand how a drug affects the fitness landscape and track the evolution of a population of cancer cells structured with a spectrum of drug resistance. We also incorporated pharmacokinetic (PK) modeling to identify the optimal dosages of the drug that could lead to long-term tumor reduction. We derived a formula that indicates that maximizing variation in plasma drug concentration over a dosing interval could be important in reducing drug resistance. Our findings suggest that it may be possible to achieve better treatment outcomes with a drug dose lower than the levels recommended by the drug label. Acknowledging the current limitations of our work, we believe that our approach, which combines modeling of both PK and drug resistance evolution, could contribute to a new direction for better designing drug treatment regimens to improve cancer treatment.

Development of a whole spinal MRI-based tumor burden scoring method in participants with multiple myeloma: a pilot study of prognostic significance.

The aim of the study was to develop a new whole spinal MRI-based tumor burden scoring method in participants with newly diagnosed multiple myeloma (MM) and to explore its prognostic significance. We prospectively recruited participants with newly diagnosed MM; performed whole spinal MRI (sagittal FSE T1WI, sagittal IDEAL T2WI, and axial FLAIR T2WI) on them; and collected their clinical data, early treatment response, progression-free survival (PFS), and overall survival (OS). We developed a new tumor burden scoring method according to the extent of bone marrow infiltration in five MRI patterns. All participants were divided into good response and poor response groups after four treatment cycles. Univariate, multivariate analyses, and ROC were used to determine the performance of independent predictors. Thresholds for PFS and OS were calculated using X-tile, and their prognostic significance were assessed by Kaplan-Meier. The Kruskal-Wallis H test was used to compare the differences of tumor burden score between the revised International Staging System (R-ISS) stages. The new tumor burden scoring method was used in 62 participants (median score, 12; range, 0-18). The tumor burden score (OR 1.266, p = 0.002) was an independent predictor of poor response and the AUC was 0.838. Higher tumor burden scores were associated with shorter PFS (p = 0.002) and OS (p = 0.011). The tumor burden score was higher in R-ISS-III than in R-ISS-I and R-ISS-II (p = 0.016 and p = 0.006, respectively). The tumor burden score was an excellent predictor of prognosis and may serve as a supplemental marker for R-ISS.

Tumor Burden Dictates the Neoantigen Features Required to Generate an Effective Cancer Vaccine.

Tumor neoantigens (nAg) represent a promising target for cancer immunotherapy. The identification of nAgs that can generate T-cell responses and have therapeutic activity has been challenging. Here, we sought to unravel the features of nAgs required to induce tumor rejection. We selected clinically validated Great Ape-derived adenoviral vectors (GAd) as a nAg delivery system for differing numbers and combinations of nAgs. We assessed their immunogenicity and efficacy in murine models of low to high disease burden, comparing multi-epitope versus mono-epitope vaccines. We demonstrated that the breadth of immune response is critical for vaccine efficacy and having multiple immunogenic nAgs encoded in a single vaccine improves efficacy. The contribution of each single neoantigen was examined, leading to the identification of 2 nAgs able to induce CD8+ T cell-mediated tumor rejection. They were both active as individual nAgs in a setting of prophylactic vaccination, although to different extents. However, the efficacy of these single nAgs was lost in a setting of therapeutic vaccination in tumor-bearing mice. The presence of CD4+ T-cell help restored the efficacy for only the most expressed of the two nAgs, demonstrating a key role for CD4+ T cells in sustaining CD8+ T-cell responses and the necessity of an efficient recognition of the targeted epitopes on cancer cells by CD8+ T cells for an effective antitumor response. This study provides insight into understanding the determinants of nAgs relevant for effective treatment and highlights features that could contribute to more effective antitumor vaccines. See related Spotlight by Slingluff Jr, p. 382.

Correlation of primary tumor volume and histopathologic response following neoadjuvant treatment of esophageal adenocarcinoma.

INTRODUCTION: In esophageal cancer, histopathologic response following neoadjuvant therapy and transthoracic esophagectomy is a strong predictor of long-term survival. At the present, it is not known whether the initial tumor volume quantified by computed tomography (CT) correlates with the degree of pathologic regression. METHODS: In a retrospective analysis of a consecutive patient cohort with esophageal adenocarcinoma, tumor volume in CT prior to chemoradiotherapy or chemotherapy alone was quantified using manual segmentation. Primary tumor volume was correlated to the histomorphological regression based on vital residual tumor cells (VRTC) (Cologne regression scale, CRS: grade I, >50% VRTC; grade II, 10-50% VRTC; grade III, <10% VRTC and grade IV, complete response without VRTC). RESULTS: A total of 287 patients, 165 with neoadjuvant chemoradiotherapy according to the CROSS protocol and 122 with chemotherapy according to the FLOT regimen, were included. The initial tumor volume for patients following CROSS and FLOT therapy was measured (CROSS: median 24.8 ml, IQR 13.1-41.1 ml, FLOT: 23.4 ml, IQR 10.6-37.3 ml). All patients underwent an Ivor-Lewis esophagectomy. 180 patients (62.7 %) were classified as minor (CRS I/II) and 107 patients (37.3 %) as major or complete responder (CRS III/IV). The median tumor volume was calculated as 24.2 ml (IQR 11.9-40.3 ml). Ordered logistic regression revealed no significant dependence of CRS from tumor volume (OR = 0.99, p-value = 0.99) irrespective of the type of multimodal treatment. CONCLUSION: The initial tumor volume on diagnostic CT does not aid to differentiate between potential histopathological responders and non-responders to neoadjuvant therapy in esophageal cancer patients. The results emphasize the need to establish other biological markers of prediction.

Tumor volume instead of recurrent T category predicts clinical outcome of patients with locally recurrent nasopharyngeal carcinoma salvaged by carbon ion radiation therapy.

BACKGROUND: Although carbon ion radiation therapy (CIRT) substantially improves the overall survival (OS) of patients with LR-NPC, approximately 40% of the patients may develop local recurrence. The purpose of study is to assess the value of tumor volume (TV) as a predictive tool to guide individualized CIRT. METHODS: Consecutive patients with LR-NPC treated using CIRT at Shanghai Proton and Heavy Ion Center between April 2015 and May 2019 were included. TV before CIRT was delineated and calculated. The generalized additive Cox model was used to examine the relationship between TV and OS and local progression-free survival (LPFS). A cutoff value of tumor volume was identified to best discriminate patients with different 2-year OS rates, using receiver operating characteristic (ROC) analysis. RESULTS: A total of 157 patients were enrolled. The median tumor volume was 22.49 (2.52-90.13) ml. In the univariable analyses, tumor volume was significantly associated with OS (p < 0.001) and LPFS (p = 0.01). The relationships with OS (p = 0.009) and LPFS (p = 0.020) remained significant in multivariable analyses. Using ROC analysis, a TV of 26.69 ml was identified to predict the 2-year OS rate. To facilitate potential clinical use, 25 ml was designated as the final cutoff value. The 2-year OS and LPFS rates were 88.6 % vs 62.3 %, and 54.7 % vs 35.5 %, for patients with a TV ≤ 25 ml and > 25 ml, respectively. CONCLUSION: Tumor volume could predict the OS and LPFS of patients. We propose that tumor volume should be considered in the risk stratification and CIRT-based treatment for patients with LR-NPC.

Tumor volume and cancer stem cell expression as prognostic markers for high-dose loco-regional failure in head and neck squamous cell carcinoma - A DAHANCA 19 study.

BACKGROUND AND PURPOSE: Reliable and accessible biomarkers for patients with Head and Neck Squamous Cell Carcinoma (HNSCC) are warranted for biologically driven radiotherapy (RT). This study aimed to investigate the prognostic value of putative cancer stem cell (CSC) markers, hypoxia, and tumor volume using loco-regional high-dose failure (HDF) as endpoint. MATERIALS AND METHODS: Tumor tissue was retrieved from patients treated with primary chemo-(C-)RT and nimorazole for HNSCC in the Danish Head and Neck Cancer Study Group (DAHANCA) 19 study. Tumor volume, hypoxic classification, and expression of CSC markers CD44, SLC3A2, and MET were analyzed. For patients with eligible data on all parameters (n = 340), the risk of HDF following primary chemo-(C-)RT were analyzed by these biomarkers as a whole and stratified for p16-positive oropharynx (p16 + OPSCC) vs p16-negative (p16-) tumors (oral cavity, p16- oropharynx, hypopharynx and larynx). RESULTS: Higher risk of HDF was seen for patients with larger primary and nodal volume (>25 cm3, Hazard Ratio (HR): 3.00 [95 % CI: 1.73-5.18]), high SLC3A2 (HR: 2.99 [1.28-6.99]), CD44 (>30 % positive, HR: 2.29 [1.05-5.00]), and p16- tumors (HR: 2.53 [1.05-6.11]). p16- tumors had a higher CSC marker expression than p16 + OPSCC. The factors associated with the highest risk of HDF were larger volume (HR: 3.29 [1.79-6.04]) for p16- tumors (n = 178) and high SLC3A2 (HR: 6.19 [1.58-24.23]) for p16 + OPSCC (n = 162). CONCLUSION: Tumor volume, p16, and CSC markers are potential biomarkers for HDF for patients with HNSCC treated with (C-)RT. Lower expression of CSC in p16 + OPSCC may contribute to better tumor control.

Improved delineation with diffusion weighted imaging for laryngeal and hypopharyngeal tumors validated with pathology.

OBJECTIVE: This study aims to determine the added value of a geometrically accurate diffusion-weighted (DW-) MRI sequence on the accuracy of gross tumor volume (GTV) delineations, using pathological tumor delineations as a ground truth. METHODS: Sixteen patients with laryngeal or hypopharyngeal carcinoma were included. After total laryngectomy, the specimen was cut into slices. Photographs of these slices were stacked to create a 3D digital specimen reconstruction, which was registered to the in vivo imaging. The pathological tumor (tumorHE) was delineated on the specimen reconstruction. Six observers delineated all tumors twice: once with only anatomical MR imaging, and once (a few weeks later) when DW sequences were also provided. The majority voting delineation of session one (GTVMRI) and session two (GTVDW-MRI), as well as the clinical target volumes (CTVs), were compared to the tumorHE. RESULTS: The mean tumorHE volume was 11.1 cm3, compared to a mean GTVMRI volume of 18.5 cm3 and a mean GTVDW-MRI volume of 15.7 cm3. The median sensitivity (tumor coverage) was comparable between sessions: 0.93 (range: 0.61-0.99) for the GTVMRI and 0.91 (range: 0.53-1.00) for the GTVDW-MRI. The CTV volume also decreased when DWI was available, with a mean CTVMR of 47.1 cm3 and a mean CTVDW-MRI of 41.4 cm3. Complete tumor coverage was achieved in 15 and 14 tumors, respectively. CONCLUSION: GTV delineations based on anatomical MR imaging tend to overestimate the tumor volume. The availability of the geometrically accurate DW sequence reduces the GTV overestimation and thereby CTV volumes, while maintaining acceptable tumor coverage.

The role of 18F-FDG PET in minimizing variability in gross tumor volume delineation of soft tissue sarcomas.

BACKGROUND: Accurate gross tumor volume (GTV) delineation is a critical step in radiation therapy treatment planning. However, it is reader dependent and thus susceptible to intra- and inter-reader variability. GTV delineation of soft tissue sarcoma (STS) often relies on CT and MR images. PURPOSE: This study investigates the potential role of 18F-FDG PET in reducing intra- and inter-reader variability thereby improving reproducibility of GTV delineation in STS, without incurring additional costs or radiation exposure. MATERIALS AND METHODS: Three readers performed independent GTV delineation of 61 patients with STS using first CT and MR followed by CT, MR, and 18F-FDG PET images. Each reader performed a total of six delineation trials, three trials per imaging modality group. Dice Similarity Coefficient (DSC) score and Hausdorff distance (HD) were used to assess both intra- and inter-reader variability using generated simultaneous truth and performance level estimation (STAPLE) GTVs as ground truth. Statistical analysis was performed using a Wilcoxon signed-ranked test. RESULTS: There was a statistically significant decrease in both intra- and inter-reader variability in GTV delineation using CT, MR 18F-FDG PET images vs. CT and MR images. This was translated by an increase in the DSC score and a decrease in the HD for GTVs drawn from CT, MR and 18F-FDG PET images vs. GTVs drawn from CT and MR for all readers and across all three trials. CONCLUSION: Incorporation of 18F-FDG PET into CT and MR images decreased intra- and inter-reader variability and subsequently increased reproducibility of GTV delineation in STS.