Clinical Outcomes in Patients With DLBCL Treated With R-CHOP According to Radiotherapy and Interim PET Response.

Background/Aim: Interim positron emission tomography/computed tomography (PET/CT) scan is a valuable tool for assessing the early metabolic response to chemotherapy in diffuse large B-cell lymphoma (DLBCL). Although radiotherapy is an effective treatment for lymphoma, especially for local tumor control, the role of consolidative radiotherapy in diffuse large B-cell lymphoma (DLBCL) remains controversial. This study analyzed the clinical outcomes of patients with DLBCL treated with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP), stratified by interim PET response and the administration of radiotherapy. Patients and Methods: We conducted a retrospective review of 107 patients with DLBCL treated with R-CHOP chemotherapy between January 2012 and December 2016. Overall survival (OS), recurrence-free survival (RFS), and freedom from disease progression (FFDP) were calculated using the Kaplan-Meier method and compared using the log-rank test. Results: Forty-six patients were included in this analysis, with a median follow-up time of 65.9 months (range=4.7-125.3 months). The metabolic CR (mCR) group exhibited superior OS, RFS, and FFDP compared with the metabolic PR (mPR) group (p=0.003, p=0.001, and p=0.008, respectively). The 1-, 2-, and 5-year FFDP were 92.97%, 89.3%, and 85.6%, respectively, in the mCR group and 78.6%, 61.9%, and 44.2%, respectively, in the mPR group. In subgroup analysis, the FFDP of the mPR group without radiotherapy was significantly lower than that of the other groups (mCR with/without radiotherapy and mPR with radiotherapy, p=0.001). Conclusion: Consolidative radiation therapy using interim PET can benefit patients who do not achieve mCR. Further well-controlled prospective randomized trials are required.

Prognostic significance of TP53 and PIK3CA mutations analyzed by next-generation sequencing in breast cancer.

Breast cancer is one of the most prevalent malignant tumors affecting women globally. It is a heterogeneous disease characterized by mutations in several genes. Several gene panels have been applied to assess the risk of breast cancer and determine the appropriate treatment. As a powerful tool, Next-generation sequencing (NGS) has been widely utilized in cancer research due to its advantages, including high speed, high throughput, and high accuracy. In this study, we aim to analyze the correlation between somatic mutations in breast cancer, analyzed using NGS, and the prognosis of patients. Between May 2018 and May 2019, a total of 313 patients with breast cancer underwent surgical treatment, which included total mastectomy and breast-conserving surgery. Among these patients, 265 were diagnosed with invasive ductal carcinoma. In this study, we analyzed the NGS results, clinicopathological characteristics, and their correlation with prognosis. Using a gene panel, we examined 143 somatic mutations in solid cancers. Notably, the study population included patients who had received neoadjuvant chemotherapy. The mean age of the patients was 53.1 (±10.28) years, and the median follow-up time was 48 months (range, 8-54). Among the 265 patients, 68 had received prior systemic therapy. Of these, 203 underwent breast-conserving surgery, and 62 underwent a mastectomy. Various somatic mutations were observed in NGS, with the most frequent mutation being PIK3CA mutations, which accounted for 44% of all mutations. TP53 mutations were the second most frequent, and ERBB2 mutations were the third most frequent. TP53 mutations were associated with poor disease-free survival (P = .027), while PIK3CA mutations were associated with better disease-free survival (P = .035) than PIK3CA wild-type. In our study, we identified various somatic mutations in breast cancer. Particularly, we found that TP53 and PIK3CA mutations are potentially associated with the prognosis of breast cancer. These findings suggest that the presence of specific mutations may have implications for predicting the prognosis of breast cancer. Further research and validation are needed to gain a deeper understanding of the role of these mutations and their mechanisms in prognosis prediction.

Clinical features and oncological outcomes of primary female urethral cancer.

PURPOSE: Investigation of the clinical features and treatment outcomes of primary female urethral cancer (FUC) at a single institution. MATERIALS AND METHODS: We retrospectively reviewed 32 FUC patients during 1997-2017. We investigated preoperative risk factors predicting overall (overall survival [OS]) and recurrence-free survival (RFS) and reviewed clinical features, treatment modality, and oncologic outcomes according to pathology. The median follow-up duration and age was 56 months (range: 4-229) and 61 years (range: 15-82), respectively. RESULTS: The median OS and RFS were 70 and 16 months, respectively. A total of 19 (59.4%) patients received systemic chemotherapy, including 14 (43.8%) who received radiation therapy. Further, 22 patients (68.8%) underwent surgery. On univariate analysis, >T2, N+, and tumor size ≥3 cm were associated with poorer OS. There were 15 cases of distant metastasis and five local recurrences. Outcomes were poorest in adenocarcinoma (AC), moderate in clear cell carcinoma and transitional cell carcinoma, and best in squamous cell carcinoma (SCC). CONCLUSION: Female urethral lesions should be carefully examined to exclude FUC. Distal urethral SCC was responsive to surgical excision, but proximal urethral AC had poor oncological outcome even after extensive treatment. Due to the heterogeneity and poor prognosis of FUC, multimodal treatment is mandatory.

Radiofrequency Ablation versus Stereotactic Body Radiation Therapy in the Treatment of Colorectal Cancer Liver Metastases.

PURPOSE: This study aimed to compare the treatment outcomes of radiofrequency ablation (RFA) and stereotactic body radiation therapy (SBRT) for colorectal cancer liver metastases (CRLM) and to determine the favorable treatment modality according to tumor characteristics. MATERIALS AND METHODS: We retrospectively analyzed the records of 222 colorectal cancer patients with 330 CRLM who underwent RFA (268 tumors in 178 patients) or SBRT (62 tumors in 44 patients) between 2007 and 2014. Kaplan-Meier method and Cox models were used by adjusting with inverse probability of treatment weighting (IPTW). RESULTS: The median follow-up duration was 30.5 months. The median tumor size was significantly smaller in the RFA group than in the SBRT group (1.5 cm vs 2.3 cm, p<0.001). In IPTW-adjusted analysis, difference in treatment modality was not associated with significant differences in 1-year and 3-year recurrence-free survival (35% vs 43%, 22% vs 23%; p=0.198), overall survival (96% vs 91%, 58% vs 56%; p=0.508), and freedom from local progression (FFLP; 90% vs 72%, 78% vs 60%; p=0.106). Significant interaction effect between the treatment modality and tumor size was observed for FFLP (p=0.001). In IPTW-adjusted subgroup analysis of patients with tumor size >2 cm, the SBRT group had a higher FFLP compared with the RFA group (HR, 0.153; p<0.001). CONCLUSION: SBRT and RFA showed similar local control in the treatment of patients with CRLM. Tumor size was an independent prognostic factor for local control and SBRT may be preferred for larger tumors.

Role of Esophagectomy after Chemoradiation Therapy in Patients with Locally Advanced Squamous Cell Carcinoma: A Comparative Analysis Stratified by Clinical Response to Chemoradiation Therapy.

PURPOSE: This study aimed to evaluate the long-term effect of esophagectomy in patients with esophageal squamous cell carcinoma (ESCC) by comparing the chemoradiotherapy (CRT)-only group and the trimodality treatment (TMT) group who received concurrent CRT followed by surgery. MATERIALS AND METHODS: We included 412 operable ESCC patients treated with TMT or CRT between January 2005 and December 2015. The oncological outcomes of the two groups were compared using a weighted Cox proportional-hazards model with inverse probability of treatment weighting (IPTW). RESULTS: The median survival time was 64 and 32 months in the TMT (n=270) and CRT (n=142) groups, respectively (p < 0.001). After IPTW, the median overall survival (OS) remained significantly higher in the TMT group than in the CRT group (61 months vs. 32 months, p=0.016). Moreover, the TMT group showed a better local recurrence-free rate (LRFR, p < 0.001) and distant metastasis-free rate (p=0.007). In the subgroup of patients with clinical complete response (cCR), the OS was not significantly different between the two groups, both before and after IPTW adjustment (p=0.35 and p=0.93). However, among non-cCR patients, the OS was significantly higher in the TMT group (64% vs. 45%, p < 0.001). CONCLUSION: In patients with locally advanced ESCC, TMT was superior to CRT in terms of OS and LRFR. Such difference was more prominent in the non-cCR subgroup. In patients who achieved cCR, esophagectomy was effective in improving LRFR but not OS, suggesting that esophagectomy may be omitted in complete responders.

Prevention of radiotherapy induced enteropathy by probiotics (PREP): protocol for a double-blind randomized placebo-controlled trial.

BACKGROUND: Radiation induced enteropathy is a common complication of radiotherapy for pelvic tumors and adversely affects patient quality of life. Probiotics are thought to restore bowel microflora to optimal levels and reinforce intestinal barrier capacity. Although probiotics are effective in the treatment of radiation induced enteropathy, less is known about their efficacy to prevent radiation induced enteropathy. METHODS: This double-blind randomized placebo-controlled study will investigate the efficacy of probiotics to prevent radiation-induced enteropathy in patients with gynecologic or urologic cancer who received pelvic radiotherapy. The study is designed to enroll 248 eligible patients, who will be randomized 1:1 to a probiotic or placebo group. Toxicities will be evaluated using Common Terminology Criteria for Adverse Events (CTCAE) v5.0. DISCUSSION: The primary aim of this study is to provide high level evidence for the ability of probiotics to prevent acute radiation induced enteropathy. The secondary aims are to determine the effects of probiotics on the incidence of chronic radiation induced enteropathy and the safety of probiotics in patients with gynecologic or urologic cancer. TRIAL REGISTRATION: ClinicalTrials.gov ( NCT03978949 , Registered on 7 June 2019).

Definitive chemoradiotherapy versus esophagectomy in patients with clinical T1bN0M0 esophageal squamous cell carcinoma: A retrospective study.

BACKGROUND AND PURPOSE: This study aimed to determine the equivalence between definitive chemoradiotherapy (DCRT) and radical esophagectomy in clinical T1bN0M0 esophageal squamous cell carcinoma (ESCC). MATERIALS AND METHODS: Among 282 patients with cT1bN0M0 ESCC, 238 underwent radical esophagectomy and 44 underwent DCRT. Both treatments were retrospectively compared overall survival (OS), progression-free survival (PFS), and complications. RESULTS: The DCRT group exhibited poorer patient characteristics than the surgery group, especially with mean age (73 vs. 63 years), Eastern Cooperative Oncology Group (ECOG) status, and Charlson Comorbidity Index (p < 0.001, each). The median follow-up duration was 49.5 (range, 0.4-97.0) and 45.5 months (range, 5.0-112.0) in the surgery and DCRT groups, respectively. In the DCRT group, clinical complete response was achieved in 43 patients (97.7%) at 1 month after treatment. The 5-year OS rates were 75.8% and 68.8% (p = 0.135) and the 5-year PFS were 63.8% and 57.8% (p = 0.637) for the surgery and DCRT groups, respectively. Local recurrence rates were identical between the two groups (11.4% and 11.4%), but the distant metastasis rate was lower in the DCRT group (n = 1, 2.27% vs. n = 29, 12.15%). Grade 3-4 hematologic toxicities were observed in 11 patients (25%) of the DCRT group, and 56 patients (23.5%) in the surgery group showed grade 3-5 surgical complications, including mortality (n = 5). CONCLUSION: Based on the non-inferior survival rates, recurrence patterns, and complication rates without critical surgical mortality, DCRT was comparable to esophagectomy for cT1bN0 esophageal squamous cell carcinoma.

Optimizing External Beam Radiotherapy as per the Risk Group of Localized Prostate Cancer: A Nationwide Multi-Institutional Study (KROG 18-15).

PURPOSE: This nationwide multi-institutional study analyzed the patterns of care and outcomes of external beam radiotherapy (EBRT) in localized prostate cancer patients. We compared various risk classification tools and assessed the need for refinements in current radiotherapy (RT) schemes. METHODS AND MATERIALS: We included non-metastatic prostate cancer patients treated with primary EBRT from 2001 to 2015 in this study. Data of 1573 patients from 17 institutions were analyzed and re-grouped using a risk stratification tool with the highest predictive power for biochemical failure-free survival (BCFFS). We evaluated BCFFS, overall survival (OS), and toxicity rates. RESULTS: With a median follow-up of 75 months, 5- and 10-year BCFFS rates were 82% and 60%, and 5- and 10-year OS rates were 95% and 83%, respectively. NCCN risk classification revealed the highest predictive power (AUC = 0.556, 95% CI 0.524-0.588; p < 0.001). Gleason score, iPSA < 12 ng/mL, intensity-modulated RT (IMRT), and ≥179 Gy1.5 (EQD2, 77 Gy) were independently significant for BCFFS (all p < 0.05). IMRT and ≥179 Gy1.5 were significant factors in the high-risk group, whereas ≥170 Gy1.5 (EQD2, 72 Gy) was significant in the intermediate-risk group and no significant impact of dose was observed in the low-risk group. Both BCFFS and OS improved significantly when ≥179 Gy1.5 was delivered using IMRT and hypofractionation in the high-risk group without increasing toxicities. CONCLUSIONS: With NCCN risk classification, dose escalation with modern high-precision techniques might increase survivals in the high-risk group, but not in the low-risk group, although mature results of prospective studies are awaited.

Role of palliative radiotherapy in bleeding control in patients with unresectable advanced gastric cancer.

BACKGROUND: This study analyzed the clinical results of palliative radiotherapy for bleeding control in patients with unresectable advanced gastric cancer. METHODS: We retrospectively reviewed the medical records of patients who met the following inclusion criteria between January 2002 and June 2018: histologically proven gastric cancer, gastric tumor bleeding confirmed by upper gastrointestinal endoscopy, and palliative radiotherapy performed for hemostasis. The median radiotherapy dose was 30 Gy, with a daily dose ranging from 1.8 to 3 Gy. RESULTS: Sixty-one patients were included in this analysis. The study population was predominantly male (72.1%), with a median age of 62 years (range: 32-92). The median baseline hemoglobin level was 7.1 g/dL, and the most common presenting symptom of gastric tumor bleeding was melena (85.2%). Bleeding control was achieved in 54 (88.5%) patients. The median levels of hemoglobin at 1, 2, and 3 months after completion of radiotherapy were 10.1 g/dL, 10.2 g/dL, and 10.4 g/dL, respectively; these values were significantly different from that before radiotherapy (7.1 g/dL; p < 0.001). The median overall survival was 4.8 months. Among the 54 patients who achieved bleeding control after radiotherapy, 19 (35.2%) experienced re-bleeding during the follow-up period. The median time to re-bleeding was 6.0 months. Multivariate analysis demonstrated that a higher radiation dose (p = 0.007) and additional chemotherapy after radiotherapy (p = 0.004) were significant factors for prolonging the time to re-bleeding. CONCLUSIONS: Tumor bleeding was adequately controlled by radiotherapy in patients with unresectable advanced gastric cancer.

Feasibility of automated planning for whole-brain radiation therapy using deep learning.

PURPOSE: The purpose of this study was to develop automated planning for whole-brain radiation therapy (WBRT) using a U-net-based deep-learning model for predicting the multileaf collimator (MLC) shape bypassing the contouring processes. METHODS: A dataset of 55 cases, including 40 training sets, five validation sets, and 10 test sets, was used to predict the static MLC shape. The digitally reconstructed radiograph (DRR) reconstructed from planning CT images as an input layer and the MLC shape as an output layer are connected one-to-one via the U-net modeling. The Dice similarity coefficient (DSC) was used as the loss function in the training and ninefold cross-validation. Dose-volume-histogram (DVH) curves were constructed for assessing the automatic MLC shaping performance. Deep-learning (DL) and manually optimized (MO) approaches were compared based on the DVH curves and dose distributions. RESULTS: The ninefold cross-validation ensemble test results were consistent with DSC values of 94.6 ± 0.4 and 94.7 ± 0.9 in training and validation learnings, respectively. The dose coverages of 95% target volume were (98.0 ± 0.7)% and (98.3 ± 0.8)%, and the maximum doses for the lens as critical organ-at-risk were 2.9 Gy and 3.9 Gy for DL and MO, respectively. The DL technique shows the consistent results in terms of the DVH parameter except for MLC shaping prediction for dose saving of small organs such as lens. CONCLUSIONS: Comparable with the MO plan result, the WBRT plan quality obtained using the DL approach is clinically acceptable. Moreover, the DL approach enables WBRT auto-planning without the time-consuming manual MLC shaping and target contouring.

Prognostic significance of lymph node ratio after neoadjuvant chemoradiation therapy for esophageal squamous cell carcinoma.

PURPOSE: We retrospectively evaluated the prognostic significance of lymph node ratio (LNR) in patients with esophageal squamous cell carcinoma who underwent neoadjuvant concurrent chemoradiation therapy (NCRT) followed by surgery. MATERIALS AND METHODS: In total, 270 patients who underwent NCRT followed by surgery between August 2005 and December 2015 were included. They were divided into three groups: LNR 0 (n = 196), LNR low (0 < LNR ≤ 0.1; n = 63), and LNR high (>0.1; n = 11). The primary endpoint was overall survival (OS), and the secondary endpoints were freedom from local recurrence (FFLR), distant metastasis-free survival (DMFS), and disease-free survival (DFS). RESULTS: The median number of retrieved lymph nodes per patient was 33. Pathologically, 74 patients had positive lymph nodes. The median follow-up duration was 36.1 months, and the median survival period was 68.4 months. There was a significant correlation between LNR and the number of positive lymph nodes (correlation coefficient = 0.763, p < 0.001). There was a substantial difference in the OS among the LNR groups, with 2-year survival rates of 79.0%, 54.0%, and 9.1% in the LNR 0, LNR low, and LNR high groups, respectively (p < 0.001). A marked decrease in FFLP, DMFS, and DFS was observed with the increasing LNR. In subgroup analysis, the survival results of patients with clinically positive lymph node were similar from those of entire cohort. CONCLUSION: LNR is a significant prognostic factor in patients with esophageal squamous cell carcinoma who underwent NCRT followed by surgery. Additional treatment and closer follow-up would be necessary for patients with a high LNR.

Combined Transarterial Chemoembolization and External Beam Radiotherapy in a Patient with Recurrent Huge Hepatocellular Carcinoma after Hepatic Resection.

The optimal treatment strategy for unresectable huge hepatocellular carcinoma (HCC) is yet to be established. Non-surgical monotherapy demonstrated insufficient oncologic outcomes in previously reported studies. To improve the clinical outcomes of unresectable huge HCC, combined locoregional treatments can be considered in selected cases. Here, we report a case of 58-year-old male patient who was treated with combined transarterial chemoembolization (TACE) and external beam radiotherapy for recurrent HCC after a previous hepatic resection. After combined TACE and radiotherapy for the intrahepatic lesion, two metastases were diagnosed in the pelvic bones and lung; each lesion was successfully treated with salvage radiotherapy. During the long-term follow-up period (around 8 years 7 months after combined TACE and radiotherapy for the recurrent huge HCC), no definite viable tumors were observed in any of the treated liver, bone, and lung lesions.

Expression of vascular endothelial growth factor as a predictor of complete response for preoperative chemoradiotherapy in rectal cancer.

Biomarkers that predict tumor response before surgical treatment are necessary to help select patients for preoperative chemoradiotherapy for rectal cancer. However, no definite predictive biomarker has been established. This study explored programmed death-ligand 1 (PD-L1), epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), p-signal transducer and activator of transcription 3 (p-STAT3), and death-domain associated protein as predictive biomarkers with regard to preoperative chemoradiotherapy in rectal cancer.Formalin-fixed paraffin-embedded cancer tissues from pretreatment biopsies from 31 patients who underwent preoperative chemoradiotherapy were studied. The biomarkers were evaluated by immunohistochemistry.PD-L1 positivity was found in 22.6% of 31 patients and complete response (CR) showed 33.3% and non-CR showed 18.2%. EGFR positivity was found in 71.0% of 31 patients and CR showed 88.9% and non-CR showed 73.6%. VEGF positivity was found in 83.9% of 31 patients and CR showed 88.9% and non-CR showed 81.8%. p-STAT3 positivity was found in 80.6% of 31 patients and CR showed 88.9% and non-CR showed 77.3%. On multiple logistic regression analysis, only VEGF expression was found to be a significant predictive factor for CR (P = .001). VEGF expression in pretreatment biopsies might be a predictive marker for CR after preoperative chemoradiation in rectal cancer.Although there is a restriction of small sample size, our finding suggested that this study can be foundation for a larger further study for biomarkers which can predict neoadjuvant therapy response of specimens obtained for diagnosis before surgery.

Gross tumor volume dependency on phase sorting methods of four-dimensional computed tomography images for lung cancer.

PURPOSE: To see the gross tumor volume (GTV) dependency according to the phase selection and reconstruction methods, we measured and analyzed the changes of tumor volume and motion at each phase in 20 cases with lung cancer patients who underwent image-guided radiotherapy. MATERIALS AND METHODS: We retrospectively analyzed four-dimensional computed tomography (4D-CT) images in 20 cases of 19 patients who underwent image-guided radiotherapy. The 4D-CT images were reconstructed by the maximum intensity projection (MIP) and the minimum intensity projection (Min-IP) method after sorting phase as 40%-60%, 30%-70%, and 0%-90%. We analyzed the relationship between the range of motion and the change of GTV according to the reconstruction method. RESULTS: The motion ranges of GTVs are statistically significant only for the tumor motion in craniocaudal direction. The discrepancies of GTV volume and motion between MIP and Min-IP increased rapidly as the wider ranges of duty cycles are selected. CONCLUSION: As narrow as possible duty cycle such as 40%-60% and MIP reconstruction was suitable for lung cancer if the respiration was stable. Selecting the reconstruction methods and duty cycle is important for small size and for large motion range tumors.

Comparison between audio-only and audiovisual biofeedback for regulating patients' respiration during four-dimensional radiotherapy.

PURPOSE: To compare audio-only biofeedback to conventional audiovisual biofeedback for regulating patients' respiration during four-dimensional radiotherapy, limiting damage to healthy surrounding tissues caused by organ movement. MATERIALS AND METHODS: Six healthy volunteers were assisted by audiovisual or audio-only biofeedback systems to regulate their respirations. Volunteers breathed through a mask developed for this study by following computer-generated guiding curves displayed on a screen, combined with instructional sounds. They then performed breathing following instructional sounds only. The guiding signals and the volunteers' respiratory signals were logged at 20 samples per second. RESULTS: The standard deviations between the guiding and respiratory curves for the audiovisual and audio-only biofeedback systems were 21.55% and 23.19%, respectively; the average correlation coefficients were 0.9778 and 0.9756, respectively. The regularities between audiovisual and audio-only biofeedback for six volunteers' respirations were same statistically from the paired t-test. CONCLUSION: The difference between the audiovisual and audio-only biofeedback methods was not significant. Audio-only biofeedback has many advantages, as patients do not require a mask and can quickly adapt to this method in the clinic.