Evidence-based clinical recommendations for hypofractionated radiotherapy: exploring efficacy and safety - Part 2. Lung (non-small cell lung cancer).

Several recent studies have investigated the use of hypofractionated radiotherapy (HFRT) for various cancers. However, HFRT for non-small cell lung cancer (NSCLC) with or without concurrent chemotherapy is not yet widely used because of concerns about serious side effects and the lack of evidence for improved treatment results. Investigations of HFRT with concurrent chemotherapy in NSCLC have usually been performed in single-arm studies and with a small number of patients, so there are not yet sufficient data. Therefore, the Korean Society for Radiation Oncology Practice Guidelines Committee planned this review article to summarize the evidence on HFRT so far and provide it to radiation oncology clinicians. In summary, HFRT has demonstrated promising results, and the reviewed data support its feasibility and comparable efficacy for the treatment of locally advanced NSCLC. The incidence and severity of esophageal toxicity have been identified as major concerns, particularly when treating large fraction sizes. Strategies, such as esophagus-sparing techniques, image guidance, and dose constraints, may help mitigate this problem and improve treatment tolerability. Continued research and clinical trials are essential to refine treatment strategies, identify optimal patient selection criteria, and enhance therapeutic outcomes.

Safety and Efficacy of HL301 In Radiation Pneumonitis in Patients With Unresectable Non-Small Cell Lung Cancer Receiving Curative Concurrent Chemoradiotherapy: A Multicenter, Randomized, Double-Blinded, Placebo-Controlled, Phase 2a Clinical Trial.

PURPOSE: We aimed to investigate the safety and efficacy of HL301, a standardized combination product of 7 medicinal plants, in radiation pneumonitis in patients with unresectable non-small cell lung cancer undergoing curative concurrent chemoradiotherapy. METHODS AND MATERIALS: The target accrual was 87 and a total of 63 patients were enrolled due to poor accrual rate. We randomly assigned the 63 patients to receive a placebo (arm A), or 1200 mg HL301 (arm B), or 1800 mg HL301 (arm C). Patients received weekly paclitaxel and carboplatin concurrently with intensity-modulated radiation therapy at 60 to 66 Gy in conventional fractionation. Durvalumab was administered as a maintenance treatment according to standard clinical practice. HL301 was administered orally, daily for 12 weeks. The primary endpoint was incidence of grade ≥2 radiation pneumonitis at 24 weeks postchemoradiotherapy. RESULTS: The baseline characteristics of the patients were well balanced. The drug was tolerable with a compliance rate of 86.6%, 86.2%, and 88.8% in arms A, B, and C, respectively (P = .874). None of the patients experienced severe drug-related adverse events. No significant difference in the rate of adverse events were observed between the treatment arms. The incidence of grade ≥2 radiation pneumonitis at 24 weeks postchemoradiotherapy was 37.5% (95% CI, 18.5%-61.4%), 55.6% (95% CI, 33.7%-75.4%), and 52.4% (95% CI, 32.4%-71.7%) in arms A, B, and C, respectively (P = .535). CONCLUSIONS: This is the first exploratory clinical trial to test the safety and efficacy of HL301 in patients with non-small cell lung cancer. Safety and feasibility of HL301 were established but no signals of efficacy in reducing radiation pneumonitis was observed in this dose level.

Evidence-based clinical recommendations for hypofractionated radiotherapy: exploring efficacy and safety - Part 1. Brain and head and neck.

Advances in radiotherapy (RT) techniques, including intensity-modulated RT and image-guided RT, have allowed hypofractionation, increasing the fraction size over the conventional dose of 1.8-2.0 Gy. Hypofractionation offers advantages such as shorter treatment times, improved compliance, and under specific conditions, particularly in tumors with a low α/ß ratio, higher efficacy. It was initially explored for use in RT for prostate cancer and adjuvant RT for breast cancer, and its application has been extended to various other malignancies. Hypofractionated RT (HFRT) may also be effective in patients who are unable to undergo conventional treatment owing to poor performance status, comorbidities, or old age. The treatment of brain tumors with HFRT is relatively common because brain stereotactic radiosurgery has been performed for over two decades. However, re-irradiation of recurrent lesions and treatment of elderly or frail patients are areas under investigation. HFRT for head and neck cancer has not been widely used because of concerns regarding late toxicity. Thus, we aimed to provide a comprehensive summary of the current evidence for HFRT for brain tumors and head and neck cancer and to offer practical recommendations to clinicians faced with the challenge of choosing new treatment options.

Diagnostic assessments and treatment results of well-differentiated gastric-type adenocarcinoma of the uterine cervix (Adenoma malignum): A multicenter retrospective analysis of KROG 22-03 study.

OBJECTIVE: Among cervical adenocarcinomas, well-differentiated gastric adenocarcinoma of the uterine cervix (WD-GAS), previously termed adenoma malignum (minimal deviation adenocarcinoma) is not well understood. Because of its rarity and difficulty in diagnosis, there is no standard care for WD-GAS. Thus, we conducted the first multicenter retrospective study on WD-GAS to clarify prognostic factors for long-term survival and recurrence. METHODS: Patients diagnosed with WD-GAS at eight hospitals participated in this multi-center study. Overall survival (OS) and recurrence-free survival (RFS) were calculated with the Kaplan-Meier method. Additionally, OS between the early and advanced FIGO stage groups were compared with the log-rank test. Cox regression analysis was conducted to identify significant factors associated with recurrence-free survival (RFS). RESULTS: A total of 73 patients from eight hospitals in South Korea were included in the analysis. The median follow-up period was 44.8 months, and all patients underwent curative surgical intervention as the primary treatment. Recurrence was observed in 17 patients (23.3%). Ten patients had locoregional recurrence, four patients had distant metastasis, and three patients presented with both locoregional recurrence and distant metastasis. The Cox regression analysis identified several statistically significant factors associated with RFS, including vaginal invasion (VI), parametrial invasion (PMI), resection margin (RM), and nodal and lymphovascular invasion (LVI). When considering these five factors together, patients without any of the factors exhibited recurrence-free survival (RFS) of 97.0% at three years and those with more than one of these factors had a 3-year RFS of 65.4% (P < 0.001). CONCLUSION: WD-GAS showed relatively high locoregional recurrence rate. Positive PMI, VI, RM, nodal involvement, and LVI were associated with a significant increase in recurrence or distant metastasis rates.

When Should Spinal Surgery Be Considered for Spinal Metastasis from Non-Small Cell Lung Cancer?-Propensity Score Matched Study between Surgery with Radiotherapy and Radiotherapy Alone.

(1) Background: Although metastatic spine disease is increasing, the debate on therapeutic modality remains due to the heterogeneity of tumors and patients. This study aims to evaluate the efficacies of surgery and risk factors for patients' survival from potentially unstable spinal metastasis of non-small cell lung cancer; (2) Methods: Twenty-two patients undergoing surgery and radiotherapy (group I) were compared with 22 patients undergoing radiotherapy alone (group II) using propensity score matching in a 1-to-1 format. Clinical outcomes included the performance status and ambulatory status. In addition, independent risk factors for patients' survival were evaluated, including the molecular targeted therapy for mutations; (3) Results: deterioration in neurologic status was only observed in group II compared to group I (22.7% vs. 0%, p-value = 0.018). In addition, five patients in the surgery group showed improved Frankel grades. Regarding the patients' survival, a smoking history of more than ten pack-years (hazard ratio (HR) = 12.18), worse performance status (HR = 6.86), and absence of mutations (HR = 3.39) were the independent risk factors; (4) Conclusions: Spinal surgery with radiotherapy could have advantages for improving the neurologic status including ambulation for potentially unstable spine due to metastasis. Thus, surgery should be considered for patients with a longer life expectancy resulting from better performance status and use of the targeted therapy.

The Updated World Health Organization Classification Better Predicts Survival in Patients With Endocervical Adenocarcinoma (KROG 20-07).

PURPOSE: The 2020 World Health Organization classification divided endocervical adenocarcinoma (ADC) into human papillomavirus-associated (HPVA) and human papillomavirus-independent (HPVI) ADCs. This multi-institutional study aimed to investigate the clinical features and prognosis of patients with endocervical ADC based on the updated World Health Organization classification. METHODS AND MATERIALS: We retrospectively reviewed the 365 patients with endocervical ADC who underwent radical hysterectomy from 7 institutions. Tumor characteristics, patterns of failure, and survival outcomes were compared between HPVA and HPVI ADCs. RESULTS: Two hundred seventy-five (75.3%) and 90 (24.7%) patients had HPVA and HPVI ADC diagnoses, respectively. In all cases, the 5-year disease-free survival (DFS) and overall survival (OS) rates were 58.2% and 71.3%, respectively. HPVI ADC showed higher rates of local recurrence (25.6% vs 10.9%) and distant metastasis (33.3% vs 17.5%) than HPVA ADC. Multivariate survival analysis revealed that HPVI ADC showed significantly worse DFS (hazard ratio [HR], 1.919; 95% confidence interval [CI], 1.324-2.781; P < .001), distant metastasis-free survival (HR, 2.100; 95% CI, 1.397-3.156; P < .001), and OS (HR, 2.481; 95% CI, 1.586-3.881; P < .001) than HPVA ADC. Patients with gastric- and serous-type HPVI ADC had significantly worse OS than those with other HPVI ADCs (P = .020). Similarly, invasive stratified mucin-producing-type HPVA ADC showed significantly worse OS than other HPVA ADCs (P < .001). CONCLUSIONS: We demonstrated that HPVI ADC exhibited inferior DFS and OS and higher rates of local and distant recurrence compared with HPVA ADC. Gastric- and serous-type HPVI ADCs and invasive stratified mucin-producing-type HPVA ADC showed worse OS than other types of HPVI and HPVA ADCs, respectively. Our observation of significant differences in prognoses according to the histologic types needs to be validated in larger cohorts of patients with endocervical ADC.

Current Evidence of a Deintensification Strategy for Patients with HPV-Related Oropharyngeal Cancer.

Human papillomavirus (HPV)-related oropharyngeal cancer differs from HPV-negative oropharyngeal cancer in terms of etiology, epidemiology, and prognosis. Younger and lower comorbidity patient demographics and favorable prognosis allow HPV-related oropharyngeal cancer patients to anticipate longer life expectancy. Reducing long-term toxicities has become an increasingly important issue. Treatment deintensification to reduce toxicities has been investigated in terms of many aspects, and the reduction of radiotherapy (RT) dose in definitive treatment, replacement of platinum-based chemotherapy with cetuximab, response-tailored dose prescription after induction chemotherapy, and reduction of adjuvant RT dose after transoral surgery have been evaluated. We performed a literature review of prospective trials of deintensification for HPV-related oropharyngeal cancer. In phase II trials, reduction of RT dose in definitive treatment showed comparable survival outcomes to historical results. Two phase III randomized trials reported inferior survival outcomes for cetuximab-based chemoradiation compared with cisplatin-based chemoradiation. In a randomized phase III trial investigating adjuvant RT, deintensified RT showed noninferior survival outcomes in patients without extranodal extension but worse survival in patients with extranodal extension. Optimal RT dosage and patient selection require confirmation in future studies. Although many phase II trials have reported promising outcomes, the results of phase III trials are needed to change the standard treatment. Since high-level evidence has not been established, current deintensification should only be performed as part of a clinical study with caution. Implementation in clinical practice should not be undertaken until evidence from phase III randomized trials is available.

Importance of lymph node ratio in HPV-related oropharyngeal cancer patients treated with surgery and adjuvant treatment.

OBJECTIVES: The pathologic nodal stage of human papillomavirus (HPV)-related oropharyngeal cancer (OPC) patients is classified according to the number of lymph nodes (LNs), as revised in 2018. Previous studies showed that the LN ratio (LNR) could be also a significant prognostic factor in head and neck cancer, but there are few studies on the LNR in HPV-related [HPV(+)] OPC. The aim of the present study was to analyze the predictive value of the LNR for survival and recurrence in HPV(+) OPC patients. MATERIALS AND METHODS: HPV(+) OPC patients treated with surgery with or without postoperative radiotherapy from January 2000 to March 2019 were evaluated. The patients were divided into two sets of three groups, according to LN numbers based on pathologic nodal stages, and LNRs by a cutoff value of 0.05. The medical records were reviewed, and the overall survival (OS), disease-free survival, locoregional recurrence, and distant metastasis incidence were analyzed. RESULTS: Ninty patients were included and the median follow-up period was 38.2 months. There were no significant differences in OS in the LN number groups. However, there was a significant difference in OS in the LNR groups (P = 0.010). The incidence of distant metastasis in the LNR groups was significantly different (P = 0.005). CONCLUSION: The LNR in HPV(+) OPC patients may be a more useful tool to predict survival and distant metastasis than the LN number. Additional research and consensus on surgical pathology are needed before applying the LNR to adjuvant treatment decisions and pathologic nodal staging.

Oncologic outcomes according to the level of disease burden in patients with metachronous distant metastases from uterine cervical cancer: a Korean Radiation Oncology Group study (KROG 18-10).

OBJECTIVE: This study aimed to evaluate the oncologic outcomes according to disease burden in uterine cervical cancer patients with metachronous distant metastases. METHODS: Between 2005 and 2015, 163 patients with metachronous distant metastases from uterine cervical cancer after receiving a definitive therapy were evaluated at seven institutions in Korea. Low metastatic burden was defined as less than 5 metastatic sites, whereas high metastatic burden was others. Each metastasis site was divided based on the lymph node (LN) and organs affected. The overall survival (OS) and progression-free survival (PFS) were assessed. Cox proportional hazards models, including other clinical variables, were used to evaluate the survival outcomes. RESULTS: The median follow-up duration was 22.2 months (range: 0.3-174.8 months). Para-aortic LNs (56.4%), lungs (26.4%), supraclavicular LNs (18.4%), and peritoneum (13.5%) were found to be the common metastasis sites. Among 37 patients with a single metastasis, 17 (45.9%) had LN metastases and 20 (54.1%) had organ metastases. The 1- and 2-year OS rates were 73.9% and 55.0%, respectively, whereas the PFS rates were 67.2% and 42.9%, respectively. SCC Ag after recurrence and high metastatic burden were significant factors affecting the OS (p=0.004 and p<0.001, respectively). Distant organ recurrence, short disease-free interval (≤2 years), and high metastatic burden were unfavorable factors for PFS (p=0.003, p=0.011, and p=0.002, respectively). CONCLUSION: A favorable oncologic outcome can be expected by performing salvage treatments in selected patients with a long disease-free interval, low metastatic burden, and/or lymphatic-only metastasis.

Comparison of treatment outcomes of pelvis external radiotherapy with and without vaginal brachytherapy for cervical cancer patients with positive or close vaginal resected margins.

BACKGROUND: We evaluated whether there is a difference in the local recurrence and survival after pelvic external radiotherapy (ERT) with and without boost vaginal brachytherapy (VB) in cervical cancer patients with positive or close vaginal resected margins (RM). METHODS: We retrospectively reviewed FIGO stage IA-IIB cervical cancer patients treated with postoperative ERT between 1997 and 2018. The sixty patients showing close (safety margin < 5 mm) or positive vaginal RM were included. ERT was delivered with median 50.4 Gy in 28 fractions to the pelvis and VB with median 30 Gy in 6 fractions. RESULTS: The median follow-up duration was 46 months. Five out of 30 patients treated with ERT alone experienced vaginal recurrence within 2 years after surgery. The 5-year local control (LC) was 100% in patients receiving ERT + VB compared with 81.3% in patients receiving ERT alone (log rank p = 0.022). The 5-year pelvic control (PC) was 95.8% for patients receiving ERT + VB and 76.8% for ERT alone (p = 0.041). The 5-year overall survival and recurrence-free survival (RFS) were not significantly different between treatment groups. In multivariate analysis, perineural invasion was a significant risk factor for PC (p = 0.024). Parametrial involvement (p = 0.044) and vascular invasion (p = 0.032) were unfavorable prognostic factors for RFS. Late toxicity occurrences were not significant in both groups. CONCLUSION: VB after ERT improved LC and PC in cervical cancer patients with close or positive RM after hysterectomy. The toxicities were not increased after VB was added to ERT.

Survey of radiation field and dose in human papillomavirus-positive oropharyngeal cancer: is de-escalation actually applied in clinical practice?

PURPOSE: Studies on de-escalation in radiation therapy (RT) for human papillomavirus-related (HPV(+)) oropharyngeal cancer (OPC) are currently ongoing. This study investigated the current practice regarding the radiation dose and field in the treatment of HPV(+) OPC. MATERIALS AND METHODS: The Korean Society for Head and Neck Oncology conducted a questionnaire on the primary treatment policy. Among them, for HPV(+) OPC scenarios, radiation oncologists were questioned regarding the field and dose of RT. RESULTS: Forty-two radiation oncologists responded to the survey. In definitive concurrent chemoradiotherapy (CCRT) treatment for stage T2N1M0 OPC, most respondents prescribed a dose of >60 Gy to the primary tonsil and involved ipsilateral lymph nodes. However, eight of the respondents prescribed a relatively low dose of ≤54 Gy. For stage T2N1M0 OPC, postoperative adjuvant RT was prescribed by eight and nine respondents with a lower dose of ≤50 Gy for the ipsilateral tonsil and involved neck, respectively. In definitive CCRT in complete remission after induction chemotherapy for initial stage T2N3M0 OPC, de-escalation of the tonsil and involved neck were performed by eight and seven respondents, respectively. Regarding whether de-escalation is applied in radiotherapy for HPV(+) OPC, 27 (64.3%) did not do it at present, and 15 (35.7%) were doing or considering it. CONCLUSION: The field and dose of prescribed treatment varied between institutions in Korea. Among them, dose de-escalation of RT in HPV(+) OPC was observed in approximately 20% of the respondents. Consensus guidelines will be set in the near future after the completion of ongoing prospective trials.

Serum conversion pattern of SCC-Ag levels between pre- and post-chemoradiotherapy predicts recurrence and metastasis in cervical cancer: a multi-institutional analysis.

The value of squamous-cell carcinoma antigen (SCC-Ag) as a tumor marker for cervical cancer is controversial because it is not elevated (> 2 ng/mL) in a quarter of patients at diagnosis. Two hundred ninety one IB-IVA cervical squamous cell-carcinoma patients who underwent definitive chemoradiotherapy (CRT) were included in four tertiary institutions. Serum conversion pattern between pre- and post-treatment SCC-Ag levels was categorized into the following three arms: (1) Consistent Seronegative arm (both ≤ 2 ng/mL); (2) Negative Conversion arm (from > 2 ng/mL to ≤ 2 ng/mL); and (3) Consistent Seropositive arm (both > 2 ng/mL). Median follow-up time was 40.3 months. For Consistent Seronegative (N = 67), Negative Conversion (N = 165), and Consistent Seropositive (N = 59) arms, the 3-year recurrence-free survival (RFS) rates were 79.4%, 62.0%, and 48.4% (P < 0.001) and the 3-year overall survival (OS) rates were 86.3%, 80.6%, and 58.7% (P = 0.001), respectively. The serum conversion pattern of SCC-Ag between pre- and post-treatment was the most significant and potent prognostic factor of RFS (P = 0.001) and OS (P = 0.007) on the multivariate analysis. Simply checking whether SCC-Ag level is above or below 2 ng/mL before and after definitive CRT can provide clinicians with a simple rule-of-thumb for prediction of disease outcome in cervical cancer patients.

Early risk-assessment of patients with nasopharyngeal carcinoma: the added prognostic value of MR-based radiomics.

OBJECTIVES: To assess the additive prognostic value of MR-based radiomics in predicting progression-free survival (PFS) in patients with nasopharyngeal carcinoma (NPC) METHODS: Patients newly diagnosed with non-metastatic NPC between June 2006 and October 2019 were retrospectively included and randomly grouped into training and test cohorts (7:3 ratio). Radiomic features (n=213) were extracted from T2-weighted and contrast-enhanced T1-weighted MRI. The patients were staged according to the 8th edition of American Joint Committee on Cancer Staging Manual. The least absolute shrinkage and selection operator was used to select the relevant radiomic features. Univariate and multivariate Cox proportional hazards analyses were conducted for PFS, yielding three different survival models (clinical, stage, and radiomic). The integrated time-dependent area under the curve (iAUC) for PFS was calculated and compared among different combinations of survival models, and the analysis of variance was used to compare the survival models. The prognostic performance of all models was validated using a test set with integrated Brier scores. RESULTS: This study included 81 patients (training cohort=57; test cohort=24), and the mean PFS was 57.5 ± 43.6 months. In the training cohort, the prognostic performances of survival models improved significantly with the addition of radiomics to the clinical (iAUC, 0.72-0.80; p=0.04), stage (iAUC, 0.70-0.79; p=0.001), and combined models (iAUC, 0.76-0.81; p<0.001). In the test cohort, the radiomics and combined survival models were robustly validated for their ability to predict PFS. CONCLUSION: Integration of MR-based radiomic features with clinical and stage variables improved the prediction PFS in patients diagnosed with NPC.

Analysis of PET parameters as prognosticators of survival and tumor extent in Oropharyngeal Cancer treated with surgery and postoperative radiotherapy.

BACKGROUND: Positron-emission tomography (PET) is widely used to detect malignancies, but consensus on its prognostic value in oropharyngeal cancer has not been established. The purpose of this study was to analyze the PET parameters associated with tumor extent and survival in resectable oropharyngeal cancer. METHODS: The PET parameters in oropharyngeal cancer patients with regional node metastasis who underwent surgery and postoperative radiotherapy between January 2005 and January 2019 were analyzed. We calculated the SUVmax, tumor-to-liver ratio (TLR), metabolic tumor volume (MTV, volume over SUV 2.5), and total lesion glycolysis (TLG, MTV x mean SUV) of the primary lesion and metastatic nodes. Histologic findings, patient survival, and recurrence were reviewed in the medical records. RESULTS: Fifty patients were included, and the PET parameters were extracted for 50 primary lesions and 104 nodal lesions. In the survival analysis, MTV and TLG of the primary lesions showed significant differences in overall survival (OS) and recurrence-free survival (RFS). In the multiple regression analysis, TLG of the primary lesion was associated with the depth of invasion (DOI). MTV of the nodes was a significant factor affecting extranodal extension (ENE). CONCLUSIONS: PET parameters could be related with OS, RFS, DOI of the primary tumor, and ENE. PET would be expected to be a useful diagnostic tool as a prognosticator of survival and pathologic findings in oropharyngeal cancer.

Recent Treatment Patterns of Oropharyngeal Cancer in Korea Based on the Expert Questionnaire Survey of the Korean Society for Head and Neck Oncology (KSHNO).

PURPOSE: The incidence of human papillomavirus (HPV)-related oropharyngeal cancer (OPC) has increased, and staging and optimal therapeutic approaches are challenging. A questionnaire survey was conducted to investigate the controversial treatment policy of stage T2 OPC according to the N category and determine the opinions of multidisciplinary experts in Korea. MATERIALS AND METHODS: Five OPC scenarios were developed by the Subcommittee on Oropharyngeal Treatment Guidelines of the Korean Society for Head and Neck Oncology and distributed to experts of multidisciplinary treatment hospitals. RESULTS: Sixty-five experts from 45 institutions responded. For the HPV-positive T2N0M0 scenario, 67.7% of respondents selected surgery followed by definitive concurrent chemoradiotherapy (CCRT) or radiotherapy alone. For the T2N1M0 HPV-positive scenario, there was a notable difference in the selection of primary treatment by expert specialty; 53.9% of respondents selected surgery and 39.8% selected definitive CCRT as the primary treatment. For the T2N3M0 advanced HPV-positive scenario, 50.0% of respondents selected CCRT and 33.3% considered induction chemotherapy (IC) as the primary treatment. CCRT and IC were significantly more frequently selected for the HPV-related OPC cases (p=0.010). The interdepartmental variability showed that the head and neck surgeons and medical oncologists favored surgery, whereas the radiation oncologists preferably selected definitive CCRT (p < 0.001). CONCLUSION: In this study, surgery was preferred for lymph node-negative OPC, and as lymph node metastasis progressed, CCRT tended to be preferred, and IC was administered. Clinical practice patterns by stage and HPV status showed differences according to expert specialty. Multidisciplinary consensus guidelines will be essential in the future.

The effect of adjuvant chemotherapy and early tumor regression on the outcome of nasopharyngeal cancer patients treated with concurrent chemoradiotherapy.

OBJECTIVES: We assessed the role of adjuvant chemotherapy (ACT) in patients with advanced nasopharyngeal carcinoma treated with concurrent chemoradiotherapy (CCRT) and investigated the prognostic factors for recurrence and survival. MATERIALS AND METHODS: Between January 2008 and January 2018, 88 non-metastatic nasopharyngeal carcinoma patients treated with CCRT and with or without ACT in two institutions were retrospectively reviewed. The initial tumor response evaluation was performed 1 month after CCRT completion. Survival analysis was performed for factors such as initial tumor regression, ACT and other clinical factors. Subgroup analysis was performed for the four-group categorized according to tumor regression and ACT (CR with/without ACT, non-CR with/without ACT). RESULTS: Complete response (CR) 1 month after CCRT was a favorable prognosticator for progression-free survival (PFS) (hazard ratio [HR] 3.16, 95% confidence interval [CI] 1.02-9.85, p = 0.046) and overall survival (OS) (HR 3.19, 95% CI 1.14-8.93, p = 0.027). Also, ACT was an independent factor for PFS (HR 0.38, 95% CI 0.15-0.98, p = 0.047) and OS (HR 0.37, 95% CI 0.13-0.99, p = 0.047). In subgroup analysis, the CR after CCRT followed by ACT group showed significantly higher locoregional recurrence-free survival (p = 0.02), OS (p = 0.003), distant-metastasis free survival (p = 0.07), and PFS (p = 0.01) than the other three groups. CONCLUSION: Tumor regression 1 month after CCRT, and administration of ACT identified as an independent prognosticator for PFS and OS in this study. Even patients who show early tumor regression after CCRT may benefit from ACT. Further randomized trials should define the role of ACT in patients with nasopharyngeal cancer who achieved CR after CCRT.

Anti-tumor efficacy of CKD-516 in combination with radiation in xenograft mouse model of lung squamous cell carcinoma.

BACKGROUND: Hypoxic tumors are known to be highly resistant to radiotherapy and cause poor prognosis in non-small cell lung cancer (NSCLC) patients. CKD-516, a novel vascular disrupting agent (VDA), mainly affects blood vessels in the central area of the tumor and blocks tubulin polymerization, thereby destroying the aberrant tumor vasculature with a rapid decrease in blood, resulting in rapid tumor cell death. Therefore, we evaluated the anti-tumor efficacy of CKD-516 in combination with irradiation (IR) and examined tumor necrosis, delayed tumor growth, and expression of proteins involved in hypoxia and angiogenesis in this study. METHODS: A xenograft mouse model of lung squamous cell carcinoma was established, and the tumor was exposed to IR 5 days per week. CKD-516 was administered with two treatment schedules (day 1 or days 1 and 5) 1 h after IR. After treatment, tumor tissues were stained with hematoxylin and eosin, and pimonidazole. HIF-1α, Glut-1, VEGF, CD31, and Ki-67 expression levels were evaluated using immunohistochemical staining. RESULTS: Short-term treatment with IR alone and CKD-516 + IR (d1) significantly reduced tumor volume (p = 0.006 and p = 0.048, respectively). Treatment with CKD-516 + IR (d1 and d1, 5) resulted in a marked reduction in the number of blood vessels (p < 0.005). More specifically, CKD-516 + IR (d1) caused the most extensive tumor necrosis, which resulted in a significantly large hypoxic area (p = 0.02) and decreased HIF-1α, Glut-1, VEGF, and Ki-67 expression. Long-term administration of CKD-516 + IR reduced tumor volume and delayed tumor growth. This combination also greatly reduced the number of blood vessels (p = 0.0006) and significantly enhanced tumor necrosis (p = 0.004). CKD-516 + IR significantly increased HIF-1α expression (p = 0.0047), but significantly reduced VEGF expression (p = 0.0046). CONCLUSIONS: Taken together, our data show that when used in combination, CKD-516 and IR can significantly enhance anti-tumor efficacy compared to monotherapy in lung cancer xenograft mice.

Intensity-Modulated Radiotherapy-Based Reirradiation for Head and Neck Cancer: A Multi-institutional Study by Korean Radiation Oncology Group (KROG 1707).

PURPOSE: The benefits of reirradiation for head and neck cancer (HNC) have not been determined. This study evaluated the efficacy of reirradiation using intensity-modulated radiotherapy (IMRT) for recurrent or second primary HNC (RSPHNC) and identified subgroups for whom reirradiation for RSPHNC is beneficial. MATERIALS AND METHODS: A total of 118 patients from seven Korean institutions with RSPHNC who underwent IMRT-based reirradiation between 2006 and 2015 were evaluated through retrospective review of medical records. We assessed overall survival (OS) and local control (LC) within the radiotherapy (RT) field following IMRT-based reirradiation. Additionally, the OS curve according to the recursive partitioning analysis (RPA) suggested by the Multi-Institution Reirradiation (MIRI) Collaborative was determined. RESULTS: At a median follow-up period of 18.5 months, OS at 2 years was 43.1%. In multivariate analysis, primary subsite, recurrent tumor size, interval between RT courses, and salvage surgery were associated with OS. With regard to the MIRI RPA model, the class I subgroup had a significantly higher OS than class II or III subgroups. LC at 2 years was 53.5%. Multivariate analyses revealed that both intervals between RT courses and salvage surgery were prognostic factors affecting LC. Grade 3 or more toxicity and grade 5 toxicity rates were 8.5% and 0.8%, respectively. CONCLUSION: IMRT-based reirradiation was an effective therapeutic option for patients with RSPHNC, especially those with resectable tumors and a long interval between RT courses. Further, our patients' population validated the MIRI RPA classification by showing the difference of OS according to MIRI RPA class.

Prognostic value of computed tomography-based volumetric body composition analysis in patients with head and neck cancer: Feasibility study.

BACKGROUND: This study aimed to evaluate whether computed tomography (CT)-based volumetric body composition analysis has prognostic value in head and neck cancer (HNC) patients. METHODS: This single-center retrospective study included 79 patients with HNC treated with definitive radiotherapy from March 2009 to December 2018. The patients were assessed for (a) weight-based variables and (b) pretreatment and posttreatment CT-based body composition variables. Overall survival (OS) and recurrence-free survival (RFS) analyses were conducted using Cox proportional hazards analyses. RESULTS: Depletion of cervical skeletal muscle volume on presentation was associated with poor OS (hazard ratio [HR] = 3.1; 95% CI = 1.2-7.8; P = .016). Low fat proportions before and after treatment were associated with poor OS (HR = 2.5-3.5; 95% CI = 1.3-9.3; P = .013-.026). In multivariate Cox analysis, increased posttreatment fat attenuation demonstrated the greatest prognostic value for both OS (HR = 4.7; 95% CI = 2.2-10.3; P < .001) and RFS (HR = 4.3; 95% CI = 2.0-9.5; P < .001). CONCLUSIONS: CT-based body composition analysis has the potential for risk assessment in patients with HNC.

Upfront radiosurgery plus targeted agents followed by active brain control using radiosurgery delays neurological death in non-small cell lung cancer with brain metastasis.

The role of radiosurgery has become further accentuated in the era of targeted agents (TA). Thus, the neurologic outcome of radiosurgery in brain metastasis (BM) of non-small cell lung cancer (NSCLC) was reviewed. We analyzed 135 patients with BM of NSCLC who were administered Cyberknife radiosurgery (CKRS) as either initial or salvage therapy. We evaluated local failure (LF), intracranial failure (IF), and neurological death (ND) due to BM. Primary outcome was neurological death-free survival (NDFS). Median follow-up was 16.2 months. Median CKRS dose of 22 Gy was administered to median 2 targets per patient. Among 99 deaths, 14 (14%) were ND. Upfront treatment for BM included CKRS alone in 85 patients (63%), CKRS + TA in 26 patients (19%), and WBRT in 24 patients (18%). No patients or tumor related factors were associated with ND. However, the type of upfront treatment for BM was significantly associated with ND [HR 0.07 (95% CI 0.01-0.57) for CKRS + TA, HR 0.56 (95% CI 0.19-1.68) for CKRS alone] compared with the WBRT group (P = 0.01). The 2-year NDFS rates for the CKRS + TA, CRKS alone, and WBRT groups were 94%, 87%, and 78%, respectively (P = 0.03). Upfront CKRS showed significantly higher 2-year LF-free survival rate (P < 0.01). IF rate was insignificantly lower in the WBRT group compared with CKRS group (P = 0.38). Upfront CKRS + TA was associated with the best neurological outcome with high NDFS. Active brain control by early delivery of radiosurgery could achieve better neurological outcome in NSCLC with BM.