Effect of Interstitial Lung Abnormality on Concurrent Chemoradiotherapy-treated Stage III Non-small Cell Lung Cancer Patients.

BACKGROUND/AIM: Pre-treatment interstitial lung abnormality (ILA) is associated with post-cancer treatment adverse events and high mortality rate in lung cancer patients. This study aimed to assess whether ILA affects the survival and development of symptomatic radiation pneumonitis (RP) in unresectable stage III non-small cell lung cancer (NSCLC) patients who had undergone definitive concurrent chemoradiotherapy (CCRT). PATIENTS AND METHODS: Data of stage III NSCLC patients who underwent definitive CCRT between January 2010 and November 2017 were retrospectively collected. Univariate and multivariate regression analyses were performed to evaluate the risk factors for symptomatic RP. The association between pre-treatment ILA and survival was assessed using Kaplan-Meier analysis with log-rank test and Cox proportional hazards regression. RESULTS: This study included 201 patients (188 men) of a mean age of 64.7±7.3 years. Pre-treatment ILA and fibrotic ILA were observed in 21.9% and 12.9% of the patients, respectively. Symptomatic RP (grade ≥2) occurred in 13.5% of the patients. Fibrotic ILA was a significant risk factor for grade ≥2 RP and grade ≥3 RP (p=0.004 and 0.033, respectively). The survival rate was significantly poorer in patients with fibrotic ILA than in those without ILA. Cox proportional hazards regression revealed that fibrotic ILA was an independent risk factor for mortality (p<0.001). CONCLUSION: Pre-treatment fibrotic ILA is significantly associated with symptomatic RP and poor survival in unresectable stage III NSCLC patients who have undergone definitive CCRT. CCRT should be cautiously performed in patients presenting pre-treatment fibrotic ILA to prevent adverse outcomes.

Efficacy of hypofractionated preoperative chemoradiotherapy in rectal cancer.

The efficacy and toxicity of hypofractionated preoperative chemoradiotherapy (HPCRT) combined with oral capecitabine was evaluated in patients with rectal cancer. HPCRT was delivered by intensity-modulated radiotherapy of either 33 Gy to the whole pelvis or 35 Gy in 10 fractions to the primary tumor and 33 Gy to the surrounding pelvis. Surgery was performed 4-8 weeks after HPCRT completion. Oral capecitabine was administered concurrently. A total of 76 patients were eligible for this study, and patient numbers in clinical stages I, II, III and IVA were 5, 29, 36 and 6, respectively. Tumor response, toxicity and survival were analyzed. A total of 9/76 patients (11.8%) achieved a pathological complete response. Sphincter preservation was achieved in 23/32 (71.9%) and 44/44 (100%) of patients with a distal extent from the anal verge of ≤5 and >5 cm, respectively. A total of 28/76 patients (36.8%) achieved tumor-downstaging and 25/76 (32.9%) achieved nodal (N)-downstaging. The 5-year disease-free survival (DFS) and overall survival rates were 76.5% and 90.6%, respectively. In the multivariate analysis for DFS, pathological N stage and lymphovascular space invasion were notable prognostic factors. A total of 6 patients in stage IVA underwent salvage treatments for lung or liver metastasis after HPCRT completion, and all 6 were alive at the last follow-up. Only 4 patients experienced grade 3 postoperative complications. No grade 4 toxicities were observed. HPCRT of 33 or 35 Gy in 10 fractions showed similar results to those of long-course fractionation. This fractionation scheme could be beneficial for patients with early stage disease, locally advanced rectal cancer, simultaneous distant metastasis requiring early intervention or for patients who wish to avoid multiple hospital visits.

Definitive radiotherapy in patients with clinical T1N0M0 esophageal squamous cell carcinoma: A multicenter retrospective study (KROG 21-10).

PURPOSE: To assess the failure pattern and analyze the treatment scheme of definitive radiation therapy (RT) for T1N0M0 esophageal squamous cell carcinoma (ESCC). METHODS: We performed a multi-institutional retrospective analysis in T1N0M0 ESCC patients who underwent definitive RT from 2010 to 2019. Patterns of failure were demonstrated as in-, and out-field locoregional, and distant metastasis. In the analysis, freedom-from locoregional recurrence (FFLRR) and their association with clinicopathologic factors were evaluated. Propensity score matching in cT1b patients was done. RESULTS: 168 patients were included with a median follow-up of 34.0 months, and 26 cT1a, 116 cT1b disease. The rates of 3-year all and locoregional recurrence for cT1a were 30.5% and 24.1% and those for cT1b were 27.1% and 25.9%, respectively. Among 116 cT1b patients, 69 patients received elective nodal irradiation (ENI) and 47 received involved field irradiation (IFI). After propensity score matching, the 3-year FFLRR rate was 84.5%. There was no difference between ENI and IFI in FFLRR (P = 0.831) and OS (P = 0.525). The 3-year FFLRR was 83.8% (95% Confidence interval (CI), 61.8-93.8%) in IFI group and 85.3% (95% CI, 65.1-94.3%) in ENI group. In multivariate analysis, concurrent chemotherapy use was marginally associated with FFLRR (Hazard ratio, 0.16; P = 0.064). CONCLUSION: cT1a patients who cannot receive endoscopic resection showed similar failure rates as cT1b patients, questioning the staging accuracy and raised the need for thorough treatment like chemoradiotherapy. In cT1b patients, IFI with 50 to 60 Gy and concurrent chemotherapy could be reasonable.

PIVKA-II as a surrogate marker for prognosis in patients with localized hepatocellular carcinoma receiving stereotactic body radiotherapy.

PURPOSE: This study aimed to determine the correlation between protein induced by vitamin K absence or antagonist-II (PIVKA-II) and stereotactic body radiotherapy (SBRT) in patients with hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Sixty-one patients received SBRT between 2015 and 2020 with a median dose of 48 Gy (range, 39 to 60 Gy) with a median of 4 fractions. Changes in tumor markers before and after SBRT were analyzed. RESULTS: The median follow-up period was 31 months (range, 12 to 64 months). The estimated 2-year in-field failure-free survival, progression-free survival (PFS), and overall survival rates were 82.0%, 39.3%, and 96.7%, respectively. Patients with decreased PIVKA-II levels through SBRT had significantly few in-field failures (p = 0.005). Patients with PIVKA-II levels of ≤25 mAU/mL after SBRT had significantly long PFS (p = 0.004). CONCLUSION: PIVKA-II could be a useful surrogate marker for response or survival outcomes in patients with localized HCC receiving SBRT.

Clinical Outcome and Risk Factors of Chronic Radiation Proctitis Following Pelvic Radiation Therapy.

BACKGROUND/AIM: Pelvic radiation therapy (RT) is a common treatment for malignancies, including gynecological, genitourinary, and lower gastrointestinal tract cancers. However, chronic radiation proctitis (RP) is an unavoidable side effect, and its clinical presentation varies from asymptomatic to potentially life-threatening. This study evaluated the clinical characteristics and risk factors of chronic RP. PATIENTS AND METHODS: Patients with chronic RP (212) following RT for various pelvic cancers between January 2015 and December 2021 were enrolled. Clinical characteristics of RP were analyzed retrospectively. Severity was graded according to the Radiation Therapy Oncology Group (RTOG) modified rectal toxicity score and Vienna rectoscopy score (VRS), and risk factors were statistically analyzed. RESULTS: The most common pelvic cancer observed was cervical cancer. The patients received three-dimensional conformal RT (3D-CRT), intensity-modulated RT, or a combination of 3D-CRT and intracavitary RT (ICR). Rectal bleeding occurred in 70 (33.0%) patients. Previous abdominopelvic surgery and total radiation dose significantly correlated with the RTOG score and VRS. Previous abdominopelvic surgery, ICR, and total radiation dose were associated with chronic hemorrhagic RP. All patients with chronic hemorrhagic RP were treated with argon plasma coagulation (APC). 91.4% of cases required 1-3 APC sessions to resolve the bleeding, with a mean of 1.7 sessions. CONCLUSION: Our results showed that previous abdominopelvic surgery and total radiation dose were significant risk factors related to chronic RP, while total radiation dose was related to chronic hemorrhagic RP. We also showed that APC was effective and safe for chronic hemorrhagic RP.

Favorable prognosis of patients who received adjuvant androgen deprivation therapy after radiotherapy achieving undetectable levels of prostate-specific antigen in high- or very high-risk prostate cancer.

INTRODUCTION: To determine the prognostic significance of long-term adjuvant androgen deprivation therapy (A-ADT) over 1 year in achieving undetectable levels of prostate-specific antigen (PSA) less than 0.001 ng/mL in prostate cancer patients with high- or very high-risk prostate cancer who underwent radiotherapy (RT). MATERIALS AND METHODS: A total of 197 patients with prostate cancer received RT, with a follow-up of ≥12 months. Biochemical failure was defined as PSA ≥nadir + 2 ng/mL after RT. We analyzed clinical outcomes, including survival, failure patterns, and prognostic factors affecting outcomes. RESULTS: Biochemical failure-free survival (BCFFS), clinical failure-free survival, distant metastasis-free survival, cancer-specific survival, and overall survival (OS) rates at 5 years were 91.1%, 95.4%, 96.9%, 99.5%, and 89.1%, respectively. Administration of long-term A-ADT significantly predicted favorable BCFFS (p = 0.027) and OS (p < 0.001) in multivariate analysis. Nadir PSA ≤0.001 ng/mL was an independent prognostic factor for BCFFS (p = 0.006) and OS (p = 0.021). The use of long-term A-ADT significantly affected nadir PSA ≤0.001 ng/mL (p < 0.001). The patients with A-ADT for 1 year or longer had better BCFFS or OS than those for less than 1 year or those without A-ADT (p < 0.001). The best prognosis was demonstrated in patients treated with long-term A-ADT and nadir PSA ≤0.001 ng/mL in BCFFS (p < 0.001). CONCLUSION: The addition of long-term A-ADT over 1 year to RT demonstrated good treatment outcomes in patients with locally advanced prostate cancer. Achieving a nadir PSA value ≤0.001 ng/mL using combination therapy with RT and A-ADT is a powerful clinical predictor of treatment outcomes.

Evaluation of Prognostic Factors for the Parotid Cancer Treated With Surgery and Postoperative Radiotherapy.

OBJECTIVES: To investigate the prognostic factors and treatment outcomes of primary parotid carcinoma treated with surgery and postoperative radiotherapy (PORT). METHODS: We reviewed retrospectively 57 patients with primary parotid carcinoma who were treated with surgery and PORT between 2005 and 2014. Superficial parotidectomy was performed in 19 patients, total parotidectomy in 10 patients, and total parotidectomy with lymph node dissection in 28 patients PORT on the tumor bed was performed in 41 patients, while PORT on tumor bed and ipsilateral cervical lymph nodes was performed in 16 patients. RESULTS: With a median follow-up of 66 months, the 5-year overall survival, disease-free survival, locoregional control, and distant control rates were 77.0%, 60.2%, 77.6%, and 72.8%, respectively. The 5-year overall survival by stage was 100%, 100%, 80.0%, and 46.4% in stage I, II, III, and IV, respectively. Recurrences at primary lesions were found in seven patients, while at cervical nodes in six patients. Distant recurrences were developed in 12 patients. No patient with the low and intermediate histologic grade developed distant failure. As prognostic factors, the histologic grade for overall survival (P=0.005), pathological T-stage (P=0.009) and differentiation grade (P=0.009) for disease-free survival, pathological T-stage for locoregional control (P=0.007), and lympho-vascular invasion (P=0.023) for distant recurrence were significant on multivariate analysis. CONCLUSION: This study revealed that differentiation grade, histologic grade, pathological T-stage, and lympho-vascular invasion were significant independent prognostic factors on clinical outcomes.

Radiation hardness of cadmium telluride solar cells in proton therapy beam mode.

We evaluated the durability of cadmium telluride (CdTe) solar cells upon proton beam irradiation as well as the possibility of achieving a dosimeter usable in proton beam therapy by applying 100 MeV of pencil beam scanning (PBS) irradiation. Specifically, a 100 MeV proton PBS beam was applied at irradiation doses of 0, 1012, 1013, 1014, and 1015 cm-2. According to the results, the remaining factors (defined as the ratio of the degraded value to the initial value) of open-circuit voltage (Voc), short-circuit current (Jsc), fill-factor (FF), and efficiency (ƞ) which are solar cell performance parameters, were approximately 89%, 44%, 69%, and 30%, respectively, compared to those of the reference cell (without irradiation) at the highest dose of 1×1015 cm-2. In particular, the conversion efficiency, which is the main factor, was approximately 70% of that of the reference cell even at a high fluence of 1×1014 cm-2. In addition, we observed the projected range of the hydrogen atoms based on the PBS beam energy using the Tool for Particle Simulation software and assessed the amount of fluence accumulated in a CdTe cell. As the energy increased, the fluence accumulated inside the cell tended to decrease owing to the characteristics of the Bragg peak of the proton. Thus, the radiation damage to the cell induced by the proton beam was reduced. The results of this study are expected to provide valuable reference information for research on dosimetry sensors composed of thin-film solar cells, serving as the basis for future application in proton beam therapy with CdTe solar cells.

Prognostic significance of lymphovascular invasion in patients with prostate cancer treated with postoperative radiotherapy.

PURPOSE: To determine prognostic significance of lymphovascular invasion (LVI) in prostate cancer patients who underwent adjuvant or salvage postoperative radiotherapy (PORT) after radical prostatectomy (RP). MATERIALS AND METHODS: A total of 168 patients with prostate cancer received PORT after RP, with a follow-up of ≥12 months. Biochemical failure after PORT was defined as prostate-specific antigen (PSA) ≥0.2 ng/mL after PORT or initiation of androgen deprivation therapy (ADT) for increasing PSA levels regardless of the value. We analyzed the clinical outcomes including survivals, failure patterns, and prognostic factors affecting the outcomes. RESULTS: In total, 120 patients (71.4%) received salvage PORT after PSA levels were >0.2 ng/mL or owing to clinical failure. The 5-year biochemical failure-free survival (BCFFS), clinical failure-free survival (CFFS), distant metastasis-free survival (DMFS), overall survival, and cause-specific survival rates were 78.3%, 94.3%, 95.0%, 95.8%, and 97.3%, respectively, during a follow-up range of 12-157 months (median: 64 months) after PORT. On multivariate analysis, PSA level of ≤1.0 ng/mL at the time of receiving PORT predicted favorable BCFFS, CFFS, and DMFS. LVI predicted worse CFFS (p = 0.004) and DMFS (p = 0.015). Concurrent and/or adjuvant ADT resulted in favorable prognosis for BCFFS (p < 0.001) and CFFS (p = 0.017). CONCLUSION: For patients with adverse pathologic findings, PORT should be initiated as early as possible after continence recovery after RP. Even after administering PORT, LVI was an unfavorable predictive factor, and further intensive adjuvant therapy should be considered for these patients.

Intensity-modulated radiotherapy for stage I glottic cancer: a short-term outcomes compared with three-dimensional conformal radiotherapy.

PURPOSE: To investigate the differences in treatment outcomes between two radiation techniques, intensity-modulated radiotherapy (IMRT) and three-dimensional conformal radiotherapy (3DCRT). MATERIALS AND METHODS: We retrospectively analyzed 160 (IMRT = 23, 3DCRT = 137) patients with stage I glottic cancer treated from January 2005 through December 2016. The IMRT was performed with TomoTherapy (16 patients), volumetric-modulated arc therapy (6 patients), and step-and-shoot technique (1 patient), respectively. The 3DCRT was performed with bilateral parallel opposing fields. The median follow-up duration was 30 months (range, 31 to 42 months) in the IMRT group and 65 months (range, 20 to 143 months) in the 3DCRT group. RESULTS: The 5-year overall survival and 3-year local control rates of the 160 patients were 95.7% and 91.4%, respectively. There was no significant difference in 3-year local control rates between the IMRT and 3DCRT groups (94.4% vs. 91.0%; p = 0.587). Thirteen of 137 patients in the 3DCRT group had recurrences. In the IMRT group, one patient had a recurrence at the true vocal cord. Patients treated with IMRT had less grade 2 skin reaction than the 3DCRT group, but this had no statistical significance (4.3% vs. 21.2%; p = 0.080). CONCLUSION: IMRT had comparable outcomes with 3DCRT, and a trend of less acute skin reaction in stage I glottic cancer patients.