Predictive Value of F-FDG PET/CT Using Machine Learning for Pathological Response to Neoadjuvant Concurrent Chemoradiotherapy in Patients with Stage III Non-Small Cell Lung Cancer.

We investigated predictions from 18F-FDG PET/CT using machine learning (ML) to assess the neoadjuvant CCRT response of patients with stage III non-small cell lung cancer (NSCLC) and compared them with predictions from conventional PET parameters and from physicians. A retrospective study was conducted of 430 patients. They underwent 18F-FDG PET/CT before initial treatment and after neoadjuvant CCRT followed by curative surgery.

Investigations of line scanning proton therapy with dynamic multi-leaf collimator.

Purpose: Scanning proton therapy has dosimetric advantage over passive treatment, but has a large penumbra in low-energy region. This study investigates the penumbra reduction when multi-leaf collimators (MLCs) are used for line scanning proton beams and secondary neutron production from MLCs.

Methods: Scanning beam plans with and without MLC shaping were devised.

Ablative dose proton beam therapy for stage I and recurrent non-small cell lung carcinomas : Ablative dose PBT for NSCLC.

Purpose: To evaluate the efficacy and safety of ablative dose hypofractionated proton beam therapy (PBT) for patients with stage I and recurrent non-small cell lung carcinoma (NSCLC).

Patients And Methods: A total of 55 patients with stage I (n = 42) and recurrent (n = 13) NSCLC underwent hypofractionated PBT and were retrospectively reviewed. A total dose of 50-72 CGE (cobalt gray equivalent) in 5-12 fractions was delivered.

The first private-hospital based proton therapy center in Korea; status of the Proton Therapy Center at Samsung Medical Center.

Purpose: The purpose of this report is to describe the proton therapy system at Samsung Medical Center (SMC-PTS) including the proton beam generator, irradiation system, patient positioning system, patient position verification system, respiratory gating system, and operating and safety control system, and review the current status of the SMC-PTS.

Materials And Methods: The SMC-PTS has a cyclotron (230 MeV) and two treatment rooms: one treatment room is equipped with a multi-purpose nozzle and the other treatment room is equipped with a dedicated pencil beam scanning nozzle. The proton beam generator including the cyclotron and the energy selection system can lower the energy of protons down to 70 MeV from the maximum 230 MeV.

Radical prostatectomy versus external beam radiotherapy for localized prostate cancer: Comparison of treatment outcomes.

Purpose: We retrospectively compared the treatment outcomes of localized prostate cancer between radical prostatectomy (RP) and external beam radiotherapy (EBRT).

Materials And Methods: We retrospectively analyzed 738 patients with localized prostate cancer who underwent either RP (n = 549) or EBRT (n = 189) with curative intent at our institution between March 2001 and December 2011. Biochemical failure was defined as a prostate-specific antigen (PSA)  level of ≥ 0.

Suggestion for the prostatic fossa clinical target volume in adjuvant or salvage radiotherapy after a radical prostatectomy.

Background And Purpose: To assess the location of recurrent tumors and suggest the optimal target volume in adjuvant or salvage radiotherapy (RT) after a radical prostatectomy (RP).

Material And Methods: From January 2000 to December 2012, 113 patients had been diagnosed with suspected recurrent prostate cancer by MRI scan and received salvage RT in the Samsung Medical Center. This study assessed the location of the suspected tumor recurrences and used the inferior border of the pubic symphysis as a point of reference.

A phase II study of hypofractionated proton therapy for prostate cancer.

Background: Hypofractionated radiotherapy potentially offers therapeutic gain for prostate cancer. We investigated the feasibility of hypofractionated proton therapy (PT).

Material And Methods: Eighty-two patients with biopsy-proven T1-3N0M0 prostate adenocarcinoma and no history of androgen deprivation therapy were randomly assigned to five different dose schedules: Arm 1, 60 CGE (cobalt gray equivalent = proton dose in Gy × 1.

High dose involved field radiation therapy as salvage for loco-regional recurrence of non-small cell lung cancer.

Purpose: To determine the effectiveness of salvage radiation therapy (RT) in patients with loco-regional recurrences (LRR) following initial complete resection of non-small cell lung cancer (NSCLC) and assess prognostic factors affecting survivals.

Materials And Methods: Between 1994 and 2007, 64 patients with LRR after surgery of NSCLC were treated with high dose RT alone (78.1%) or concurrent chemo-radiation therapy (CCRT, 21.

The expression of DNA damage checkpoint proteins and prognostic implication in metastatic brain tumors.

The most important therapeutic tool in brain metastasis is radiation therapy. However, resistance to radiation is a possible cause of recurrence or treatment failure. Recently, DNA damage checkpoint signaling pathway activation after irradiation has received increasing attention.

Simultaneous integrated boost intensity-modulated radiotherapy in patients with high-grade gliomas.

Purpose: We analyzed outcomes of simultaneous integrated boost (SIB) intensity-modulated radiotherapy (IMRT) in patients with high-grade gliomas, compared with a literature review.

Methods And Materials: Forty consecutive patients (WHO grade III, 14 patients; grade IV, 26 patients) treated with SIB-IMRT were analyzed. A dose of 2.

Phase II trial of concurrent radiation and weekly cisplatin followed by VIPD chemotherapy in newly diagnosed, stage IE to IIE, nasal, extranodal NK/T-Cell Lymphoma: Consortium for Improving Survival of Lymphoma study.

Purpose: On the basis of the benefits of frontline radiation in early-stage, extranodal, natural killer (NK)/T-cell lymphoma (ENKTL), we conducted a phase II trial of concurrent chemoradiotherapy (CCRT) followed by three cycles of etoposide, ifosfamide, cisplatin, and dexamethasone (VIPD).

Patients And Methods: Thirty patients with newly diagnosed, stages IE to IIE, nasal ENKTL received CCRT (ie radiation 40 to 52.8 Gy and cisplatin 30 mg/m(2) weekly).

A Phase II study of synchronous three-dimensional conformal boost to the gross tumor volume for patients with unresectable Stage III non-small-cell lung cancer: results of Korean Radiation Oncology Group 0301 study.

Purpose: We evaluated the efficacy of synchronous three-dimensional (3D) conformal boost to the gross tumor volume (GTV) in concurrent chemoradiotherapy for patients with locally advanced non-small-cell lung cancer (NSCLC).

Methods And Materials: Eligibility included unresectable Stage III NSCLC with no pleural effusion, no supraclavicular nodal metastases, and Eastern Cooperative Oncology Group performance score of 0-1. Forty-nine patients with pathologically proven NSCLC were enrolled.

Cyclooxygenase-2 expression in pretreatment biopsy as a predictor of tumor responses after preoperative chemoradiation in rectal cancer.

Objective: To determine whether cyclooxygenase-2 (COX-2) expression in pretreatment biopsy specimens is a useful predictive marker of tumor response to preoperative chemoradiation (CRT) in rectal cancer.

Design: Case series.

Setting: Colorectal cancer clinic.

Randomized phase 2 study of subcutaneous amifostine versus epoetin-alpha given 3 times weekly during concurrent chemotherapy and hyperfractionated radiotherapy for limited-disease small cell lung cancer.

Background: The purpose of the current study was to investigate the role of amifostine and epoetin-alpha in reducing severe toxicities during concurrent chemo-hyperfractionated radiotherapy (CCRT) for limited disease small cell lung cancer (LD-SCLC).

Methods: Seventy-six patients with LD-SCLC were enrolled. The treatment schedule was consisted of two 28-day cycles of cisplatin at a dose of 30 mg/m2 (Days 1 and 8) and irinotecan at a dose of 60 mg/m2 (Days 1, 8, and 15) followed by two 21-day cycles of cisplatin at a dose of 60 mg/m2 (Day 1) and etoposide at a dose of 100 mg/m2 (Days 1-3) with concurrent twice-daily thoracic radiotherapy for a total of 45 grays.

Primary chemotherapy for newly diagnosed nonsmall cell lung cancer patients with synchronous brain metastases compared with whole-brain radiotherapy administered first : result of a randomized pilot study.

Background: This randomized pilot trial investigated whether primary chemotherapy was feasible in terms of efficacy, survival, toxicity profile, and quality of life compared with whole-brain radiotherapy (WBRT) given first in chemotherapy-naive patients nonsmall cell lung cancer (NSCLC) with synchronous brain metastasis when neurologic symptoms or signs are absent or controlled by supportive care.

Methods: After stratification by Eastern Cooperative Oncology Group performance status (ECOG PS) (0-1 vs 2), the number of intracranial metastases (<3 vs 3< or =), and the presence of extrathoracic extracranial metastasis, eligible patients were randomized to the primary chemotherapy arm or the WBRT-first arm. World Health Organization (WHO) response criteria, National Cancer Institute Common Toxicity Criteria (NCI-CTC; version 2.

Inter- and intrafractional movement-induced dose reduction of prostate target volume in proton beam treatment.

Purpose: To quantify proton radiotherapy dose reduction in the prostate target volume because of the three-dimensional movement of the prostate based on an analysis of dose-volume histograms (DVHs).

Methods And Materials: Twelve prostate cancer patients underwent scanning in supine position, and a target contour was delineated for each using a proton treatment planning system. To simulate target movement, the contour was displaced from 3 to 15 mm in 3-mm intervals in the superior-to-inferior (SI), inferior-to-superior (IS), anterior-to-posterior (AP), posterior-to-anterior (PA), and left-to-right (LR) directions.

SMART (simultaneous modulated accelerated radiotherapy) for locally advanced nasopharyngeal carcinomas.

Background: Concurrent chemoradiotherapy is commonly used for locally advanced nasopharyngeal carcinoma (NPC). We retrospectively analyzed the clinical outcomes of simultaneous modulated accelerated radiotherapy (SMART) with concurrent chemotherapy.

Methods: Between January 2003 and May 2005, 24 patients with stage IIB to IVB NPC underwent SMART encompassing 3 targets: gross tumor volume (GTV), high-risk subclinical disease (CTV1), and low-risk subclinical disease (CTV2).

Effect of radiation scattering on dose uniformity in open and closed cell culture vessels.

Purpose: Dose uniformity in cell culture vessels such as Petri dishes and anoxic irradiation chambers is very important in radiobiological work as dose uniformity affects cell survival probabilities. In this study, we investigated X-ray dose inhomogeneity, caused by scattering, in typical culture vessels.

Materials And Methods: Three different cubic cell culture vessels, with side lengths of 10 cm, 15 cm and 20 cm, were designed and irradiated by X-rays of 6 MV and 15 MV at a source-to-surface distance (SSD) of 100 cm using a Varian 2,100CD linear accelerator.

A new homogeneity index based on statistical analysis of the dose-volume histogram.

The goal of the present study was to develop a new dose-volume histogram (DVH)- based homogeneity index for effectively evaluating the dose homogeneity of intensity-modulated radiotherapy plans. The new index, called the sigma-index ("S-index") is defined as the standard deviation of the normalized differential DVH curve. In a study of 16 patients with brain tumors at our institution, the S-index was found to vary from 0.

Gastrointestinal stromal tumor of the rectum: an analysis of seven cases.

Purpose: Gastrointestinal stromal tumors (GISTs) rarely originate in the rectum. We investigated the clinicopathologic characteristics of rectal GISTs.

Methods: We analyzed the medical records of seven patients who underwent surgery for GIST of the rectum between 1998 and 2003.

A comparative study of volumetric analysis, histopathologic downstaging, and tumor regression grade in evaluating tumor response in locally advanced rectal cancer following preoperative chemoradiation.

Purpose: To compare tumor volume reduction rate, histopathologic downstaging, and tumor regression grade (TRG) among tumor responses in rectal cancer after preoperative chemoradiotherapy (CRT).

Patients And Methods: Between 2002 and 2004, 30 patients with locally advanced rectal cancer underwent preoperative CRT, followed by surgical resection. Magnetic resonance volumetry was performed before and after CRT.

Evaluation of parotid gland function following intensity modulated radiation therapy for head and neck cancer.

Purpose: This study was undertaken to determine the parotid gland tolerance dose levels following intensity modulated radiation therapy (IMRT) for treating patients who suffered with head and neck cancer.

Materials And Methods: From February 2003 through June 2004, 34 head and neck patients with 6 months of follow-up were evaluated for xerostomia after being treated by IMRT. Their median age was 59 years (range: 29~78).

CT-guided intracavitary radiotherapy for cervical cancer: Comparison of conventional point A plan with clinical target volume-based three-dimensional plan using dose-volume parameters.

Purpose: To perform an intracavitary radiotherapy (ICR) plan comparison between the conventional point A plan (conventional plan) and computed tomography (CT)-guided clinical target volume-based plan (CTV plan) by analysis of the quantitative dose-volume parameters and irradiated volumes of organs at risk in patients with cervical cancer.

Methods And Materials: Thirty plans for 192Ir high-dose-rate ICR after 30-40-Gy external beam radiotherapy were investigated. CT images were acquired at the first ICR session with artifact-free applicators in place.

Phase II study of induction chemotherapy with gemcitabine and vinorelbine followed by concurrent chemoradiotherapy with oral etoposide and cisplatin in patients with inoperable stage III non-small-cell lung cancer.

Purpose: For locoregionally advanced inoperable non-small-cell lung cancer (NSCLC), concurrent chemoradiotherapy has become a standard therapy. We conducted a Phase II trial to examine the efficacy and toxicity of adding gemcitabine and vinorelbine induction chemotherapy to concurrent chemoradiotherapy with oral etoposide and cisplatin.

Methods And Materials: Eligibility included inoperable clinical Stage III NSCLC without pleural effusion, ECOG performance status 0-1, and weight loss < or =5%.

Dose-volumetric parameters of acute esophageal toxicity in patients with lung cancer treated with three-dimensional conformal radiotherapy.

Purpose: To retrospectively evaluate which dose-volumetric parameters are associated with the risk of > or = Grade 3 acute esophageal toxicity (AET) in lung cancer patients treated with three-dimensional conformal radiotherapy (3D-CRT).

Methods And Materials: One hundred twenty-four lung cancer patients treated curatively with 3D-CRT were retrospectively analyzed. All patients received conventionally fractionated radiotherapy (RT) with median dose of 60 Gy (range, 54-66 Gy) delivered in 30 fractions (range, 27-33 fractions).