Hong Ryull Pyo

Synchronous Coexpression of Epidermal Growth Factor Receptor and Cyclooxygenase-2 in Carcinomas of the Uterine Cervix A Potential Predictor of Poor Survival

Purpose: To evaluate the potential of the new prognostic information gained by analyzing the coexpression of epidermal growth factor receptor (EGFR) and cyclooxygenase-2 (COX-2) in cervical cancer patients. Experimental Design: Sixty-eight patients with International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix, who underwent concurrent chemoradiotherapy between 1993 and 1996, were divided into the following four groups according to their immunoreactivities for EGFR and COX-2 in paraffin-embedded sections: (a) the EGFR-negative/COX-2-negative group (n = 11); (b) the EGFR-negative/COX-2-positive group (n = 8); (c) the EGFR-positive/COX-2-negative group (n = 27); and (d) the EGFR-positive/COX-2-positive group (n = 22). The clinical features, patterns of treatment failure, and survival data in the four groups were compared. Results: Positive immunoreactivity for EGFR and COX-2 was observed in 49 of 68 (72%) and 19 of 68 (28%), respectively. However, no strong correlation was found between the levels of EGFR and COX-2 immunopositivity (R2 = 0.05, P = 0.07). Patients in the EGFR-positive/COX-2-positive group had a higher likelihood of locoregional recurrence than those in the other three groups (P = 0.02). Of the patients in the four groups, patients positive for both oncoproteins were found to have the worst prognosis with an overall 5-year disease-free survival rate of 55% compared with 91% for the EGFR-negative/COX-2-negative patients, 88% for the EGFR-negative/COX-2-positive patients, and 69% for the EGFR-positive/COX-2-negative patients (P = 0.05, log-rank test). In addition, the synchronous coexpression of the EGFR and COX-2 oncoproteins was found to be an independent prognostic factor by univariate and multivariate analyses (relative risk = 4.0, P = 0.03). Conclusions: Given these observations, we conclude that the coexpression of EGFR and COX-2 immunoreactivity may be used as a potent molecular risk factor for predicting the poor survival of patients with the International Federation of Gynecology and Obstetrics stage IIB squamous cell carcinoma of the uterine cervix.

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 0.80 to 3.15. Our results showed that the S‐index provides a more reliable and accurate measure of dose homogeneity than that given by conventional methods. A guideline for evaluating the dose homogeneity of treatment plans based on the S‐index and its relation to equivalent uniform dose is discussed. PACS numbers: 87.53.Xd, 87.53.Tf

Combined chemotherapy and radiation versus radiation alone in the management of localized angiocentric lymphoma of the head and neck

BACKGROUND AND PURPOSE To clarify the clinical benefit derived from the combined modality therapy (CMT) comprised of chemotherapy and involved-field radiotherapy (XRT) for stage I and II angiocentric lymphomas of the head and neck. MATERIAL AND METHODS Of 143 patients with angiocentric lymphoma of the head and neck treated at the Yonsei Cancer Center between 1976 and 1995, 104 patients (XRT group) received involved-field XRT alone with a median dose of 50.4 Gy (range: 20-70 Gy), while 39 patients (CMT group) received a median three cycles (range: 1-6 cycles) of chemotherapy before starting involved-field XRT. The response rate, patterns of failure, complications, and survival data of the XRT group were compared with those of the CMT group. RESULTS Despite a higher response rate, local failure was the most common pattern of failure in patients of the both groups. The patterns of failure, including the systemic relapse rate were not influenced by the addition of combination chemotherapy. Although both modalities were well tolerated by the majority of patients, aberrant immunologic disorders or medical illnesses, such as a hemophagocytic syndrome, sepsis, intractable hemorrhage, or the evolution of second primary malignancies were more frequently observed in patients of the CMT group. The prognosis of patients in the XRT group was relatively poor, with a 5-year overall actuarial survival rate of 38% and disease-free survival rate of 32%, respectively. However, their clinical outcome was not altered by the addition of systemic chemotherapy. Achieving complete remission was the most important prognostic factor on univariate and multivariate analyses, but treatment modality was not found to be a prognostic variable influencing survival. CONCLUSIONS Involved-field XRT alone for angiocentric lymphoma of the head and neck was insufficient to achieve an improved survival rate, but the combination of chemotherapy and involved-field XRT failed to demonstrate any therapeutic advantage over involved-field XRT alone.

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.

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.

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 2.0 Gy was delivered to the planning target volume with a SIB of 0.4 Gy to the gross tumor volume with a total dose of 60 Gy to the gross tumor volume and 50 Gy to the planning target volume in 25 fractions during 5 weeks. Twenty patients received temozolomide chemotherapy. RESULTS At a median follow-up of 13.4 months (range, 3.7-55.9 months), median survival was 14.8 months. One- and 2-year survival rates were 78% and 65%, respectively, for patients with grade III tumors and 56% and 31%, respectively, for patients with grade IV tumors. Age (≤50 vs. >50), grade (III vs. IV), subtype (astrocytoma vs. oligodendroglioma or mixed), and a Zubrod performance score (0-1 vs. >2) were predictive of survival. Of 25 (63%) patients who had recurrences, 17 patients had local failure, 9 patients had regional failure, and 1 patient had distant metastasis. Toxicities were acceptable. CONCLUSIONS SIB-IMRT with the dose/fractionation used in this study is feasible and safe, with a survival outcome similar to the historical control. The shortening of treatment time by using SIB-IMRT may be of value, although further investigation is warranted to prove its survival advantage.

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. Eighteen patients had Stage IIIA and 31 had Stage IIIB. By using 3D conformal radiotherapy (RT) techniques, a dose of 1.8 Gy was delivered to the planning target volume with a synchronous boost of 0.6 Gy to the GTV, with a total dose of 60 Gy to the GTV and 45 Gy to the planning target volume in 25 fractions during 5 weeks. All patients received weekly chemotherapy consisting of paclitaxel and carboplatin during RT. RESULTS With a median follow-up of 36.8 months (range, 29.0-45.5 months) for surviving patients, median survival was 28.1 months. One-, 2- and 3-year overall survival rates were 77%, 56.4%, and 43.8%, respectively. Corresponding local progression-free survival rates were 71.2%, 53.7%, and 53.7%. Compliance was 90% for RT and 88% for chemotherapy. Acute esophagitis of Grade 2 or higher occurred in 29 patients. Two patients with T4 lesions died of massive bleeding and hemoptysis during treatment (Grade 5). Overall late toxicity was acceptable. CONCLUSIONS Based on the favorable outcome with acceptable toxicity, the acceleration scheme using 3D conformal GTV boost in this trial is warranted to compare with conventional fractionation in a Phase III trial.

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. RESULTS For both intra- and interfractional movements, the average coverage index and conformity index of the target were reduced in all directions. For interfractional movements, the magnitude of dose reduction was greater in the LR direction than in the AP, PA, SI. and IS directions. Although the reduction of target dose was proportional to the magnitude of intrafractional movement in all directions, a proportionality between dose reduction and the magnitude of interfractional target movement was clear only in the LR direction. Like the coverage index and conformity index, the equivalent uniform dose and homogeneity index showed similar reductions for both types of target movements. CONCLUSIONS Small target movements can significantly reduce target proton radiotherapy dose during treatment of prostate cancer patients. Attention should be given to interfractional target movement along the longitudinal direction, as image-guided radiotherapy may be ineffective if margins are not sufficient.

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

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.

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

PurposeGastrointestinal stromal tumors (GISTs) rarely originate in the rectum. We investigated the clinicopathologic characteristics of rectal GISTs.MethodsWe analyzed the medical records of seven patients who underwent surgery for GIST of the rectum between 1998 and 2003.ResultsThere were two men and five women with a median age of 55 years (range, 41–72 years) at the time of diagnosis. The median follow-up period was 23 months (range, 7–75 months). The chief symptoms were hematochezia, constipation, and anal pain. All patients underwent curative resection; in the form of abdominoperineal resection in five patients, transanal excision in one, and Hartmanns operation with prostatectomy in one. The median tumor size was 6.6 cm (range, 1–12 cm). Four patients received adjuvant radiation therapy. Local recurrence developed in two patients; 54 months and 23 months after surgery, respectively.ConclusionThe common symptoms of rectal GIST were the same as those of other rectal tumors. Curative surgical resection should be done, but further studies are necessary to investigate better adjuvant treatment strategies for patients with rectal GISTs

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. Results The multi-purpose nozzle can deliver both wobbling proton beam and active scanning proton beam, and a multi-leaf collimator has been installed in the downstream of the nozzle. The dedicated scanning nozzle can deliver active scanning proton beam with a helium gas filled pipe minimizing unnecessary interactions with the air in the beam path. The equipment was provided by Sumitomo Heavy Industries Ltd., RayStation from RaySearch Laboratories AB is the selected treatment planning system, and data management will be handled by the MOSAIQ system from Elekta AB. Conclusion The SMC-PTS located in Seoul, Korea, is scheduled to begin treating cancer patients in 2015.