Woong-Ki Chung

Prognostic significance of interim 18F-FDG PET/CT after three or four cycles of R-CHOP chemotherapy in the treatment of diffuse large B-cell lymphoma

PURPOSE (18)F-fluoro-2-dexoy-D-glucose-positron emission tomography (FDG-PET)/computerised tomography (CT) has been used for staging and monitoring responses to treatment in patients with diffuse large B cell lymphoma (DLBCL). The sequential interim PET/CT was prospectively investigated to determine whether it provided additional prognostic information and could be a positive predictable value within patients with the same international prognostic index (IPI) after the use of rituximab in DLBCL. METHODS One hundred and sixty-one patients with newly diagnosed DLBCL were enroled; the assessment of the PET/CT was performed at the time of diagnosis and mid-treatment of rituxibmab, cyclophosphamide, doxorubicin, vincristine and prednisolone (R-CHOP). RESULTS Sixty-seven patients (41.6%) presented with advanced stage disease and 27 (16.8%) had bulky lesions. Forty-three patients (26.7%) continued to have positive metabolic uptakes with a significantly high relapse rate (62.8%) compared to the patients with a negative interim PET/CT (12.1%) (P<0.01). After a median follow-up of 30.8months, the positivity of interim PET/CT was found to be a prognostic factor for both overall survival (OS) and progression-free survival (PFS), with a hazard ratio of 4.07 (2.62-6.32) and 5.46 (3.49-8.52), respectively. In the low-risk IPI group, the 3-year OS and PFS rates were significantly different in the patients with positive (53.3% and 52.5%) and negative (93.8% and 88.3%) interim PET/CT, respectively (P<0.01). These significant prognostic differences of interim PET/CT responses were consistent with the results of the patients with high-risk IPI group (P<0.01). CONCLUSIONS Interim PET/CT scanning had a significant predictive value for disease progression and survival of DLBCL in post-rituximab treatment; it might be the single most important determinant of clinical outcome in patients with the same IPI risk.

Apoptosis and BCL-2 expression as predictors of survival in radiation-treated non–small-cell lung cancer

OBJECTIVES We assessed the role of apoptosis and the expression of bcl-2, p53, and c-myc oncoproteins in pretreatment histologic specimens as a predictor of response to radiation therapy and survival in non-small-cell lung cancer (NSCLC) patients. METHODS Pretreatment biopsy specimens of 68 patients with NSCLC (62 squamous cell carcinoma, 6 adenocarcinoma) were stained with hematoxylin and eosin. From 5 high-powered fields, the apoptotic index (AI) was calculated as the ratio of apoptotic tumor cells to the total number of tumor cells. Bcl-2, p53, and c-myc oncoprotein expression was detected by immunohistochemical staining. RESULTS Twenty-nine cases showed partial or complete remission, whereas 39 showed no response. AI ranged from 0.2 to 12.0% (mean +/- SD; 4.3 +/- 2.6%, median 4.0%). There was no difference in AI between responders (4.0 +/- 2.3) and nonresponders (4.5 +/- 2.8, p > 0.05). However, in the responders, AI was correlated with the degree of change in tumor volume (r = 0.41, p < 0.05). In an analysis of 53 subjects who survived more than 1 month after the completion of radiation therapy, the patients with a higher AI (n = 27, MST = 22.8 m) survived longer than those with a lower AI (n = 26, MST = 9.2, log-rank, p = 0.03). Patients expressing bcl-2 had poorer survival (n = 22, MST = 6.0 m) than patients without bcl-2 (n = 31, 22.8 m, p < 0.003). According to multivariate analysis, three variables, bcl-2 expression, AI, and response to radiation, were independent prognostic factors for survival. CONCLUSION A low level of spontaneous apoptosis and expression of apoptosis blocking bcl-2 protein in pretreatment histology predict a poor prognosis for radiation-treated NSCLC patients.

Effect of pentoxifylline on radiation response of non-small cell lung cancer: a phase III randomized multicenter trial.

PURPOSES The objectives of this prospective clinical trial were to determine whether pentoxifylline improves the radiation response and survival in patients with non-small cell lung cancer. MATERIALS AND METHODS From July 1993 through October 1994, 64 patients with histologically confirmed Stage I, II and III non-small cell lung cancer were randomly divided into pentoxifylline (Pento)+Radiotherapy (RT) group and RT alone group. Out of the 64 patients, only 47 patients who had measurable tumors on chest X-ray views were analyzed and divided into Pento+RT group (n=27) and RT alone group (n=20). Total tumor dose of 65-70 Gy was delivered as conventional fractionated radiation schedules. Pento was given to the patients 3 x 400 mg/day with a daily dose of 1200 mg during RT. RESULTS Complete response (CR), partial response (PR), and stable in Pento+RT group were three (11%), 13 (48%), and 11 (41%), respectively, as compared with corresponding values of three (15%), 13 (65%), and four (20%) in the RT alone group. The median time to relapse in the Pento+RT group was 11 months which was 2 months longer than for the RT alone group (P>0.05). All the patients in both groups showed lower than or equal to grade 2 dysphagia, odynophagia, pulmonary fibrosis, and pneumonitis. The median survival was 18 months in the Pento+RT group and 7 months in the RT alone group. The 1-year survival rate was 60% in the Pento+RT group and 35% in the RT alone group, the 2-year survival rate was 18% in the Pento+RT group and 12% in the RT alone group. But these differences were not statistically significant (P>0.05). CONCLUSION We concluded that Pento is a modestly effective radiation response modifier and provide benefit in the treatment of non-small cell lung cancer.

Metabolic Response of Lymph Nodes Immediately After RT Is Related With Survival Outcome of Patients With Pelvic Node-Positive Cervical Cancer Using Consecutive [18F]fluorodeoxyglucose-Positron Emission Tomography/Computed Tomography

PURPOSE To evaluate the metabolic response of uterine cervix and pelvic lymph nodes (LNs) using consecutive 18F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) immediately after RT and to correlate survival outcome with the metabolic response. METHODS AND MATERIALS We retrospectively reviewed 48 patients with cervical cancer who had positive pelvic LNs by preradiation therapy (pre-RT) PET/CT. All patients underwent PET/CT scans immediately after RT (inter-RT PET/CT) after median 63 Gy to the gross LNs. The metabolic response of the LNs was assessed quantitatively and semiquantitatively by measurement of the maximal standardized uptake value (SUVmax). RESULTS Classifying the metabolic response of all nodal lesions, 37 patients (77%) had LNs with complete metabolic response on the inter-RT PET/CT (LNCMRi), and 11 patients had a non-LNCMRi, including 4 patients with progressive metabolic disease. The overall 3-year survival rates were 83% for the patients with LNCMRi and 73% for the non-LNCMRi group (P=.038). The disease-free survival for patients with LNCMRi were significantly better than that for the non-LNCMRi group (71% vs 18%, respectively, P<.001). The 3-year distant metastasis-free survival rates were 79% for the patients with LNCMRi and 27% for the non-LNCMRi group (P<.001). There were no statistically significant differences in overall survival (76% vs 86%, respectively, P=.954) and disease-free survival rates (58% vs 61%, respectively, P=.818) between the CMR of primary cervical tumor and the non-CMR groups. CONCLUSIONS The results showed a significant correlation between survival outcome and the interim metabolic response of pelvic LNs. CMR of nodal lesion on inter-RT PET/CT had excellent overall survival, disease-free survival and distant metastasis-free survival rates. This suggested that PET/CT immediately after RT can be a useful tool for the evaluation of the interim response of the LNs and identify a subset of patients with a high risk of recurrence and poor survival in patients with cervical cancer with initial positive LNs.

The Efficacy of an Induction Chemotherapy Combination with Docetaxel, Cisplatin, and 5-FU Followed by Concurrent Chemoradiotherapy in Advanced Head and Neck Cancer

PURPOSE This study was performed to determine the feasibility and safety of the use of induction chemotherapy combined with docetaxel, cisplatin, and 5-fluorouracil (TPF) followed by concurrent chemoradiation therapy for locally advanced squamous cell carcinoma of the head and neck (SCCHN). MATERIALS AND METHODS The patients, that were initially not treated for locally advanced SCCHN, underwent three cycles of induction chemotherapy every 3 weeks at a dose of 70 mg/m(2) docetaxel D1, 75 mg/m(2) cisplatin D1, 1000 mg/m(2) 5-FU D1-4, and subsequently received concurrent chemoradiation therapy. RESULTS Forty-nine patients were enrolled in this study and forty-three of the patients completed the treatment. The median duration of follow-up was 18 months (range, 6 approximately 39 months). All of the patients had stage III (26.5%) or IV (73.5%) squamous cell carcinoma. After sequential therapy, a complete response and partial response was seen in 28 (65.2%) and 13 (30.2%) patients, respectively. The overall response rate was 95.4%. Overall survival and progression-free survival (PFS) at 2 years were 88.7% and 69.7%, respectively. Grade 3 approximately 4 neutropenia occurred in 42.2% of the patients and grade 4 thrombocytopenia in 1 cycle (0.7%). Two patients (4.1%) died during the induction chemotherapy due to pneumonia and a subdural hemorrhage, respectively. The group of patients over 65 years of age showed a significant lower dose intensity than that of patients under 65 years of age, but PFS was not significantly different between two groups (p=0.105). CONCLUSION TPF induction chemotherapy followed by concurrent chemoradiotherapy showed a high level of CR and moderate treatment-induced toxicity. Adequate dose modification in elderly patients should be considered to maintain efficacy and avoid treatment-related toxicity.

The metabolic response using 18F-fluorodeoxyglucose-positron emission tomography/computed tomography and the change in the carcinoembryonic antigen level for predicting response to pre-operative chemoradiotherapy in patients with rectal cancer.

BACKGROUND AND PURPOSE To predict tumor regression in pre-operative chemoradiotherapy (CRT) using (18)F-fluorodeoxyglucose-positron emission tomography/computed tomography (PET/CT) and serum carcinoembryonic antigen (CEA) in patients with rectal cancer. MATERIALS AND METHODS The metabolic response of the tumor was assessed by determining the maximal standardized uptake value (SUV(max)), absolute difference (ΔSUV(max)), and SUV reduction ratio (SRR) on pre- and post-CRT PET/CT scans. The serum CEA, absolute difference (ΔCEA), and the CEA reduction ratio (CRR) were also determined. A receiver-operating characteristic (ROC) curve was generated. RESULTS Of all seventy two patients, mean pre- and post-CRT SUV(max) was 14.9 and 5.8, respectively. The mean pre- and post-CRT CEA level was 15.5 ng/ml and 5.4 ng/ml, respectively. Forty-three patients (59.8%) were classified as responders (Dworaks tumor regression grade 3-4) and 36 patients (50%) achieved tumor down-staging. ROC analysis showed that both post-CRT SUV(max) and SRR were predictive factors for responders (p=0.03 and p=0.02, respectively). A threshold of post-CRT SUV(max) was 5.4 and that of SRR was 53.1%. Pre-CRT SUV(max), ΔSUV(max), and all parameters in regard to CEA were not significant in ROC analysis. CONCLUSIONS The post-CRT SUV(max) and SRR are potential factors for predicting tumor response in pre-operative CRT. The patients with lower post-CRT SUV(max) and higher SRR could be expected to achieve maximum tumor regression after pre-operative CRT in this study.

The prognostic significance of surgically treated hydrocephalus in leptomeningeal metastases.

OBJECTIVE The median survival of leptomeningeal metastases is short despite therapy and is sometime associated with hydrocephalus. We investigated the prognostic significance of surgically treated hydrocephalus in leptomeningeal metastases. MATERIALS AND METHODS Between December 2005 and November 2012, 1343 patients had brain metastases from systemic solid tumors. Of these, 71 patients (5.3%) experienced leptomeningeal metastases from 45 lung cancers, 14 breast cancers, 4 gastric cancers and 8 other cancers. The mean age was 60 years (range 37-89). The clinical symptoms presented in the cerebral hemisphere and cerebellum in 58 patients, cranial nerve in 7 patients and spinal cord and nerves in 6 patients. Twenty-nine (40.8%) patients were Radiation Therapy Oncology Group recursive partitioning analysis (RTOG-RPA) class II and 42 (59.2%) were class III. Hydrocephalus was associated in 18 (25.4%) patients and 7 patients underwent ventriculoperioneal shunt. The primary cancer, clinical symptoms, RTOG-RPA class, surgically treated hydrocephalus and systemic chemotherapy were analyzed as the prognostic factors for overall survival. RESULTS The overall incidence of leptomeningeal seeding was 5.0% of the brain metastases. The median duration of leptomeningeal metastases from first brain metastasis was 4.0 months and 24 (33.8%) patients showed leptomeningeal metastases as the first form of brain metastasis. The median overall survival (OS) was 2.1 months. Based on the univariate and multivariate analyses, RTOG-RPA class II patients, treatment of leptomeningeal metastases (such as radiotherapy or intrathecal chemotherapy) and systemic chemotherapy improved OS with statistical significance. Surgically untreated hydrocephalus (median OS, 1.7 months) showed poor OS compared with surgically treated hydrocephalus (median OS, 5.7 months) and no hydrocephalus (median OS, 2.3 months) without statistical significance. CONCLUSIONS The leptomeningeal metastases were often associated with hydrocephalus and the surgical treatment was helpful in limited patients. The prognosis was related with RTOG-RPA class and treatment of local and systemic treatment.

VEGF as a Predictor for Response to Definitive Chemoradiotherapy and COX-2 as a Prognosticator for Survival in Esophageal Squamous Cell Carcinoma

We investigated the patterns of pretreatment expression of the epidermal growth factor receptor (EGFR), vascular endothelial growth factor (VEGF), and cyclooxygenase-2 (COX-2) by immunohistochemical staining and determined their correlation with treatment response and survival in 44 patients with esophageal squamous cell carcinoma (ESCC) treated with definitive concurrent chemoradiotherapy (CCRT). The definitive CCRT consisted of a median dose of 54 Gy (range: 40.0-68.4 Gy) and two cycles of concurrent administration of mostly 5-fluorouracil + cisplatinum. High expression of EGFR, VEGF, and COX-2 was found in 79.5%, 31.8%, and 38.6%, respectively. The Cox regression analysis for overall survival (OS) showed that both the treatment response and COX-2 expression were significant. The 3-yr OS rates of patients that achieved a complete response and those that did not were 46.7% and 5.3%, respectively (P = 0.006). The logistic regression analysis for treatment response with various parameters showed that only a high expression of VEGF was significantly associated with a complete response. Unlike other well-known studies, higher expression of VEGF was significantly correlated with a complete response to CCRT in this study. However, higher expression of COX-2 was significantly associated with shorter survival. These results suggest that VEGF might be a predictive factor for treatment response and COX-2 a prognostic factor for OS in patients with ESCC after definitive CCRT.

RESPIRATORY MOTIONAL EFFECT ON CONE-BEAM CT IN LUNG RADIATION SURGERY

The cone-beam CT (CBCT), which is acquired using an on-board imager (OBI) attached to a linear accelerator, is used effectively in the verification of setup accuracy for lung radiation surgery. In this study, the respiratory organ motional effect on the CBCT was evaluated with a properly devised phantom system, and the level of possible error in conditions of a real clinical process was assessed. In a comparison study between the CBCT in static status and CBCT images acquired in 20 different motional cases, we confirmed that the image quality and information of CBCT were degraded, with an increase of motional ranges in the region of inhomogeneous structures. The 4D-CT MIP (50 approximately 55%) for the planning of lung radiation surgery and the 4D-CT MIP (full phase) were compared with CBCT in the various motional cases for the evaluation of the influence of the motional effect on CBCT in the process of the setup error correction. The average ratio of relative difference between plan CT: 4D-CT MIP (50% approximately 55%) and CBCT was 5.79% and between plan CT: 4D-CT MIP (50% approximately 55%) and 4D-CT MIP (full phase) was 42.95% in the phantom study. In the analysis of clinical cases of lung radiation surgery, the gross tumor volumes were compared in each CT image. The average ratio of relative difference between plan CT: 4D-CT MIP (50 approximately 55%) and CBCT was 10.72% and between plan CT: 4D-CT MIP (50 approximately 55%) and 4D-CT MIP (full phase) was 28.19%. These results showed that, although a respiratory organ motional effect on CBCT introduced variation in image quality, the error as a result of this variation could be estimated relatively low in the setup error correction for a gated-lung radiation surgery when the planning was performed in 4D-CT MIP (50 approximately 55%), which already included a related signal of motional effect.

The Role of Radiotherapy in the Treatment of Gastric Mucosa-Associated Lymphoid Tissue Lymphoma

Purpose To assess radiotherapy for patients with early stage gastric mucosa-associated lymphoid tissue (MALT) lymphoma with respect to survival, treatment response, and complications. Materials and Methods Enrolled into this study were 48 patients diagnosed with gastric MALT lymphoma from January 2000 to September 2012. Forty-one patients had low grade and seven had mixed component with high grade. Helicobacter pylori eradication was performed in 33 patients. Thirty-four patients received radiotherapy alone. Ten patients received chemotherapy before radiotherapy, and three patients underwent surgery followed by chemotherapy and radiotherapy. One patient received surgery followed by radiotherapy. All patients received radiotherapy of median dose of 30.6 Gy. Results The duration of follow-up ranged from 6 to 158 months (median, 48 months). Five-year overall survival and cause-specific survival rates were 90.3% and 100%. All patients treated with radiotherapy alone achieved pathologic complete remission (pCR) in 31 of the low-grade and in three of the mixed-grade patients. All patients treated with chemotherapy and/or surgery prior to radiotherapy achieved pCR except one patient who received chemotherapy before radiotherapy. During the follow-up period, three patients developed diffuse large B-cell lymphoma in the stomach, and one developed gastric adenocarcinoma after radiotherapy. No grade 3 or higher acute or late complications developed. One patient, who initially exhibited gastroptosis, developed mild atrophy of left kidney. Conclusion These findings indicate that a modest dose of radiotherapy alone can achieve a high cure rate for low-grade and even mixed-grade gastric MALT lymphoma without serious toxicity. Patients should be carefully observed after radiotherapy to screen for secondary malignancies.