Kazushige Atsumi

CT and MRI findings of human herpesvirus 6-associated encephalopathy: comparison with findings of herpes simplex virus encephalitis.

OBJECTIVE It is important to differentiate human herpesvirus 6 (HHV-6)-associated encephalopathy from herpes simplex encephalitis (HSE). Although these conditions are similar with regard to involvement of the mesial temporal lobe, HSE is sensitive to acyclovir but HHV-6 encephalopathy is not. We compared the imaging findings of the two conditions. MATERIALS AND METHODS We encountered eight cases of HHV-6 encephalopathy and nine cases of HSE. We divided an observation time into early, middle, and late periods defined as 0-2, 3-30, and more than 30 days from the onset of neurologic symptoms. Differences between HHV-6 encephalopathy and HSE on CT scans in the early period and in distribution and temporal changes in the affected regions on MR images in the three periods were analyzed. RESULTS At MRI in the early and middle periods, all eight patients with HHV-6 encephalopathy had exclusive involvement of the mesial temporal lobes, and all nine patients with HSE had involvement of both the mesial temporal lobes and the extratemporal regions (p < 0.01). Among patients who underwent head MRI, six of six with HHV-6 encephalopathy but none of six with HSE had resolution of high signal intensity on T2-weighted and FLAIR images (p < 0.01). Among patients who underwent head CT in the early period, none of the four with HHV-6 encephalopathy and six of the seven with HSE had abnormal findings, including parenchymal swelling, decreased attenuation of affected regions, and abnormal gyral enhancement (p < 0.05). CONCLUSION Serial MRI showed transient abnormal signal intensity in the mesial temporal lobes in patients with HHV-6 encephalopathy but persistent abnormal signal intensity in both the mesial temporal lobes and the extratemporal regions in patients with HSE. CT in the early period showed no abnormality in patients with HHV-6 encephalopathy but definite abnormal findings in patients with HSE. These differences may be useful in the differential diagnosis of the two conditions.

Radiation-associated changes in the length of telomeres in peripheral leukocytes from inpatients with cancer

Abstract Purpose: The telomere length of somatic cells shortens with age and with other endogenous and exogenous pathogenic factors. However, the effects of radiation therapy on telomere DNA of non-cancer tissue have not been thoroughly investigated. This study analyzed the telomere length of inpatients with cancer treated with radiation therapy to see whether the telomere lengths change in response to therapeutic radiation. Materials and methods: Twenty-five patients were enrolled in the study. The patients had lung cancer, prostate cancer, thyroid cancer, hepatoma, or rectal cancer. They received radiation therapy with a dose range of 15–74 Gy. The telomere lengths and telomere length distribution in peripheral leukocytes were analyzed by using a Southern blot-based method. Results: The telomere length and the telomere length distribution of the peripheral leukocytes did not change after radiation therapy. However, there was a significant proportional decrease in the short telomere fraction (< 4.4 kb) per day and per Gy. Conclusions: This observation suggested that the telomere length distribution of peripheral leukocytes could be affected by radiation therapy, and that the effect of radiation tends to appear in cells with short telomeres. Radiation therapy-associated somatic telomere length change within a short range of time, about three months or shorter, can be detected by analyzing the mean telomere length and telomere length distribution.

Prediction of outcome with FDG-PET in definitive chemoradiotherapy for esophageal cancer

The purpose of this study was to assess the efficacy of 18F-fluoro-2-deoxy-glucose uptake positron emission tomography (FDG-PET) for the prediction of outcome in definitive chemoradiotherapy (CRT) for esophageal cancer. We enrolled 56 patients with esophageal cancer treated with definitive CRT and examined by FDG-PET before treatment. We examined the correlation of the maximum standardized uptake value (SUVmax) in FDG-PET of the primary tumor with overall survival (OS), progression-free survival (PFS), local control (LC) and response of the primary tumor. After definitive CRT, 30 patients had a clinical complete response (CR), making the CR rate 54%. For all 56 patients, the 2-year OS rate, PFS rate and LC rates were 64%, 38% and 51%, respectively. We divided the patients into two groups according to SUVmax: SUVmax < 10 (low-SUV) and ≥10 (high-SUV). The 2-year OS rates in the low- and high-SUV groups were 100% and 41%, the PFS rates were 73% and 19%, the LC rates were 71% and 39%, and the CR rates were 100% and 32%, respectively. A univariate analysis revealed significant differences between the low- and high-SUV group in OS, PFS, LC and response (P = 0.0005, 0.0002, 0.048, and <0.0001, respectively). SUVmax and T stage were significantly associated with OS, PFS, LC and response. A multivariate analysis showed significant differences between the SUVmax <10 and ≥10 groups in overall survival and response (P < 0.05). Our result suggests that the SUVmax in FDG-PET of the primary tumor before treatment may have prognostic value for esophageal cancer.

Treatment Outcome of High-dose-rate Interstitial Radiation Therapy for Patients with Stage I and II Mobile Tongue Cancer

OBJECTIVES The aim of the study was to investigate the outcomes of high-dose-rate interstitial radiation therapy for patients with Stage I and II mobile tongue cancer retrospectively. METHODS Sixty-seven patients with Stage I and II mobile tongue cancer were treated with high-dose-rate interstitial radiation therapy, with or without external beam radiation therapy, between 1997 and 2007. The median dose of interstitial radiation therapy was 50 Gy in 10 fractions over 6 days. Thirty-five patients received external beam radiation therapy before interstitial radiation therapy. The median dose of external beam radiation therapy was 20 Gy delivered with single-lateral or bilateral fields, including the primary tumor site and upper jugular lymph nodes. Thirty-seven patients received concurrent chemotherapy, including carboplatin, cisplatin, fluorouracil or tegafur, gimeracil and oteracil (TS-1) systemically or with intra-arterial injection. Thirty-three patients received intratumoral injection of bleomycin before catheter insertion. The median follow-up time was 58.6 months (range 15.1-102.4 months). RESULTS The 5-year overall, cause-specific, progression-free survival rate and local control rate were 88.7, 92.1, 76.0 and 94.0%, respectively. Fourteen patients developed cervical lymph node recurrence, 11 of which were distributed within the external beam radiation therapy field. We found local failures in four cases within 2 years after the treatment and in three cases after >7 years, even though the latter were difficult to distinguish from second primary cancers. CONCLUSIONS The treatment results of our institutions were equivalent to previous reports. Most cervical lymph node metastases occurred within the external beam radiation therapy field, which implied that the external beam radiation therapy dose of 20-30 Gy was insufficient to prevent late cervical lymph node metastases.

Clinical results of definitive chemoradiotherapy for patients with synchronous head and neck squamous cell carcinoma and esophageal cancer.

Objectives:To assess the efficacy and toxicity of radical chemoradiotherapy for patients with synchronous head and neck squamous cell carcinoma (HNSCC) and esophageal cancer (EC). Methods:Thirty-four patients with synchronous HNSCC and EC were treated mainly with radical chemoradiotherapy at the same time. Median external radiation dose for HNSCC and EC was 70 Gy (range, 60–70.5 Gy), except for 2 patients with tongue cancer, who underwent brachytherapy and 60 Gy (range, 45–70 Gy), respectively. Thirty-one patients were treated with concurrent chemoradiotherapy with cisplatin and/or 5-fluorouracil or TS-1 (oral anticancer agent that combines tegafur, a metabolically activated prodrug of 5-fluorouracil, with 5-chloro-2, 4-dihydoroxypyridine, and potassium oxonate). Results:Thirty-three patients completed the intended treatment. The response rate was 94%, with 26 complete responses (76%) and 6 partial responses (18%). At a median follow-up of 17.3 months, 2-year rates of overall survival, cause-specific survival, and disease-free survival were 44%, 52%, and 33%, respectively. Initial failure patterns were local failure in 14 patients (63%), regional progression in 3 patients (13%), and distant metastasis in 6 patients (27%). The most common acute toxicity was myelosuppression, with 8 patients experiencing grade 3–4 toxicity. Three patients experienced grade 3 mucositis and pharyngitis. No patients experienced late morbidity of grade 3 or higher. Conclusions:Definitive chemoradiotherapy for patients with synchronous HNSCC and EC is feasible with a low mortality rate and acceptable morbidity.

Esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer: Frequency and prediction

PURPOSE To determine clinical factors for predicting the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer. METHODS AND MATERIALS The study group consisted of 109 patients with esophageal cancer of T1-4 and Stage I-III who were treated with definitive radiotherapy and achieved a complete response of their primary lesion at Kyushu University Hospital between January 1998 and December 2007. Esophageal stenosis was evaluated using esophagographic images within 3 months after completion of radiotherapy. We investigated the correlation between esophageal stenosis after radiotherapy and each of the clinical factors with regard to tumors and therapy. For validation of the correlative factors for esophageal stenosis, an artificial neural network was used to predict the esophageal stenotic ratio. RESULTS Esophageal stenosis tended to be more severe and more frequent in T3-4 cases than in T1-2 cases. Esophageal stenosis in cases with full circumference involvement tended to be more severe and more frequent than that in cases without full circumference involvement. Increases in wall thickness tended to be associated with increases in esophageal stenosis severity and frequency. In the multivariate analysis, T stage, extent of involved circumference, and wall thickness of the tumor region were significantly correlated to esophageal stenosis (p = 0.031, p < 0.0001, and p = 0.0011, respectively). The esophageal stenotic ratio predicted by the artificial neural network, which learned these three factors, was significantly correlated to the actual observed stenotic ratio, with a correlation coefficient of 0.864 (p < 0.001). CONCLUSION Our study suggested that T stage, extent of involved circumference, and esophageal wall thickness of the tumor region were useful to predict the frequency and severity of esophageal stenosis associated with tumor regression in radiotherapy for esophageal cancer.

A case of gastric plexiform fibromyxoma: Radiological and pathological findings

Plexiform fibromyxoma is a relatively new pathological category that consists of a rare group of non-gastrointestinal stromal tumors with a peculiar plexiform growth pattern. We report a case of gastric plexiform fibromyxoma in a 60-year-old man. Gastroscopic examination revealed a gastric submucosal tumor in the antrum. Magnetic resonance imaging (MRI) showed a nodule with distinct signal hyperintensity on T2-weighted images, with strong enhancement peripherally in the early phase to the entire lesion in the delayed phase. Endoscopic ultrasound-guided fine-needle aspiration cytology was performed, and the cytological diagnosis was spindle cell tumor, so partial gastrectomy was performed under a preoperative diagnosis of GIST. The resected tumor demonstrated plexiform architecture, myxoid stroma, prominent vasculature, and spindle cells, reflecting the characteristic findings on MRI. This is the first report to describe radiological findings for gastric plexiform fibromyxoma.

Can a belly board reduce respiratory-induced prostate motion in the prone position? - Assessed by cine-magnetic resonance imaging

The purpose of this study is to evaluate the real-time respiratory motion of the prostate and surrounding tissues/organs in the supine and prone positions and to investigate, using cine-MRI, whether a belly board can reduce respiratory-induced motion in the prone position. Cine-MRI scans were made of 13 volunteers in the supine and prone positions on a flat board and in two different prone positions using a belly board. Images in cine mode were recorded for 20 seconds. For each session, the points of interest (POIs) were located at the apex, base, mid-anterior surface and mid-posterior surface of the prostate; the tip of the seminal vesicle; the pubic symphysis; and the sacrum. The maximum range and standard deviation (SD) of the displacement from the mean value were calculated. The SDs for each of the four different positions were compared using a paired t-test. Respiratory-induced prostate motion was significantly larger in the prone position than in the supine position. However, when a belly board was used in the prone position, motion in the prostate and surrounding tissues/organs was significantly reduced. There were no significant differences between the two different positions using a belly board in any of the POIs.

Carboplatin and etoposide combined with radiotherapy for limited-stage small-cell esophageal carcinoma: three cases and review of the literature

PurposeSmall-cell esophageal carcinoma (SCEC) is a rare disease for which standard therapy has not yet been established. We report the results of three cases of limited-stage SCEC treated with combination therapy using carboplatin (CBDCA) and etoposide (VP-16) and radiotherapy.Materials and methodsThe clinical stage according to the Japanese Classification of Esophageal Cancer 7th ed. was stage III in 2 cases and stage IVa in 1. These patients with limited-stage SCEC were treated at our institution with four cycles of CBDCA and VP-16, either concurrent with radiotherapy for the second two cycles (n = 2) or followed by radiotherapy after the last cycle (n = 1).ResultsA complete response (CR) was obtained for all three patients, resulting in a response rate of 100%. Two patients are alive at 16.4 and 22.5 months after initial treatment. One patient died with myeloid leukemia at 43.5 months after initial treatment. None of the patients had loco-regional recurrence. Brain metastasis was detected in one patient at 7 months after initial therapy and was treated with stereotactic radiotherapy combined with whole brain irradiation.ConclusionCBDCA and VP-16 in combination with radiotherapy should be considered an important treatment option for SCEC.

Spontaneous pneumothorax after stereotactic radiotherapy for non-small-cell lung cancer

The report presented here describes a case of spontaneous pneumothorax observed after stereotactic radiotherapy (SRT) for non-small-cell lung cancer (NSCLC). An 84-year-old man with a Stage IIB, T3N0M0 NSCLC in the right upper lobe and a Stage IA NSCLC in the right lower lobe of the lung was treated with SRT for both tumors. He received SRT with a total dose of 60.0 Gy in 10 fractions delivered to the right upper lobe, and 48.0 Gy in 4 fractions delivered to the right lower lobe. Two months after completion of the treatment, he developed spontaneous pneumothorax. He was asymptomatic and recovered with conservative management. Spontaneous pneumothorax has occasionally been reported to occur following thoracic radiotherapy for malignancy. Almost all of the reported cases are patients who had received mantle irradiation for Hodgkin’s disease. We have been unable to fi nd any reports of spontaneous pneumothorax after SRT, which has recently been used for treating patients with early-stage NSCLC. Because a case of spontaneous pneumothorax after SRT was observed in our institution, its clinical course is described here along with a discussion of possible causes of spontaneous pneumothorax.