Akira Anbai

Diffusion changes in a tumor and peritumoral tissue after stereotactic irradiation for brain tumors: possible prediction of treatment response.

Objective: Changes in apparent diffusion coefficient (ADC) in a tumor and peritumoral tissue after stereotactic irradiation (STI) were evaluated, and then the therapeutic efficacy of ADC measurement was assessed. Methods: In 20 tumors, diffusion-weighted imaging within 1 week before and 2-4 weeks after STI was performed. The normalized ADC (nADC) was measured. The nADCs in the tumor and peritumoral region before STI were compared with those after STI and the change in tumor nADC compared with the change in tumor size. Results: The nADC of the tumors was significantly higher 2-4 weeks after STI compared with that before STI. The nADC of the peritumoral regions 2-4 weeks after STI did not differ significantly from that before STI. A significant difference in the nADC at 2-4 weeks after STI was observed between the responder and nonresponder groups. Conclusions: Changes in nADC as measured by diffusion-weighted imaging can predict response to STI.

High-dose-rate Intracavitary Brachytherapy Combined with External Beam Radiotherapy for Stage IIIb Adenocarcinoma of the Uterine Cervix in Japan: A Multi-Institutional Study of Japanese Society of Therapeutic Radiology and Oncology 2006–2007 (Study of JASTRO 2006–2007)

OBJECTIVE The current study was a retrospective questionnaire survey of stage IIIb adenocarcinoma of the uterine cervix treated with high-dose-rate intracavitary brachytherapy combined with external beam radiation therapy in Japan aimed to investigate the optimal dose on the basis of the biological effective dose and prognostic factors. METHODS Between 1990 and 2000, 61 patients with stage IIIb adenocarcinoma of the uterine cervix underwent high-dose-rate intracavitary brachytherapy combined with external beam radiation therapy in 19 major hospitals in Japan. This retrospective questionnaire survey was performed by mail including survey charts to be fulfilled by radiation oncologists in these 19 major hospital. Fifty had only adenocarcinoma components and 11 had adenosquamous cell carcinoma components. All patients were treated with high-dose-rate intracavitary brachytherapy combined with external beam radiation therapy. Total biological effective dose (T-BED(10)) was calculated from the sum of the biological effective doses of the external beam radiation therapy and the intracavitary brachytherapy. Thirty-two patients underwent chemotherapy. RESULTS The 5-year overall survival rate of all patients was 20.2%. Stratified by total biological effective dose, the 5-year overall survival rate was 0% for T-BED(10) <75 Gy, 24.7% for T-BED(10) between 75 and 100 Gy and 0% for T-BED(10) >110 Gy (P = 0.15). Stratified by histopathology, the 5-year overall survival rate was 22.1% for adenocarcinoma and 13.6% for adenosquamous cell carcinoma (P = 0.43). Stratified by chemotherapy, the 5-year overall survival rate was 20.3% in patients who received chemotherapy and 20.4% in patients who did not receive chemotherapy (P = 0.96). CONCLUSIONS The 5-year overall survival rate of stage IIIb adenocarcinoma of the uterine cervix in this retrospective questionnaire survey was 20.2%. The optimal T-BED(10) and evident prognostic factors were not clear from this questionnaire survey.

Therapeutic strategy for the treatment of postoperative recurrence of esophageal squamous cell carcinoma: clinical efficacy of radiotherapy.

We investigated the effectiveness of chemoradiotherapy for the treatment of lymph node recurrence and hematogenous metastasis after esophagectomy for esophageal squamous cell carcinoma. Between 2001 and 2006, 216 patients with thoracic esophageal squamous cell carcinoma had curative esophagectomy. Of those, 23 with lymph node recurrence received chemoradiotherapy (50.0-68.8 Gy). In addition, five patients had isolated recurrences in a distant organ and received chemoradiotherapy (50.0-60.0 Gy). We analyzed outcomes from the radiotherapy for recurrent esophageal cancer. The 1-, 2-, and 5-year survival rates after recurrence for the 23 patients whose lymph node recurrence was treated with chemoradiotherapy were 52, 31, and 24%, respectively, and the median survival time was 13 months. Among the five patients with recurrent tumors in a distant organ, chemoradiotherapy produced a complete response in two patients, a partial response in one patient, and stable disease in two patients, giving an effectiveness rate of 60% (complete response + partial response). Chemoradiotherapy has a beneficial prognostic effect in patients with lymph node recurrence of esophageal squamous cell carcinoma. Chemoradiotherapy for a metastatic tumor in a distant organ may be the treatment of choice in cases where systemic chemotherapy has proven ineffective.

Thallium-201 SPECT in the evaluation of early effects on brain tumors treated with stereotactic irradiation.

Purpose: To determine whether thallium-201 SPECT can predict response to stereotactic irradiation (STI) earlier than magnetic resonance imaging (MRI), the change in tumor size measured by MRI was compared with the change in tumor activity measured by Tl-201 SPECT before and after STI. Materials and Methods: Twenty-one tumors in 16 patients with intracranial tumors were treated by STI. Tl-201 SPECT was performed within 1 week before the beginning of STI and within 1 week after the end of STI in all patients. All patients underwent MRI within 1 week before the beginning of STI, and 14 patients (19 tumors) underwent MRI within 1 week after the end of STI. Follow-up MRI was performed 1 to 2 months after the end of STI in 14 patients (16 tumors). The activity of Tl-201 in the tumor divided by that of the uninvolved symmetric area was defined as the Tl-index. The change in tumor size immediately and 1 to 2 months after STI was compared with the change in Tl-index immediately after STI. Results: No significant relationship between the ratio of tumor size immediately after STI and the ratio of Tl-index immediately after STI was found. A significant correlation (r = 0.69, P <0.05) between the ratio of tumor size 1 to 2 months after STI and the ratio of Tl-index immediately after STI was found. Conclusions: This study suggests that Tl-201 SPECT immediately after STI can predict treatment response 1 to 2 months after STI, and that Tl-201 SPECT can be an early indicator of treatment response.

Two cases of cisplatin-induced permanent renal failure following neoadjuvant chemotherapy for esophageal cancer

Highlights • Two esophageal cancer patients developed severe acute renal failure after neoadjuvant chemotherapy with cisplatin and 5-fluorourasil.• Volume expansion remains the most effective strategy for prevention of cisplatin nephrotoxicity.• The two patients described here received sufficient drip infusion and produced good urine volumes.• In both cases, renal biopsy examination indicated partial recovery of the proximal tubule, but renal function did not recover.

Impact of oxygen status on 10B-BPA uptake into human glioblastoma cells, referring to significance in boron neutron capture therapy

Abstract Boron neutron capture therapy (BNCT) can potentially deliver high linear energy transfer particles to tumor cells without causing severe damage to surrounding normal tissue, and may thus be beneficial for cases with characteristics of infiltrative growth, which need a wider irradiation field, such as glioblastoma multiforme. Hypoxia is an important factor contributing to resistance to anticancer therapies such as radiotherapy and chemotherapy. In this study, we investigated the impact of oxygen status on 10B uptake in glioblastoma cells in vitro in order to evaluate the potential impact of local hypoxia on BNCT. T98G and A172 glioblastoma cells were used in the present study, and we examined the influence of oxygen concentration on cell viability, mRNA expression of L-amino acid transporter 1 (LAT1), and the uptake amount of 10B-BPA. T98G and A172 glioblastoma cells became quiescent after 72 h under 1% hypoxia but remained viable. Uptake of 10B-BPA, which is one of the agents for BNCT in clinical use, decreased linearly as oxygen levels were reduced from 20% through to 10%, 3% and 1%. Hypoxia with <10% O2 significantly decreased mRNA expression of LAT1 in both cell lines, indicating that reduced uptake of 10B-BPA in glioblastoma in hypoxic conditions may be due to reduced expression of this important transporter protein. Hypoxia inhibits 10B-BPA uptake in glioblastoma cells in a linear fashion, meaning that approaches to overcoming local tumor hypoxia may be an effective method of improving the success of BNCT treatment.

Treatment Outcomes of Chemoradiotherapy for Patients with Advanced Esophageal Cancer

Purpose: To evaluate the treatment outcomes of chemoradiotherapy for patients with advanced esophageal cancer and estimate the prognostic factors. Materials and methods: Patients with advanced esophageal cancer, who were treated with chemoradiotherapy (CRT) between April 2003 and December 2010, were evaluated. Patients received concurrent chemoradiotherapy (cisplatin plus 5-fluorouracil and 61.2 Gy radiotherapy). Therapeutic response, overall survival time, and toxicity were examined and statistical evaluation was performed. Results: One hundred and fourteen patients were treated with CRT. Among them, 84 patients (77.2%) received the complete course of CRT. Eighteen patients (15.8%) had a complete response, 90 patients (78.9%) had a partial response and 6 patients (5.3%) exhibited progressive disease. The mean follow-up period was 14.6 months (range, 2-90 months). The median overall survival time was 13.0 months. The 2-year and 3-year overall survival rates were 38.1% and 19.2%, respectively. Severe hematological toxicities included Grade 3 leukopenia in 40 patients (35.1%). Treatment-related death was estimated to have occurred in 7 patients. Performance status and body weight loss were identified as significant prognostic factors. Conclusion: In our study, PS and body weight loss showed prognostic factors in CRT for advanced esophageal cancer.