Shintaro Shirai

High-dose-rate brachytherapy of a single implant with two fractions combined with external beam radiotherapy for hormone-naive prostate cancer.

PURPOSE To evaluate the preliminary outcomes of high-dose-rate (HDR) brachytherapy of a single implant with two fractions and external beam radiotherapy (EBRT) for hormone-naive prostate cancer. METHODS AND MATERIALS Between March 2000 and Sept 2003, a total of 53 patients with tumor Stage T1c-T3b N0 M0 prostate cancer were treated with HDR brachytherapy boost doses (7.5 Gy/fraction) and 50-Gy EBRT during a 5.5-week period. Median follow-up was 61 months. Patients were divided into groups with localized (T1c-T2b) and advanced disease (T3a-T3b). We used the American Society for Therapeutic Radiology and Oncology (ASTRO) definition for biochemical failure. According to recommendations of the Radiation Therapy Oncology Group-ASTRO Phoenix Consensus Conference, biochemical failure-free control rates (BF-FCRs) at 3 years were investigated as 2 years short of the median follow-up. RESULTS Between April 2000 and Sept 2007, Common Terminology Criteria for Adverse Events Version 2.0 late Grade 2 genitourinary and gastrointestinal toxicity rates were 0% and 3.8%, respectively. Erectile preservation was 25% at 5 years. Overall survival was 88.1% and cause-specific survival was 100%. At 3 years, ASTRO BF-FCRs of the localized and advanced groups were 100% and 42%, respectively (p = 0.001). CONCLUSIONS The HDR brachytherapy of a single implant with two fractions plus EBRT is effective in treating patients with localized hormone-naive prostate cancer, with the least genitourinary and gastrointestinal toxicities; however, longer median BF-FCR follow-up is required to assess these findings.

Feasibility and efficacy of single photon emission computed tomography-based three-dimensional conformal radiotherapy for hepatocellular carcinoma 8 cm or more with portal vein tumor thrombus in combination with transcatheter arterial chemoembolization.

PURPOSE To assess the feasibility and efficacy of single photon emission computed tomography-based three-dimensional conformal radiotherapy (SPECT-B 3D-CRT) for large hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). METHODS AND MATERIALS HCC patients with PVTT in the first branch or main trunk, 8 cm or greater in size, were admitted to the study. SPECT, using Tc-99m-galactosyl human serum albumin, was used in radiation treatment planning to explore the optimal irradiation beam angle. SPECT enabled the minimum possible irradiation of functional liver (FL). Clinical target volume (CTV) included the main tumor and PVTT. SPECT-B 3D-CRT targeted the CTV to a total dose of 45 Gy/18 fractions. HCC outside the CTV was treated by transcatheter arterial chemoembolization (TACE). RESULTS Nineteen cases were enrolled in this study. The mean maximum dimension, mean CTV, and mean dose to FL were 11.0 cm (range, 8.0-20.0), 435 cm(3) (range, 60-2,535), and 1,102 cGy (range, 691-1,695), respectively. Follow-up SPECT demonstrated radiation-induced dysfunctional liver. Despite the inclusion of 6 cases of Child-Pugh B or C, no patients experienced Grade 3 or worse radiation-induced liver disease. The cumulative non-progression rates of PVTT and PVTT plus main tumor were 78.0 and 43.2%, respectively. Survival rates at 1 and 2 years were 47.4 and 23.7%, respectively. CONCLUSIONS SPECT-B 3D-CRT with TACE appears to be tolerable to cirrhotic liver and to provide promising prognosis for patients with HCC sized 8 cm or more, in comparison with previous treatment methods. A longer follow-up period is required to evaluate these findings.

Reirradiation of prostate cancer with rectum preservation: eradicative high-dose-rate brachytherapy with natural type hyaluronate injection.

INTRODUCTION Reirradiation of locally recurrent prostate cancer after radiotherapy is limited because of its toxicity to the rectum that is closely adjacent to the prostate. To solve geometric anatomic constraints, including rectal size and distance from the prostate, we developed a technique that modifies the geometry by noninvasive direct intervention. METHODS AND MATERIALS In a patient with local recurrence of prostate cancer at 18 months after initial radiotherapy of 61.8 GyE(LQ2,3) (gray equivalent in 2 Gy/fraction at α/β=3 calculated with linear quadratic [LQ] model) to the prostate, we prescribed 16 Gy (60.8 GyE(LQ2,3) or 78.2 GyE(LQ2,1.6)) of reirradiation by high-dose-rate brachytherapy, using a bolus injection of native-type hyaluronate to create and maintain a distance between the prostate and the rectum and decrease rectal size during treatment. RESULTS The procedure was achieved in 10min, without complications. Rectal D(2cc) of the reirradiation was 5.58 Gy (9.58 GyE(LQ2,3)). Compared with the initial radiation, the gel injection resulted in an improved therapeutic ratio. The patient was regularly followed up at our clinic; at over 3.5 years after reirradiation, there was no evidence of recurrence or radiation-related toxicities greater than Grade 2, maintaining a nadir prostate-specific antigen level of 0.03 ng/mL without hormonal therapy. CONCLUSION We consider that this technique is useful for achieving safe and curative reirradiation of prostate cancer.

Prospective comparison of transcatheter arterial chemoembolization with Lipiodol-epirubicin and Lipiodol-cisplatin for treatment of recurrent hepatocellular carcinoma

PurposeThe aim of this study was to compare the safety and short-term efficacy of transcatheter arterial chemoembolization (TACE) using cisplatin-Lipiodol suspension (CP/Lp) with that using epirubicin-Lipiodol emulsion (EP/Lp) in patients with recurrent hepatocellular carcinoma (HCC).Materials and methodsA total of 28 HCC patients were enrolled prospectively and assigned to the CP/Lp group or EP/Lp group. Adverse effects related to TACE were graded; and the treatment effect (TE) on HCC nodules at 3 months and overall tumor response at 6 months were assessed as the endpoint.ResultsNo significant difference was observed between the groups regarding the frequency of adverse effects of grade 3 or less. The TE rates for 100% necrosis plus >50% necrosis in 62 HCC nodules in the CP/Lp group and 75 HCC nodules in the EP/Lp group were 72.6% and 66.7%, respectively (P = 0.894). Overall tumor response revealed that six patients (50.0%) in the CP/Lp group and six patients (37.5%) in the EP/Lp group had a partial response plus a complete response, with no significant difference (P = 0.615). TACE-free control curves for both groups revealed no significant difference (P = 0.513).ConclusionNo significant difference was found with regard to adverse effects, the treatment effect on HCC nodules, or overall tumor response between the CP/Lp and EP/Lp groups.

SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY-BASED THREE-DIMENSIONAL CONFORMAL RADIOTHERAPY FOR HEPATOCELLULAR CARCINOMA WITH PORTAL VEIN TUMOR THROMBUS

PURPOSE To evaluate the safety and efficacy of three-dimensional conformal radiotherapy (3D-CRT) using single photon emission computed tomography (SPECT) in unresectable hepatocellular carcinoma (HCC) with portal vein tumor thrombus (PVTT). METHODS AND MATERIALS Patients with HCC with PVTT in the first branch and/or main trunk were selected for this study. The optimal beam directions for 3D-CRT were explored using a Tc-99m-galactosyl human serum albumin SPECT image for guidance. The SPECT image was classified as either wedge type or localized type. The clinical target volume to a total dose of 45 or 50 Gy per 18-20 fractions included the main tumor and PVTT in the wedge type and PVTT alone in the localized type. RESULTS Twenty-six patients were enrolled: 18 with wedge type and 8 with localized type. Mean tumor size was 7.1 cm (range, 4.4-12.3 cm). Clinical target volumes of wedge type vs. localized type were 111.2 cm(3) vs. 48.4 cm(3) (p = 0.010), respectively. Mean dose to normal liver and mean dose to functional liver were 1185 cGy and 988 cGy (p = 0.001) in wedge type and 1046 cGy and 1043 cGy (p = 0.658) in localized type, respectively. Despite an incidence of Child-Pugh B and C of 57.7%, no patients experienced radiation-induced liver disease. The progression of PVTT was inhibited, with an incidence of 92.2%; survival rates at 1 and 2 years were 44% and 30%, respectively. CONCLUSION Single photon emission computed tomography-based 3D-CRT enables irradiation of both the main tumor and PVTT with low toxicity and promising survival.

Large cell neuroendocrine carcinoma of the gallbladder: long survival achieved by multimodal treatment

Large cell neuroendocrine carcinoma of the gall-bladder is a rare disease in which the prognosis worsens with size. We report a case of large cell neuroendocrine carcinoma of the gallbladder in a 64-year-old woman who presented with a right upper quadrant mass whose longest diameter was 11.5 cm; the mass was initially considered to be unresectable because of probable invasion to the main portal vein and biliary tract. The patient received multi-modal treatment, consisting of intraarterial chemotherapy, three-dimensional radiation therapy, right trisegmentectomy, and γ-knife irradiation (for brain metastases). She has survived for 69 months since the initial diagnosis and has shown no signs of recurrence at 35 months after the last γ-knife irradiation for brain metastases. This result suggests that multimodal treatment including surgery, chemotherapy, and radiation therapy achieved a good response and led to long survival.

Effectiveness of Hepatic Arterial Embolization on Radiofrequency Ablation Volume in a Swine Model: Relationship to Portal Venous Flow and Liver Parenchymal Pressure

PURPOSE To evaluate the effectiveness of transcatheter arterial embolization (TAE) on radiofrequency (RF) ablation volume and compare portal vein (PV) flow and liver parenchymal pressure before and after treatment. MATERIALS AND METHODS Eight healthy female swine were divided into four groups to be treated with RF ablation alone (RF-only group), RF ablation after TAE with gelatin sponge particles (GSPs; RF/TAE group), RF ablation after TAE with Lipiodol plus GSPs (RF/TAE/Lipiodol group), and PV embolization (PVE) with GSPs after TAE with Lipiodol plus GSPs (RF/TAE/Lipiodol/PVE group). Five ablations were created in each swine, with 10 ablations per group. A 2-cm expandable LeVeen needle electrode was used for RF ablation. RESULTS The greatest ablation volume (18,410.1 mm(3) +/- 3,986.4) was observed in the RF/TAE/Lipiodol/PVE group. Of the RF-only, RF/TAE, and RF/TAE/Lipiodol groups, the RF/TAE/Lipiodol group (14,835.5 mm(3) +/- 2,743.2) had a significantly larger ablation volume than the RF-only (8,002.6 mm(3) +/- 2,788.3) and RF/TAE groups (10,398.5 mm(3) +/- 2965.8; P < .05/3). PV pressures increased significantly after TAE (P < .01) compared with the pressure before TAE in the RF/TAE/Lipiodol and RF/TAE/Lipiodol/PVE groups, but not in the RF/TAE group. A marked increase in liver parenchymal pressure was seen during RF ablation; however, there were no significant differences among groups. Accumulation of Lipiodol was noted in the sinusoids in the RF/TAE/Lipiodol and RF/TAE/Lipiodol/PVE groups. CONCLUSIONS TAE with blockade of PV flow before RF ablation was associated with greater ablation volumes. Liver parenchymal pressure showed no correlation with increased ablation volume.

Differentiation of pancreatic serous cystadenoma from endocrine tumor and intraductal papillary mucinous neoplasm based on washout pattern on multiphase CT.

Objective To evaluate the washout (WO) pattern of serous cystadenomas (SCAs) compared with endocrine tumors (ETs) and intraductal papillary mucinous neoplasm (IPMN). Methods Patients with serous cystadenoma (n = 12), ET (n = 29), and IPMN (n = 35) underwent 4-phase computed tomography CT. Tumors were categorized as hyperdense or hypodense. Computed tomographic values measured were unenhanced attenuation (AU), pancreatic attenuation (A12, 12 seconds), portal attenuation (A35), and equilibrium (A158). Computed tomographic parameters calculated were wash-in (WI) = A12 − AU; WO = A12 − A35; and washout ratio (WOR) = WO/WI × 100/22. Results Hyperdense SCAs had significantly higher WOR than did hyperdense ETs (P = 0.001). Among the 3 hypodense tumors, SCAs had the significantly highest WOR (P < 0.05/3). Relative to the pancreas, the WOR of SCAs were equivalent, whereas the WOR of ETs and IPMNs were significantly lower. Conclusions Hyperdense SCAs had significantly higher WOR than did hyperdense ETs, and hypodense SCAs had the significantly highest WOR among the three.

CRITICAL ORGAN PRESERVATION IN REIRRADIATION BRACHYTHERAPY BY INJECTABLE SPACER

PURPOSE This case series study evaluated the feasibility and effectiveness of an interstitial high-dose rate brachytherapy (HDR-BT) procedure combined with an at-risk organ-sparing procedure. METHODS AND MATERIALS Thirty patients who were scheduled for reirradiation treatment for recurrent cancer after receiving a median dose of 60 Gy (range, 44-70 Gy) in 2-Gy fractions of previous external beam treatment were enrolled. Thirteen patients had lesions in the head and neck, and other lesions were located in the axilla, skeleton, breast, pelvis, and abdominal wall. Chief complaints included local masses (for 25) and refractory pain (for 21). After high-dose rate brachytherapy applicator needle implantation, an optimal CT-based three-dimensional brachytherapy plan was created with a virtual at-risk organ shift from the target. According to the plan, hyaluronic acid gel was injected to maintain the shift during irradiation. The prescribed dose was the result of an individualized tradeoff between target dose and at-risk organ dose, to avoid serious complications. A single-fraction dose of 18.0 Gy (median, equivalent to 75.6 Gy at an alpha/beta value of 3; range, 16-20 Gy) was applied to the tumor. RESULTS The at-risk organ dose decreased from 9.1 +/- 0.9 Gy to 4.4 +/- 0.4 Gy (mean +/- standard deviation, p < 0.01), and the normal tissue complication probability decreased from 60.8% +/- 12.6% to 16.1% +/- 19.8% (p < 0.01). The shift effect lasted at least 4 hours and disappeared gradually. Distinct tumor shrinkage in 20 of 21 eligible patients, including tumor disappearance in 6 patients, pain reduction in 18 of 21 eligible patients, and no unexpected late toxicity greater than grade 2 were observed during the 19.5-month observation period. CONCLUSIONS This at-risk organ-sparing preservation procedure may provide a safe and efficient reirradiation treatment.

Interfractional fluctuation of rectal dose in high dose rate brachytherapy for prostate cancer.

PurposeThe aim of the study was to explore the cause of the difference in the maximal rectal dose between the first and second high dose rate (HDR) brachytherapy applications by comparing the thickness of the anterior rectal wall.Materials and methodsThe rectal dose and the thickness of the anterior rectal wall were analyzed in 26 patients with prostate cancer. After undergoing external beam radiation treatment with a total isocenter dose of 50 Gy, they were treated with HDR brachytherapy of 7.5 Gy/fraction, two fractions daily. The interval between the first HDR brachytherapy session and the second was 5 h. The rectal doses were directly surveyed during irradiation of the HDR brachytherapy. Thickening of the anterior rectal wall was measured at the same level by axial computed tomography scans obtained before the first and second HDR brachytherapy applications.ResultsThe maximal surveyed rectal doses during the first and second HDR brachytherapy applications were 188 ± 51 cGy and 220 ± 35 cGy, respectively (P < 0.01). The fluctuation ratio exceeded 1 in each case. The thickness of the anterior rectal wall before the first and second HDR brachytherapy applications was 18.78 ± 4.34 mm and 14.95 ± 4.09 mm (P < 0.01), respectively. The fluctuation difference exceeded 0 in each case.ConclusionThe different rectal dose is attributable to thinning of the anterior rectal wall. The total rectal dose is within the range of doses at risk of exerting a toxic effect on the rectum.