伊藤 文隆

INTRODUCTION: Radiotherapy is a treatment option in the management of patients with metastatic liver disease. The aim in this case was to evaluate radiation-induced dysfunctional liver lesions using 99mTc-GSA-SPECT, Gd-EOB-DTPA-enhanced MRI, and radiation dose distribution in a patient after radiation therapy. PRESENTATION OF CASE: After sigmoid colon resection, three liver metastases were treated with radiotherapy at the same time. Liver function after radiotherapy was determined to be A according to the Child-Turcott-Pugh classification. 99mTc-GSA-SPECT showed a wider reduction in uptake than Gd-EOB-DTPA MRI at all three sites. HH15 showed decreased liver function. DISCUSSION: In the 99mTc-GSA-SPECT and Gd-EOB-DTPA MRI hepatocyte phases, residual signals of normal hepatocytes were observed despite irradiation at three sites. Additional treatment could be considered for the two recurrent lesions because there was no deterioration of liver function in post-irradiation imaging findings and blood sampling. CONCLUSION: 99mTc-GSA-SPECT and EOB-MRI showed characteristic findings for evaluation of liver function after radiotherapy for multiple liver metastases, suggesting the need for both imaging evaluations. It is now possible to choose whether to perform local additional treatment (additional radiation, RFA) or other chemotherapy for liver metastases after recurrence.

Central nervous system (CNS) involvement in anaplastic large cell lymphoma (ALCL) at diagnosis is rare and leads to poor prognosis with the use of the standard ALCL99 protocol alone. CNS-directed intensive chemotherapy, such as an increased dose of intravenous MTX, increased dose of dexamethasone, intensified intrathecal therapy, and high-dose cytarabine, followed by cranial irradiation, has been shown to improve survival in this population. In this paper, the authors describe a 14-year-old male with an intracranial ALCL mass at onset who received CNS-directed chemotherapy followed by 23.4 Gy of whole-brain irradiation. After the first systemic relapse, the CNS-penetrating ALK inhibitor, alectinib, was applied; it has successfully maintained remission for 18 months without any adverse events. CNS-penetrating ALK inhibitor therapy might prevent CNS relapse in pediatric ALK-positive ALCL. Next-generation ALK inhibitors could be introduced as a promising treatment option, even for primary ALCL with CNS involvement, which could lead to the omission of cranial irradiation and avoid radiation-induced sequalae. Further evidence of CNS-penetrating ALK inhibitor combined therapy for primary ALK-positive ALCL is warranted to reduce radiation-induced sequalae in future treatments.

The purpose of this study was to determine the most appropriate seed arrangement by comparing two different methods (linked seeds and loose seeds). A total of sixty-one patients (28 linked seed brachytherapy cases and 33 loose seed brachytherapy cases) with clinically localized prostate cancer were treated with I-125 permanent prostate brachytherapy. Modified peripheral loading was the method used for seed placement. The parameters evaluated were as follows: prostate D90, V100, and V150; urethral D90, D10, and D5; and rectal V100 (RV100) and D2 (RD2). Coefficient parameters (r and r2) were assessed by regression analysis. Prostate V150, urethral D90, urethral D10, urethral D5, and RD2 showed significant correlations between both methods in all patients. Urethral D90, urethral D10, urethral D5, and RD2 showed significant correlations in patients who received linked seed brachytherapy. Prostate V150, urethral D90, urethral D10, urethral D5, RV100, and RD2 showed significant correlations in patients who received loose seed brachytherapy. Urethral D90, urethral D10, urethral D5, and RD2 showed significant correlations in the linked seed and loose seed brachytherapy analyses. In contrast, prostate D90 and prostate V100 showed no correlation. Parameters of normal organ damage showed good correlations between intraplan and postplan parameters. These parameters may be useful to determine normal organ damage during guided brachytherapy with two different methods (linked seeds and loose seeds).

Although concurrent chemoradiotherapy (CCRT) is an effective treatment for advanced cervical cancer, its use in advanced cervical cancer with a pedunculated cervical leiomyoma remains challenging. The prognosis of recurrent cervical cancer is poor, with a low possibility of complete response (CR). In this present study, after completion of external beam radiotherapy (EBRT) and chemotherapy (weekly cisplatin), we performed the resection of a pedunculated cervical leiomyoma. No malignant cells were identified in the pathological specimen. After the myoma resection, no cervical tumor was observed on follow-up magnetic resonance imaging (MRI). High-dose-rate intracavitary brachytherapy (HDR-ICBT) was also performed. Local control of the cervical tumor was achieved after 30 months of treatment. After CCRT, rectal hemorrhage was observed but was effectively controlled via local intervention. Twenty-four months after CCRT, the patient was given salvage chemotherapy (paclitaxel plus carboplatin) due to lymph node metastasis observed at the outside range of EBRT. Thirty months after CCRT, computed tomography showed that the metastatic lymph nodes had disappeared, and the patient achieved CR. Thus, for advanced cervical cancer with a pedunculated cervical leiomyoma, CCRT could be completed following myoma resection. In addition, salvage chemotherapy for lymph node metastasis might result in CR. In this present case, a gastrointestinal adverse event was observed after radiotherapy and salvage chemotherapy with paclitaxel plus carboplatin achieved CR.

PURPOSE: The incidence of secondary bladder cancer after treatment for localized prostate cancer (PCa) remains unclear. In this study, PCa cases treated with brachytherapy (BT) were evaluated to assess the incidence of a second malignancy of bladder cancer in a Japanese cohort. MATERIALS AND METHODS: Overall, 969 patients treated with BT at our hospital between July 2006 and January 2019 were included in the study cohort. The incidence and predictors of secondary bladder cancer were also assessed. RESULTS: The incidence of secondary bladder cancer was 1.5% (n = 14). Of the seven factors (age, pretreatment PSA, Gleason score, cTNM stage, prostate volume, total activity, and combined external beam), prostate volume and total activity showed significant differences between the cohorts with and without secondary bladder cancer (P = .03 and P = .001, respectively). Upon comparison of the seven parameters for the 969 patients treated with BT, we found that only the total activity factor was affected by the incidence of secondary bladder cancer in the multivariate analysis (P = .007). CONCLUSION: The incidence of secondary bladder cancer was evaluated after BT for PCa. Total activity was associated with the incidence of secondary bladder cancer in Japanese patients who received BT.

BACKGROUND: Investigating oncological outcomes in patients registered in the Japanese Prostate Cancer Outcome Study of Permanent Iodine-125 Seed Implantation (J-POPS) in terms of biochemical relapse-free survival (bRFS) by the Phoenix and the newly developed J-POPS definitions, exploration of predictive factors for bRFS, and preliminary verification of pitfalls of prostate-specific antigen (PSA) failure definitions. METHODS: Between July 2005 and June 2007, 2316 clinically localized patients underwent permanent seed implantation. The primary endpoint was bRFS. One of the secondary endpoints was overall survival (OS). RESULTS: The median age was 69 and performance status was 0 in 99.1% of participants. The median biologically effective dose (BED) was about 180 Gy2. During a median follow-up of 60.0 months, 8.4 and 5.9% had PSA failure by the Phoenix and the J-POPS definitions, respectively. The 5-year bRFSs based on the Phoenix and the J-POPS definitions were 89.1 and 91.6%, respectively. The 5-year OS was 97.3%. According to multivariate analyses, only age affected bRFS based on the Phoenix definition, whereas the risk group and BED independently affected bRFS based on the J-POPS definition. A spontaneous PSA decrease was seen in 91.1% of participants after PSA failure based on the Phoenix definition alone, but in only 22.2% after PSA failure based on the J-POPS definition alone. CONCLUSION: The world's largest registration study, J-POPS, consisted of patients with longevity, and a highly quality-controlled BED resulted in excellent bRFS and OS. The high likelihood of PSA bounce by the Phoenix definition should be taken into account, especially in younger patients. CLINICAL TRIAL INFORMATION: NCT00534196.

症例は71歳男性で、5年前に右咽頭髄外性形質細胞腫に対して放射線治療を施行した。その数ヵ月後に左鎖骨上窩リンパ節に再発病変を認め、同部に放射線治療を施行した。その後再発は認めず、無治療で経過観察していた。尿閉症状で受診し、PSAが高値であった。前立腺生検を施行し、病理診断で形質細胞腫を伴う前立腺癌と診断した。経直腸超音波検査では、前立腺体積は60mlと腫大していた。骨盤部単純MRIでは、前立腺背側に境界明瞭で拡散強調像で高信号を呈する腫瘤を認めた。PET/CTでは、前立腺が全体に腫大し、やや不均一な集積を認めた。前立腺針生検を施行し、HE染色では櫛状構造をとる異型腺管を認め、左側3本中2本で検出した。前立腺背側の腫瘤部分の生検はHE染色では核小体の出現した類円形核異形成細胞が増殖していた。CD138、λ鎖、κ鎖は陽性であった。前立腺癌及び髄外性形質細胞腫と診断し、CAB療法+放射線外照射を選択した。治療半年後のPET-CTでは前立腺は全体に縮小し、FDGの集積も低下した。治療9ヵ月後の血清PSA値も検出感度以下に低下し、現時点では髄外性形質細胞腫、前立腺癌ともに再発無く経過している。

This multi-institutional retrospective analysis examined learning curves for dosimetric parameters and operation time after introduction of intraoperatively built custom-linked (IBCL) seeds. Data from consecutive patients treated with seed implantation before and after introduction of IBCL seeds (loose seed, n = 428; IBCL seed, n = 426) were collected from 13 centers. Dose-volume histogram parameters, operation times, and seed migration rates were compared before and after introduction of IBCL seeds. At the 1-month CT analysis, no significant differences were seen in dose to 90% of prostate volume between before and after IBCL seed introduction. No learning curve for dosimetry was seen. Prostate and rectal volume receiving at least 150% of prescription dose (V150 and RV150) were higher in the loose-seed group than in the IBCL-seed group. Operation time was extended by up to 10 min when IBCL seeds were used, although there was a short learning curve of about five patients. The percentage of patients with seed migration in the IBCL-seed group was one-tenth that in the loose-seed group. Our study revealed no dosimetric demerits, no learning curve for dosimetry, and a slightly extended operation time for IBCL seeds. A significant reduction in the rate of seed migration was identified in the IBCL-seed group.

当院で密封小線源永久挿入治療を施行した前立腺癌患者51例を対象に、リンクシード治療群23例と従来の非連結シード治療群28例に分け、比較検討した。その結果、尿路への脱落線源数や肺への迷入線源数は両群間で有意差を認めなかったが、リンクシード群のほうが少ない傾向にあった。治療時間はリンクシード群の方が有意に長かったが、症例を重ねるごとに減少する傾向がみられた。前立腺線量はV150のみ非連結シード群が有意に高かったが、D90、V100では有意差を認めず、非連結シード群と比較してほぼ同等の線量分布が得られた。直腸線量は両群間で有意差がなかった。尿道線量はリンクシード群の方が有意に低値であったが、頻尿、排尿困難感、排尿時痛、尿閉などの尿路系の急性期障害に有意差はなかった。直腸出血の発症率にも有意差はなく、過去の文献と矛盾のない結果が得られた。

BACKGROUND: Radiation pneumonitis (RP) and organizing pneumonia (OP) are the two main types of lung damage that can occur after lung irradiation. The goal of this study was to evaluate the relationship between RP and OP after irradiation for breast cancer. METHODS: Four hundred and twenty-eight patients who underwent radiotherapy for breast cancer were identified. The whole breast was irradiated with two tangential photon beams. Chest computed tomography (CT) scan were performed when patients showed any symptoms that were suspicious for pneumonitis. RESULTS: Five patients (1.2%) were diagnosed with OP. All five patients showed ground glass opacities and consolidation of the border of the lesion of RP in the radiation fields. Infiltration of OP spread from the site of RP to the hilum of the ipsilateral lung. Between RP and OP, a free region space (FRS) could be detected. CONCLUSIONS: OP is closely related to RP. All OP lesions developed near the site of RP.

OBJECTIVE: The transition of microglia from the normal resting state to the activated state is associated with an increased expression of peripheral benzodiazepine receptors (PBR). The extent of PBR expression is dependent on the level of microglial activation. A PBR ligand, [(11)C]PK11195, has been used for imaging of the activation of microglia in vivo. We evaluated whether [(11)C]PK11195 PET can indicate differences of microglial activation between no treatment and lipopolysaccharide (LPS) treatment in a rat artificial injury model of brain inflammation. METHODS: On day 1, a small aliquot of absolute ethanol was injected into the rat right striatum (ST) to produce artificial brain injury. On day 3, MRI scans were performed to evaluate and select rats showing a similar degree of brain injury. Then LPS or vehicle was administered intraperitoneally. On day 4, PET scans were performed after a bolus injection of [(11)C]PK11195. Eleven rats (7 LPS administered rats, 4 LPS non-administered rats) were evaluated. We used uptake ratios of the integral of right and left striatum from 0 to 60 min as an estimate of PBR distribution volume (V (60)). The number of activated microglia and mRNA expression of inflammatory cytokines (TNFalpha, IL-1beta) were assessed by isolectin-B4 staining and RT-PCR, respectively. RESULTS: Right/left ST V (60) ratios of LPS group were significantly higher than those of non-LPS group (P < 0.03). Although there were no significant differences in the number of activated microglia between the two groups, LPS group showed higher expression of inflammatory cytokines (TNFalpha, IL-1beta) than the non-treated group indicating that further activation was induced by LPS treatment. CONCLUSION: The results suggest that intensity of PBR signals in [(11)C]PK11195 PET may be related to the level of microglial activation rather than the number in activated microglia at least in an artificial brain injury model.

OBJECTIVE: To investigate whether [(11)C]PK-11195, a specific peripheral benzodiazepine receptors (PBRs) ligand for positron emission tomography (PET), can show activated microglia in a rat brain injury model. METHODS: On day 1, ethanol was injected into the rat's right striatum (ST) using a stereotaxic operative procedure. On day 3, head magnetic resonance imaging (MRI) scans for surgically treated rats were performed to evaluate ethanol injury morphologically. On day 4, dynamic PET scans (17 injured rats and 7 non-injured controls) were performed for 60 min with an animal PET scanner under chloral hydrate anesthesia following a bolus injection of [(11)C]PK-11195 through tail vein. Because PBRs are present throughout the brain, there is no suitable receptor-free reference region. The reference tissue model may not be applicable because of low target to background ratio for low affinity of [(11)C]PK-11195 to PBRs. We evaluated the PBRs binding with regions of interest (ROIs)-based approach to estimate total distribution volume (V). We used an integral from 0 min to 60 min (V (60)) as an estimate of V. On the coronal PET image, ROIs were placed on bilateral ST. Differences in right/left ST V (60) ratios between lesioned and unlesioned control rats were compared using unpaired t tests. Immunohistochemical staining was performed for confirming the presence of activated microglia following decapitation on the PET experiment day. RESULTS: The right/left ST V (60) ratios in lesioned rats (1.07 +/- 0.08) were significantly higher than those in unlesioned control rats (1.00 +/- 0.06, P < 0.05). On immunohistochemical staining, activated microglia were exclusively observed in the injured right ST but not in the noninjured left ST of the injury rats and the bilateral ST of the non-injured control rats. CONCLUSIONS: These results suggest that [(11)C]PK-11195 PET imaging would be a useful tool for evaluating microglial activation in a rat brain injury model.

Objective To investigate whether [(11)C]PK-11195, a specific peripheral benzodiazepine receptors (PBRs) ligand for positron emission tomography (PET), can show activated microglia in a rat brain injury model. Methods On day 1, ethanol was injected into the rat&apos;s right striatum (ST) using a stereotaxic operative procedure. On day 3, head magnetic resonance imaging (MRI) scans for surgically treated rats were performed to evaluate ethanol injury morphologically. On day 4, dynamic PET scans (17 injured rats and 7 non-injured controls) were performed for 60 min with an animal PET scanner under chloral hydrate anesthesia following a bolus injection of [(11)C]PK-11195 through tail vein. Because PBRs are present throughout the brain, there is no suitable receptor-free reference region. The reference tissue model may not be applicable because of low target to background ratio for low affinity of [(11)C]PK-11195 to PBRs. We evaluated the PBRs binding with regions of interest (ROIs)-based approach to estimate total distribution volume (V). We used an integral from 0 min to 60 min (V (60)) as an estimate of V. On the coronal PET image, ROIs were placed on bilateral ST. Differences in right/left ST V (60) ratios between lesioned and unlesioned control rats were compared using unpaired t tests. Immunohistochemical staining was performed for confirming the presence of activated microglia following decapitation on the PET experiment day. Results The right/left ST V (60) ratios in lesioned rats (1.07 +/- 0.08) were significantly higher than those in unlesioned control rats (1.00 +/- 0.06, P &lt; 0.05). On immunohistochemical staining, activated microglia were exclusively observed in the injured right ST but not in the noninjured left ST of the injury rats and the bilateral ST of the non-injured control rats. Conclusions These results suggest that [(11)C]PK-11195 PET imaging would be a useful tool for evaluating microglial activation in a rat brain injury model.

Background and aims: Microglia plays an active part in brain injury and degeneration. The transition of microglia from the normal resting state to the activated state is associated with an increased expression of peripheral benzodiazepine receptors (PBRs). Increased PBRs may be used as a marker for detecting activated microglia in vivo. PET imaging of microglial activation using [C-11]-PK11195(PK), a PBRs ligand, has been investigated in several neurological conditions. Based on our basic mice experiments,a new PBR ligand, [C-11]-CB148(CB), has higher affinity than does PK. We investigated if CB PET can show activated microglia in a rat brain injury model. Methods: On day 1, under pentobarbital anesthesia, 8 μl ethanol was injected into the rat right striatum through Hamilton syringe using a steotaxic operative procedure. On day 3, MRI scans were performed to evaluate brain morphologically. On day 4, dynamic PET scans were performed for 64 min with an animal PET scanner (SHR-2000 animal PET scanner, Hamamatsu Photonics) under chloral hydrate anesthesia after a bolus injection of 39-64 MBq of CB through tail vein. Nine ethanol-injured rats and 7 non-injured control rats were evaluated. To avoid arterial sampling, we evaluated the PBRs binding with a method to estimate normalized PBRs distribution volume (V*) with 'reference' tissue containing PBRs by Ichise (Neroimage2004 22 supple2:T149-50). V* was defined as the distribution volume (V) normalized by the 'reference' region tracer delivery (K1′). V*= V/ K1′= R1/ k2 and R1= K1/ K1′ were estimated voxel-wise with two tissue parameter multilinear reference tissue model by Ichise(JCBFM2003 23:1096-112). On the coronal PET image, regions of interest (ROI) were placed on bilateral striatum (ST) guided by a rat stereotaxic atlas and Harderian glands ('reference' region). The animals were euthanized after the PET scanning and immunohistochemical staining was performed for confirmation of the presence of activated microglia. Densities of activated microglia in each rat striatum were measured. Results: The PBRs V* values (min) in injured right ST were significantly higher by 12% than in non-injured left ST (14.82±3.63vs.12.67±6.24, p&lt 0.05). Similarly, the PBR V* right/left striatum ratios were significantly higher by 11% than in control rats (1.1±1.3 vs.1.0±0.1, p&lt 0.05).On immunohistochemical staining, IB4-lection positive cells showing activated microglia were shown around the ethanol injected tract in the right striatum but not in the non-injured left striatum. V* values (min) correlated highly with densities of activated microglia (y=0.0019x ? 0.263, R2=0.79, P=0.0002). Conclusion: These Results: suggest that CB PET imaging and V* analysis would be a useful tool to evaluate microglial activation(brain inflammation) in rat brain.

マルチスライスCTは急速に普及し、現在64列の検出器を装備したものが最新モデルとしてリリースされている。マルチスライスCTの多列化が進むにつれ、検査時間の短縮、撮影範囲の拡大、体軸方向の分解能の向上が得られている。64列マルチスライスCTでは、常に0.5mmの薄いスライス厚で撮影することができるため、高い空間分解能のボリュームデータを得ることができる。また、高速三次元再構成ワークステーションの普及により、もはや三次元画像は特別なものではなくなった。64列マルチスライスCTでは、単に高速撮影ができるだけでなく、体軸方向への長距離撮影[頭部から胸部への3D-CT angiography(3D-CTA)]、CT perfusion(CTP)との複合検査、digital subtraction 3D-CT angiography(DS 3D-CTA)、動脈優位相・静脈優位相の多時相撮影など、撮影方法や造影方法を組み合わせることによりさまざまな検査が可能となり、従来よりも検査の幅が広がってきている。本稿では、われわれの施設で行っている64列マルチスライスCT「Aquilion 64」(東芝社製)を用いた神経放射線領域における検査について、実際の症例を提示しながら解説していく。(著者抄録)