Detection of esophageal fiducial marker displacement during radiation therapy with a 2-dimensional on-board imager: analysis of internal margin for esophageal cancer

PURPOSE

To quantify the interfraction displacement of esophageal fiducial markers for primary esophageal cancer radiation therapy.

METHODS AND MATERIALS

Orthogonal 2-dimensional (2D) matching records fused to vertebrae were analyzed in clinically staged T1/2N0 esophageal cancer patients undergoing endoscopic clipping as fiducial metal markers. Displacement of the markers between the digitally reconstructed radiographs and on-board kilovoltage images during radiation therapy was analyzed according to direction and esophageal site.

RESULTS

Forty-four patients, with 81 markers (10 proximal, 42 middle, and 29 distal), underwent 367 2D matching sessions during radiation therapy. The mean (SD) absolute marker displacement was 0.26 (0.30) cm in the right-left (RL), 0.50 (0.39) cm in the superior-inferior (SI), and 0.24 (0.21) cm in the anterior-posterior (AP) direction. Displacement was significantly larger in the SI than in the RL and AP directions (P<.0001). In the SI direction, mean absolute displacements of the distal, middle, and proximal esophagus were 0.67 (0.45) cm, 0.42 (0.32) cm, and 0.36 (0.30) cm, respectively. Distal esophagus displacement was significantly larger than those of the middle and proximal esophagus (P<.0001). The estimated internal margin to cover 95% of the cases was 0.75 cm in the RL and AP directions. In the SI direction, the margin was 1.25 cm for the proximal and middle esophagus and 1.75 cm for the distal esophagus.

CONCLUSIONS

The magnitude of interfraction displacement of esophageal clips was larger in the SI direction, particularly in the distal esophagus, but substantial displacement was observed in other directions and at other esophageal sites. It is practical to take estimated movements into account with internal margins, even if vertebrae-based 2D matching is performed.

Predicting pubic arch interference in prostate brachytherapy on transrectal ultrasonography-computed tomography fusion images

We investigated the usefulness of the fusion image created by transrectal ultrasonography (TRUS) and large-bore computed tomography (CT) for predicting pubic arch interference (PAI) during prostate seed brachytherapy. The TRUS volume study was performed in 21 patients, followed by large-bore computed tomography of patients in the lithotomy position. Then, we created TRUS-CT fusion images using a radiation planning treatment system. TRUS images in which the prostate outline was the largest were overlaid on CT images with the narrowest pubic arch. PAI was estimated in the right and left arch separately and classified to three grades: no PAI, PAI positive within 5 mm and PAI of >5 mm. If the estimated PAI was more than 5 mm on at least one side of the arch, we judged there to be a significant PAI. Brachytherapy was performed in 18 patients who were evaluated as not having significant PAI on TRUS. Intra-operative PAI was observed in one case, which was also detected with a fusion image. On the other hand, intra-operative PAI was not observed in one case that had been evaluated as having significant PAI with a fusion image. In the remaining three patients, TRUS suggested the presence of significant PAI, which was also confirmed by a fusion image. Intra-operative PAI could be predicted by TRUS-CT fusion imaging, even when it was undetectable by TRUS. Although improvement of the reproducibility of the patients' position to avoid false-positive cases is warranted, TRUS-CT fusion imaging has the possibility that the uncertainty of TRUS can be supplemented.

[Statistical analysis of 32 patients with nasopharyngeal carcinoma]

In order to assess the clinical outcome and prognostic factors of patients with nasopharyngeal carcinoma (NPC) who were initially treated in the Department of Otorhinolaryngology, Head and Neck Surgery, Keio University School of Medicine between 1997 and 2006, statistical analyses were performed based on the patient medical records. Cause-specific survival (CSS) and disease-free survival (DFS) in all cases (stage I to IV, n = 32) and advanced cases (stage III and IV, n = 22) were estimated using the Kaplan-Meier method. The independent prognostic values of the clinical and therapeutic factors were determined using multivariate Cox proportional hazards models.

RESULTS

The 5-year CSS/DFS were 43.4%/34.8% in all cases and 34.5%/29.8% in advanced cases. Multivariate analysis revealed that, in all cases, the independent prognostic factors for CSS were age (> or = 61 vs. < or = 60, risk ratio (RR) = 5.717, p = 0.006), T-stage (3/4 vs. 1/2, RR = 6.957, p = 0.004), and the use of platinum agents (unused vs. used, RR = 3.911, p = 0.012), whereas those for DFS were T-stage (3/4 vs. 1/2, RR = 3.499, p = 0.019) and the use of platinum agents (unused vs. used, RR = 2.947, p = 0.028). In advanced cases, the use of platinum agents alone was significant for both CSS (RR = 4.503, p = 0.023) and DFS (RR = 4.218, p = 0.014). The patients who received neoadjuvant chemotherapy (NAC) showed better CSS and DFS than the patients who did not (p = 0.066 and p = 0.025, respectively) in a univariate analysis (Log-rank test), although no significant difference was seen between these groups in the multivariate analysis.

CONCLUSION

The advantage of the administration of platinum agents in the treatment of NPC was statistically corroborated even in our study with its small sample size. As agents combined with chemoradiotherapy, the efficacy of docetaxel alone did not seem comparable to that of platinum agents. The docetaxel-CDDP-5-FU regimen applied as NAC was suggested to be possibly beneficial for advanced cases of NPC.

Enhancement of radiosensitivity by a unique novel NF-κB inhibitor, DHMEQ, in prostate cancer

Background:

Inducible activation of nuclear factor (NF)-κB is one of the principal mechanisms through which resistant prostate cancer cells are protected from radiotherapy. We hypothesised that inactivation of inducible NF-κB with a novel NF-κB inhibitor, DHMEQ, would increase the therapeutic effects of radiotherapy.

Methods:

PC-3 and LNCaP cells were exposed to irradiation and/or DHMEQ. Cell viability, cell cycle analysis, western blotting assay, and NF-κB activity were measured. The antitumour effect of irradiation combined with DHMEQ in vivo was also assessed.

Results:

The combination of DHMEQ with irradiation resulted in cell growth inhibition and G2/M arrest relative to treatment with irradiation alone. Inducible NF-κB activity by irradiation was inhibited by DHMEQ treatment. The expression of p53 and p21 in LNCaP, and of 14-3-3σ in PC-3 cells, was increased in the combination treatment. In the in vivo study, 64 days after the start of treatment, tumour size was 85.1%, 77.1%, and 64.7% smaller in the combination treatment group than that of the untreated control, DHMEQ-treated alone, and irradiation alone groups, respectively.

Conclusion:

Blockade of NF-κB activity induced by radiation with DHMEQ could overcome radio-resistant responses and may become a new therapeutic modality for treating prostate cancer.

Anti-Tumor Effects of Water-Soluble Propolis on a Mouse Sarcoma Cell Line In Vivo and In Vitro

The honeybee product propolis and its extracts are known to have biological effects such as antibiotic, anti-viral, anti-inflammatory and anti-tumor activities. This study was designed to investigate whether water-soluble propolis (WSP) inhibits tumor growth. The tumor cell line used was mouse sarcoma 180 (S-180), and its growth was determined in vitro and in vivo with exposure to different concentrations of WSP.

The effects of WSP on tumor cells in vitro were evaluated by measuring the intracellular uptake of 3 H -thymidine. 3 H -thymidine uptake was inhibited in accordance with the concentration of WSP. The minimum concentration of WSP necessary for 3 H -thymidine uptake inhibition was 1.0 μg/ml and uptake was suppressed to 88% of the level in non-treated cells at this concentration.

In an experiment using tumor-bearing mice, oral administration of WSP was begun 24 hours after transplantation of S-180 cells. WSP was administered to the mice 5 times, every other day for 10 days. The doses were 320 mg/kg (10 mg/mouse) or 960 mg/kg (30 mg/mouse) of body weight. All mice were sacrificed 10 days after transplantation, and tumor growth was evaluated. The orally administered WSP significantly inhibited the growth of transplanted tumors ( p < 0.05). Furthermore, histological findings revealed a significant reduction in mitotic cells and tumor invasion of the muscular tissue at both dose-levels of WSP.

Safety and efficacy of total body irradiation, cyclophosphamide, and cytarabine as a conditioning regimen for allogeneic hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia

Disease relapse still greatly interferes with the success of allogeneic hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia (ALL). This study retrospectively evaluated the long-term safety and efficacy of a conditioning regimen consisting of total body irradiation (TBI; 12 Gy), cyclophosphamide (CY; 60 mg kg(-1) , two doses), and high-dose cytarabine (Ara-C; 2 g m(-2) ; four doses) for patients with ALL. Fifty-five patients (median age: 31-years old) were evaluated. Stem cells were from human leukocyte antigen-identical siblings in 22 patients and from alternative donors in 33. There were no cases of early death before engraftment, and 100-day transplant-related mortality was 7.3%. With a median follow-up period of 9.6 years, 5-year overall and disease-free survival were 63.2% (95% CI: 46.5-79.9%) and 63.6% (95% CI: 47.1-80.1%) in patients with complete remission, respectively, both of which were significantly higher than the values of 27.3% (95% CI: 8.7-46.0%) and 22.7% (95% CI: 5.3-40.1%) for patients in advanced stages (P < 0.01). These results suggest that TBI and CY (TBI-CY) plus Ara-C could be a feasible and effective conditioning regimen for adult patients with ALL both in remission and in advanced stages, and a future study to compare this combination therapy with TBI-CY is required.

[Allogeneic hematopoietic stem cell transplantation with fludarabine, melphalan, and total body irradiation as a conditioning for elderly patients with myeloid malignancies]

A variety of reduced-intensity conditionings have been used in the reported studies of allogeneic hematopoietic stem cell transplantation (HSCT) for elderly patients with myeloid hematological malignancies. This study retrospectively analyzed the outcome of allogeneic HSCT for 10 patients aged 50 years or older with myeloid hematological malignancies after conditioning with fludarabine (125 mg/m(2)), melphalan (140 mg/m(2)) and total body irradiation (TBI; 8 Gy). Median age of the patients was 56.5 years, and diagnoses included acute myelogenous leukemia, advance myelodysplastic syndrome, and secondary myelofibrosis. Sources of stem cells were bone marrow from sibling (n=4) or unrelated donor (n=6). Both overall and disease-free survival rates were 40.0% (95% CI: 10.6~69.4%). Causes of death were relapse (n=2), fungal infection (n=2), and secondary malignancies (n=2). Because of a high incidence of transplant-related mortality, further refinement of this conditioning is required.

Comparison of clinical, tumour-related and dosimetric factors in grade 0-1, grade 2 and grade 3 radiation pneumonitis after stereotactic body radiotherapy for lung tumours

OBJECTIVE

The aim of this study was to investigate significant clinical, tumour-related and dosimetric factors among patients with grade 0-1, grade 2 and grade 3 radiation pneumonitis (RP) after stereotactic body radiotherapy (SBRT) for lung tumours.

METHODS

Patients (n=128) with a total of 133 lung tumours treated with SBRT of 50 Gy in 5 fractions were analysed. RP was graded according to the Common Terminology Criteria for Adverse Events v.3.0. Significant factors were identified by univariate and multivariate analyses. Threshold dose-volume histograms (DVHs) were constructed to identify the incidence of RP.

RESULTS

The median follow-up period was 12 months (range, 6-45 months). In univariate analyses, gender, operability, forced expiratory volume in 1 s (FEV1), internal target volume, lung volumes treated with doses >5-30 Gy (V5-30) and mean lung dose were significant factors differentiating between grade 0-1 and grade 2 RP, and V15-30 were significant factors differentiating between grade 2 and grade 3. However, no factors were significant between grade 0-1 and grade 3 RP. Multivariate analysis showed that female gender, high FEV1 and high V15 were significant factors differentiating between grade 0-1 and grade 2 RP. Threshold DVH curves were created based on ≤5% and ≤15% risk of grade 2 RP among patients with grade 0-2 RP.

CONCLUSIONS

Grade 0-2 RP was dose-volume dependent, and female gender and high FEV1 were significant predictive clinical factors for grade 2 RP among patients with grade 0-2 RP. However, incidences of V15-30 in grade 3 RP were significantly lower than those in grade 2 RP, and no significant clinical or tumour-related factors were found. Further studies are needed to identify the mechanism underlying the development of grade 3 RP after SBRT for lung tumours.

Pericardial and pleural effusions after definitive radiotherapy for esophageal cancer

PURPOSE

We investigated the incidences of pericardial and pleural effusions after definitive radiotherapy with or without concurrent chemotherapy were analyzed retrospectively.

METHODS

One hundred and forty-seven patients with esophageal cancer received definitive radiotherapy or concurrent chemoradiotherapy (CCR). Follow-up chest Computed Tomography scans were reviewed to detect pericardial and pleural effusions. Adverse events were graded according to the Radiation Therapy Oncology Group Common Toxicity Criteria.

RESULTS

The median follow-up was 34 (range, 6 to 84) months. Numbers of eligible patients evaluated for pericardial and pleural effusions were 107 and 101, respectively. Pericardial effusions exceeding grade 1 and grade 2 toxicities were observed in 46 (43%) and 15 (14%) patients, respectively. The corresponding numbers for pleural effusions were 44 (44%) and 18 (18%). Onset of effusion ranged from 1 to 65 months after treatment. Multivariate analysis identified radiation field width of the mediastinum exceeding 8 cm as a significant risk factor for both pericardial and pleural effusions. Age and field length exceeding 20 cm were identified as independent risk factors for pleural effusion.

CONCLUSIONS

Pericardial and pleural effusions after radiotherapy or CCR are occasionally recognized as adverse events in patients with esophageal cancer. The mediastinal radiation field width can be a simple indicator for predicting those adverse events.

Prostate brachytherapy seed migration to a left varicocele

PURPOSE

To report a rare case of seed migration to a left varicocele after transperineal interstitial prostate brachytherapy with loose iodine-125 ((125)I) seeds.

METHODS AND MATERIALS

A 73-year-old man presented with a serum prostate-specific antigen level of 5.21 ng/mL, Gleason score of 7 (3+4), and clinical T1c adenocarcinoma of the prostate. The patient underwent transperineal interstitial prostate brachytherapy with loose (125)I seeds followed by external beam radiation therapy. Two weeks after seed implantation, a followup pelvic radiograph was obtained. One month after seed implantation, a pelvic computed tomography scan for postimplant dosimetric analysis was carried out. Subsequent ultrasound examination of the scrotum was undertaken.

RESULTS

Two weeks after seed implantation, an anteroposterior pelvic radiograph showed that a migrated seed was overlapped by the scrotum. Postimplant pelvic computed tomography revealed that a seed had migrated to the left side of the scrotum. Subsequent ultrasound examination of the scrotum revealed that the patient had a left varicocele to which the seed had migrated. The patient had no symptoms related to the migrated seed.

CONCLUSIONS

This is the first report of seed migration to a left varicocele after transperineal interstitial prostate brachytherapy with loose (125)I seeds. For the present case, we suggest that the seed moved from the prostate to the left varicocele through the pelvic veins, bypassing the systemic circulation.

Incidence of seed migration to the chest, abdomen, and pelvis after transperineal interstitial prostate brachytherapy with loose (125)I seeds

Background

The aim was to determine the incidence of seed migration not only to the chest, but also to the abdomen and pelvis after transperineal interstitial prostate brachytherapy with loose ¹²⁵I seeds.

Methods

We reviewed the records of 267 patients who underwent prostate brachytherapy with loose ¹²⁵I seeds. After seed implantation, orthogonal chest radiographs, an abdominal radiograph, and a pelvic radiograph were undertaken routinely to document the occurrence and sites of seed migration. The incidence of seed migration to the chest, abdomen, and pelvis was calculated. All patients who had seed migration to the abdomen and pelvis subsequently underwent a computed tomography scan to identify the exact location of the migrated seeds. Postimplant dosimetric analysis was undertaken, and dosimetric results were compared between patients with and without seed migration.

Results

A total of 19,236 seeds were implanted in 267 patients. Overall, 91 of 19,236 (0.47%) seeds migrated in 66 of 267 (24.7%) patients. Sixty-nine (0.36%) seeds migrated to the chest in 54 (20.2%) patients. Seven (0.036%) seeds migrated to the abdomen in six (2.2%) patients. Fifteen (0.078%) seeds migrated to the pelvis in 15 (5.6%) patients. Seed migration occurred predominantly within two weeks after seed implantation. None of the 66 patients had symptoms related to the migrated seeds. Postimplant prostate D90 was not significantly different between patients with and without seed migration.

Conclusion

We showed the incidence of seed migration to the chest, abdomen and pelvis. Seed migration did not have a significant effect on postimplant prostate D90.

Phase I study of neoadjuvant chemoradiotherapy consisting of S-1 and cisplatin for patients with resectable advanced gastric cancer (KOGC-01)

BACKGROUND

The prognosis for advanced gastric cancer is poor, with surgery as the only treatment for resectable advanced gastric cancer. Therefore, treatment options that might improve the prognosis are needed. To that end, neoadjuvant chemoradiotherapy with S-1 and cisplatin (CDDP) was investigated.

PATIENTS AND METHODS

The chemotherapy schedule included one cycle repeated after 6 weeks. S-1 was administered orally every day on days 1-21 and CDDP was infused on days 1, 8 and 15. Radiation therapy was started concurrently with chemotherapy and repeated daily on days 1-5, 8-12, 15-19, and 22-26.

RESULTS

A total of 10 patients were recruited. The first four patients were entered into level 1 (CDDP, 20 mg/m²). The next six patients were entered into level 0 (15 mg/m²), because of dose-limiting toxicity (delaying the second course of chemotherapy in two patients) that had been observed at level 1. The maximum tolerated dose (MTD) of CDDP was 20 mg/m². Seven patients underwent surgery and all had an R0 (no residual tumor) resection without surgical complications.

CONCLUSION

Neoadjuvant chemoradiotherapy with S-1 and CDDP may cause surgery to be delayed, but shows promise for resectable advanced gastric cancer.

Prevention of cytarabine-induced kerato-conjunctivitis by eye rinse in patients receiving high-dose cytarabine and total body irradiation as a conditioning for hematopoietic stem cell transplantation

We previously reported a high incidence of kerato-conjunctivitis in patients receiving high-dose cytarabine following total body irradiation (TBI) as a conditioning for hematopoietic stem cell transplantation (HSCT) even on prophylaxis with topical corticosteroid. This study aimed to evaluate whether addition of eye rinse, which was designed to remove cytarabine from ocular surface, further reduces the incidence of kerato-conjunctivitis in the same setting. Seventy-six patients receiving cytarabine at a dose of 3 g/m(2) every 12 h for 4 days after receiving TBI (12 Gy) as conditioning for HSCT were evaluated. All patients received betamethasone sodium phosphate eye drops. Twenty-three patients were further instructed to rinse their eyes with sterile saline every 10-15 min during and for two additional hours after the completion of each cytarabine infusion. Among 23 patients with eye rinse, Grades 2-3 and 1-3 kerato-conjunctivitis were observed in 4 (17.4%) and 5 patients (21.7%), respectively. These incidences were significantly lower than those [35 (66.0%) and 41 (77.4%)] observed in 53 patients without eye rinse (P < 0.001 and P < 0.00001, respectively). These results strongly suggest that eye rinse effectively reduces the incidence and severity of cytarabine-induced kerato-conjunctivitis in HSCT recipients who receive high-dose cytarabine following TBI.

Radiation-sensitizing effect of low-concentration docetaxel on human esophageal squamous cell carcinoma cell lines

Esophageal squamous cell carcinoma (ESCC) is more sensitive to radiation and chemotherapy than other cancers of the digestive system, and combined modality therapy may represent a promising treatment method. The radiation-sensitizing effect of docetaxel on ESCC cell lines was investigated. A colony formation assay was performed in which ESCC cell lines (TE2, TE3) and A431 were exposed to docetaxel (from 1.0×10(-11) to 10(-7) M) for 3 h to determine the concentration of docetaxel that was not able to kill individual cells (i.e., the non-cytocidal concentration). Individual cell lines were then exposed to the non-cytocidal concentration of docetaxel prior to, during, and after irradiation to determine whether the timing of docetaxel administration affected cell survival. In addition, flow-cytometry was performed, and the cell cycle was examined prior to and after docetaxel exposure to assess the mechanism of docetaxel as a radiation sensitizer. Docetaxel exhibited a concentration-dependent cytocidal effect, with a different IC(50) for each cell type. Almost no cytocidal effect was observed at the following docetaxel concentrations: A431, ≤1.0×10(-10) M; TE-2 and TE-3, ≤1.0×10(-9) M. Concurrent treatment with docetaxel and radiation tended to decrease cell survival in all the cell lines compared with docetaxel or radiation alone. Cell survival was lowest when the cells were treated using X-ray irradiation after docetaxel exposure (p<0.05). Flow cytometry revealed that in all three cell lines, docetaxel exposure increased the G2/M cell fraction with a higher increase in the cell line that exhibited the highest radiosensitivity. This study demonstrated that the administration of docetaxel at a non-cytocidal concentration prior to radiotherapy produced a synergistic cell-killing effect in SCC cell lines.

CT evaluations of focal liver reactions following stereotactic body radiotherapy for small hepatocellular carcinoma with cirrhosis: relationship between imaging appearance and baseline liver function

This study aimed to assess the imaging appearances of focal liver reactions following stereotactic body radiotherapy (SBRT) for small hepatocellular carcinoma (HCC) and to examine relationships between imaging appearance and baseline liver function. We retrospectively studied 50 lesions in 47 patients treated with SBRT (30-40 Gy in 5 fractions) for HCC, who were followed up for more than 6 months. After SBRT, all patients underwent regular follow-ups with blood tests and dynamic CT scans. At a median follow-up of 18.1 months (range 6.2-43.7 months), all lesions but one were controlled. 3 density patterns describing focal normal liver reactions around HCC tumours were identified in pre-contrast, arterial and portal-venous phase scans: iso/iso/iso in 4 patients (Type A), low/iso/iso in 8 patients (Type B) and low/iso (or high)/high in 38 patients (Type C). Imaging changes in the normal liver surrounding the treated HCC began at a median of 3 months after SBRT, peaked at a median of 6 months and disappeared 9 months later. Liver function, as assessed by the Child-Pugh classification, was the only factor that differed significantly between reactions to treatment showing "non-enhanced" (Type A and B) and "enhanced" (Type C) appearances in CT. Hence, liver tissue with preserved function is more likely to be well enhanced in the delayed phase of a dynamic contrast-enhanced CT scan. The CT appearances of normal liver seen in reaction to the treatment of an HCC by SBRT were therefore related to background liver function and should not be misread as recurrence of HCC.

Preimplant factors affecting postimplant CT-determined prostate volume and the CT/TRUS volume ratio after transperineal interstitial prostate brachytherapy with 125I free seeds

Background

The aim was to identify preimplant factors affecting postimplant prostate volume and the increase in prostate volume after transperineal interstitial prostate brachytherapy with ¹²⁵I free seeds.

Methods

We reviewed the records of 180 patients who underwent prostate brachytherapy with ¹²⁵I free seeds for clinical T1/T2 prostate cancer. Eighty-one (45%) of the 180 patients underwent neoadjuvant hormonal therapy. No patient received supplemental external beam radiotherapy. Postimplant computed tomography was undertaken, and postimplant dosimetric analysis was performed. Univariate and multivariate analyses were performed to identify preimplant factors affecting postimplant prostate volume by computed tomography and the increase in prostate volume after implantation.

Results

Preimplant prostate volume by transrectal ultrasound, serum prostate-specific antigen, number of needles, and number of seeds implanted were significantly correlated with postimplant prostate volume by computed tomography. The increase in prostate volume after implantation was significantly higher in patients with neoadjuvant hormonal therapy than in those without. Preimplant prostate volume by transrectal ultrasound, number of needles, and number of seeds implanted were significantly correlated with the increase in prostate volume after implantation. Stepwise multiple linear regression analysis showed that preimplant prostate volume by transrectal ultrasound and neoadjuvant hormonal therapy were significant independent factors affecting both postimplant prostate volume by computed tomography and the increase in prostate volume after implantation.

Conclusions

The results of the present study show that preimplant prostate volume by transrectal ultrasound and neoadjuvant hormonal therapy are significant preimplant factors affecting both postimplant prostate volume by computed tomography and the increase in prostate volume after implantation.