Comparing different boost concepts and beam configurations for proton therapy of pancreatic cancer

Background and Purpose

Interfractional geometrical and anatomical variations impact the accuracy of proton therapy for pancreatic cancer. This study investigated field-in-field (FIF) and simultaneous integrated boost (SIB) concepts for scanned proton therapy treatment with different beam configurations.

Materials and Methods

Robustly optimized treatment plans for fifteen patients were generated using FIF and SIB techniques with two, three, and four beams. The prescribed dose in 20 fractions was 60 Gy(RBE) for the internal gross tumor volume (IGTV) and 46 Gy(RBE) for the internal clinical target volume. Verification computed tomography (vCT) scans was performed on treatment days 1, 7, and 16. Initial treatment plans were recalculated on the rigidly registered vCTs. V100% and D95% for targets and D2cm3 for the stomach and duodenum were evaluated. Robustness evaluations (range uncertainty of 3.5 %) were performed to evaluate the stomach and duodenum dose-volume parameters.

Results

For all techniques, IGTV V100% and D95% decreased significantly when recalculating the dose on vCTs (p < 0.001). The median IGTV V100% and D95% over all vCTs ranged from 74.2 % to 90.2 % and 58.8 Gy(RBE) to 59.4 Gy(RBE), respectively. The FIF with two and three beams, and SIB with two beams maintained the highest IGTV V100% and D95%. In robustness evaluations, the ΔD2cm3 of stomach was highest in two beams plans, while the ΔD2cm3 of duodenum was highest in four beams plans, for both concepts.

Conclusion

Target coverage decreased when recalculating on CTs at different time for both concepts. The FIF with three beams maintained the highest IGTV coverage while sparing normal organs the most.

Clinical Outcomes of Intraoperative Radiotherapy, Postoperative Radiotherapy, and Definitive Radiotherapy for Non-metastatic Pancreatic Cancer

OBJECTIVE

The aim of this study is to evaluate the utility of adjuvant radiotherapy (intraoperative radiotherapy, IORT; postoperative radiotherapy, PORT), and definitive radiotherapy for non-metastatic pancreatic cancer.

METHODS

Ninety-nine patients were analyzed. Thirty patients underwent IORT with surgery, 31 underwent PORT after surgery, and 38 underwent definitive radiotherapy. Tumor stage [Union for International Cancer Control (UICC) 2009] was as follows: Stage I, 7; IIA, 16; IIB, 31; III, 45. The doses for IORT, PORT, and definitive radio therapy were 20 to 30, 40 to 64.6, and 50.4 to 61.2 Gy, respectively. Associations between clinical parameters including age, gender, tumor site, stage, performance status, surgical margin, and use of chemotherapy and local control (LC) or overall survival (OS) were analyzed.

RESULTS

Follow-up periods for all patients were 1.1-145 months (median, 11). OS rate in the IORT, PORT, and definitive radiotherapy groups was 22%, 16%, and 6%, respectively, at 2 years. The 5-year OS rate was 13%, 3.2%, and 0%, respectively. Local control rate at 2 years was 33%, 35%, and 0%, respectively. No Grade ≥ 3 tox icities were observed. Distant metastasis was less common in the IORT group. Stage and surgical margin were sig nificant factors for OS after IORT. Performance status and chemotherapy were significant factors for OS after PORT and definitive radiotherapy.

CONCLUSIONS

The present study showed the safety of the three treatment modalities, but the outcomes were not satisfactory. More intensive strategies including radiotherapy should be investigated.

Acute genitourinary toxicity of pencil beam scanning proton therapy for localized prostate cancer: utility of the transition zone index and average urinary flow rate in predicting acute urinary retention

BACKGROUND

The purpose of this study was to evaluate the incidence of acute genitourinary toxicities in patients undergoing pencil beam scanning proton therapy for prostate cancer and investigate predictive factors associated with acute urinary retention.

METHODS

A total of 227 patients treated between 2018 and 2021 were divided into the normo-fractionated proton therapy group (n = 107) and the moderately hypo-fractionated proton therapy group (n = 120), with prescribed doses of 76-78 Gy relative biological effectiveness in 38-39 fractions and 60-63 Gy relative biological effectiveness in 20-21 fractions, respectively. Uroflowmetry parameters and the transition zone index were prospectively evaluated.

RESULTS

Forty-five patients (42%) in the normo-fractionated proton therapy and 33 (28%) in the moderately hypo-fractionated proton therapy developed acute grade 2 genitourinary toxicities (P = 0.02). The most common acute genitourinary toxicity was acute urinary retention. Thirty-nine patients (36%) treated with normo-fractionated proton therapy and 27 (23%) treated with moderately hypo-fractionated proton therapy developed grade 2 acute urinary retention (P = 0.02). No patients developed grade ≥ 3 toxicity. Univariate analysis showed the transition zone index, prostate volume, international prostate symptom score, voided volume, maximum flow rate and average flow rate were associated with grade 2 acute urinary retention. Multivariate analysis in both groups revealed the transition zone index (P = 0.025 and 0.029) and average flow rate (P = 0.039 and 0.044) were predictors of grade 2 acute urinary retention.

CONCLUSIONS

The incidence of acute genitourinary toxicities was lower in the moderately hypo-fractionated proton therapy compared with the normo-fractionated proton therapy. Lower pretreatment average flow rate and a higher transition zone index were useful predictors of grade 2 acute urinary retention.

Comparison of intensity-modulated radiotherapy with the 5-field technique, helical tomotherapy and volumetric modulated arc therapy for localized prostate cancer

The outcomes of three methods of intensity-modulated radiation therapy (IMRT) for localized prostate cancer were evaluated. Between 2010 and 2018, 308 D'Amico intermediate- or high-risk patients were treated with 2.2 Gy daily fractions to a total dose of 74.8 Gy in combination with hormonal therapy. Overall, 165 patients were treated with 5-field IMRT using a sliding window technique, 66 were then treated with helical tomotherapy and 77 were treated with volumetric modulated arc therapy (VMAT). The median age of patients was 71 years. The median follow-up period was 75 months. Five-year overall survival (OS) and biochemical or clinical failure-free survival (FFS) rates were 95.5 and 91.6% in the 5-field IMRT group, 95.1 and 90.3% in the tomotherapy group and 93.0 and 88.6% in the VMAT group, respectively, with no significant differences among the three groups. The 5-year cumulative incidence of late grade ≥2 genitourinary and gastrointestinal toxicities were 7.3 and 6.2%, respectively, for all patients. Late grade ≥2 gastrointestinal toxicities were less frequent in patients undergoing VMAT (0%) than in patients undergoing 5-field IMRT (7.3%) and those undergoing tomotherapy (11%) (P = 0.025), and this finding appeared to be correlated with the better rectal DVH parameters in patients undergoing VMAT. Other toxicities did not differ significantly among the three groups, although bladder dose-volume parameters were slightly worse in the tomotherapy group than in the other groups. Despite differences in the IMRT delivery methods, X-ray energies and daily registration methods, all modalities may be used as IMRT for localized prostate cancer.

Dosimetric Comparison of Helical Tomotherapy and Intensity-Modulated Proton Therapy in Hippocampus- and Scalp-Sparing Whole Brain Radiotherapy

Objective: Cognitive decline and alopecia after radiotherapy are challenging problems. We aimed to compare whole brain radiotherapy (WBRT) plans reducing radiation dose to the hippocampus and scalp between helical tomotherapy (HT) and intensity-modulated proton therapy (IMPT). Methods: We conducted a planning study of WBRT for 10 patients. The clinical target volume was defined as the whole brain excluding the hippocampus avoidance (HA) region. The prescribed dose was 30 Gy in 10 fractions to cover 95% of the target. Constraint goals were defined for the target and organs at risk (OAR). Results: Both techniques met the dose constraints for the target and OAR. However, the coverage of the target (dose covering 95% [D95%] and 98% [D98%] of the volume) were better in IMPT than HT (HT vs IMPT: D95%, 29.9 Gy vs 30.0 Gy, P < .001; D98%, 26.7 Gy vs 28.1 Gy, P = .002). The homogeneity and conformity of the target were also better in IMPT than HT (HT vs IMPT: homogeneity index, 1.50 vs 1.28, P < .001; conformity index, 1.30 vs 1.14, P < .001). IMPT reduced the D100% of the hippocampus by 59% (HT vs IMPT: 9.3 Gy vs 3.8 Gy, P < .001) and reduced the Dmean of the hippocampus by 37% (HT vs IMPT: 11.1 Gy vs 7.0 Gy, P < .001) compared with HT. The scalp IMPT reduced the percentage of the volume receiving at least 20 Gy (V20Gy) and V10Gy compared with HT (HT vs IMPT: V20Gy, 56.7% vs 6.6%, P < .001; V10Gy, 90.5% vs 37.1%, P < .001). Conclusion: Both techniques provided acceptable target dose coverage. Especially, IMPT achieved excellent hippocampus- and scalp-sparing. HA-WBRT using IMPT is a promising treatment to prevent cognitive decline and alopecia.

Hyperthermia with Chemotherapy for Unresectable Gastric Cancer in a Patient with a Vagus Nerve Stimulator Implant: A Case Report

BACKGROUND Radiofrequency (RF) hyperthermia is commonly used as an adjunct to established treatment modalities such as chemotherapy and radiotherapy for the management of cancer patients. This case report aims to introduce the use of hyperthermia, in combination with chemotherapy, for the treatment of unresectable gastric cancer in a patient implanted with a vagus nerve stimulator (VNS). CASE REPORT A 55-year-old man with dermatomyositis, laryngeal squamous cell carcinoma in situ and double synchronous gastric cancer was found to have unresectable gastric disease during surgery despite neoadjuvant chemotherapy. Postoperatively, he received chemotherapy with RF hyperthermia. The patient had a VNS implant to treat epileptic seizures. VNS failure due to RF hyperthermia was an area of significant concern, and the procedures were completed with a full preparation to manage epileptic seizures in the event of its anticipated occurrence. Twenty-one thermotherapies were performed over 21 weeks. After 3 courses of S-1 chemotherapy (12 weeks) with RF hyperthermia without any adverse events, the regimen was changed to S-1+ CDDP combination chemotherapy (SP) and RF hyperthermia. The patient continued to receive treatment with a decrease in the size of the primary gastric tumors as well as lymph node metastases, without major adverse events, until he died due to disseminated disease. CONCLUSIONS We report the first case of unresectable gastric cancer with VNS implants in which chemo-hyperthermal therapy was safe and successful. This case report highlights the importance of providing a multidisciplinary treatment with appropriate measures for patients with intractable cancer who have received special treatments for underlying comorbidities.

Local radiotherapy for pleural dissemination of thymic tumors after initial treatment

Pleural dissemination is a common pattern of failure after initial treatment of thymoma and thymic carcinoma, but there is no standardized treatment. As these tumors are relatively radiosensitive, we investigated the effectiveness of radiotherapy. Twenty patients underwent 33 series of local radiotherapy for 96 pleural dissemination lesions after initial treatment. Conventional radiotherapy (CRT), tomotherapy, and combination of the two were employed in 19, 13, and 1 series, respectively. The median follow-up period after the first irradiation for pleural dissemination was 46 months (range, 14-161). For all 20 patients, overall survival (OS) rates from initial radiotherapy for pleural dissemination were 100% at three years and 86% at five years. Progression-free survival (PFS) rates after 33 series of radiotherapy were 30% at three years and 16% at five years. Local control (LC) rates for 96 lesions were 98% at three years and 96% at five years. In-field recurrence was observed in only two among the 96 lesions. One patient (5%) developed grade 3 radiation pneumonitis and another (5%) developed grade 3 pericardial effusion. No other serious adverse events were observed. When disseminated nodules can be covered within localized fields, local radiotherapy may be a treatment option. Using tomotherapy, multiple lesions can be treated safely.

Changes in pulmonary function and their correlation with dose-volume parameters in patients undergoing stereotactic body radiotherapy for lung cancer

It is desirable to estimate the degree of the decrease in pulmonary function before lung stereotactic body radiation therapy (SBRT) especially for patients with poor pulmonary function. The purpose of this study was to investigate whether decreases in pulmonary function after SBRT may be predicted from radiation dose-volume parameters. A total of 70 patients undergoing SBRT were evaluated for changes in pulmonary function. Of these, 67 had primary lung cancer and 3 had lung metastasis. Twenty-six (37%) patients had chronic obstructive pulmonary disease. Pulmonary function tests (PFTs) were performed shortly before and at 18-24 months after SBRT. Radiation pneumonitis was Grade 2 in 10 patients and Grade 3 in 1. Mean forced vital capacity (FVC) decreased from 2.67 to 2.51 L (P < 0.01) and mean forced expiratory volume in 1 s (FEV1) decreased from 1.80 to 1.72 L (P < 0.01). Planning target volume (PTV) was correlated with changes in FVC. Changes in percent predicted FVC were correlated with %V5Gy (% of lung volume receiving > 5 Gy) and %V40Gy. Although the correlation was not significant, the %V20Gy value was the closest to the percent reduction in predicted FVC; %V20Gy of 10% tended to be associated with ~10% reduction in predicted FVC. Patients with poor pulmonary function did not necessarily show greater decreases in each PFT parameter. Decreases in FVC and FEV1 were within previously reported ranges. PTV was associated with decreases in FVC. The %V20Gy value was closest to the percentage decrease in predicted FVC.

The efficacy of eribulin mesylate for patients with cutaneous angiosarcoma previously treated with taxane: a multicentre prospective observational study

BACKGROUND

Taxanes are the current first-line treatment for advanced cutaneous angiosarcoma (CAS) for patients who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. However, no effective second-line therapy for such patients has been established.

METHODS

We designed a single-arm prospective observational study of eribulin mesylate (ERB) administered at a dose of 1·4 mg m^-2 on days 1 and 8 in a 21-day cycle. Patients with advanced CAS who were previously treated with a taxane and were scheduled to begin ERB treatment were enrolled. The primary endpoint was overall survival (OS) and the secondary endpoints were response rate (RR), progression-free survival (PFS) and toxicity assessment.

RESULTS

We enrolled a total of 25 patients. The median OS and PFS were 8·6 months and 3·0 months, respectively. The best overall RR was 20% (five of 25). In total, 16 grade 3/4 severe adverse events (SAEs) occurred; however, all patients recovered. Patients who achieved partial response or stable disease as best response had longer OS than those with progressive disease (median OS not reached and 3·3 months, respectively; P < 0·001). Patients who did not experience SAEs showed longer OS than those who did (median OS 18·8 months and 7·5 months, respectively; P < 0·05). Patients with distant metastasis had shorter median OS than those with locoregional disease, but without statistically significant difference.

CONCLUSIONS

ERB showed a promising RR and is a potential candidate for second-line treatment for patients with CAS, after treatment with taxanes. However, owing to the occurrence of SAEs in over half of the participants, caution should be exercised regarding ERB use in elderly patients. What is already known about this topic? Taxanes are the current first-line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. No effective therapy for taxane-resistant CAS has been established thus far. Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes. What does this study add? In our single-arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression-free survival were 8·6 and 3·0 months, respectively. Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively. Although 16 grade 3/4 severe adverse events occurred, all patients recovered. Eribulin showed a promising response rate and is a potential candidate for second-line treatment in CAS after taxane treatment. Linked Comment: Smrke and Benson. Br J Dermatol 2020; 183:797-798.

Definitive chemoradiotherapy for squamous cell carcinoma of the esophagus: outcomes for borderline-resectable disease

Definitive chemoradiotherapy (dCRT) is the standard treatment for unresectable esophageal cancer. Induction chemotherapy has been actively investigated for borderline-resectable and unresectable disease, but the superiority over dCRT has yet to be confirmed. The purpose of this study was to evaluate the outcome of dCRT with special interest in borderline-resectable disease. Patients with esophageal cancer treated with dCRT between January 2004 and November 2016 were included in this retrospective analysis. Chemotherapy consisted of two cycles of cisplatin (70-75 mg/m2) on day 1 and 5-fluorouracil (700-1000 mg/m2 per day) on days 1-4 or low-dose cisplatin (10 mg/m2 per day) and 5-fluorouracil (175 mg/m2 per day) for 20 days. Radiotherapy was given with a daily fraction of 1.8-2 Gy to a total dose of 50-70 Gy. A total of 104 patients were included: 34 were resectable, 35 were borderline-resectable and 35 were unresectable. Complete response was achieved in 44 patients (42%). Eighteen patients (17%) suffered Grade 2 or greater cardiopulmonary toxicity and seven patients (7%) suffered Grade 3 cardiopulmonary toxicity. At the time of this analysis, 59 patients were dead and 45 were censored. The 3-year overall survival proportions for resectable, borderline-resectable and unresectable patients were 64%, 46% and 21%, respectively. The overall survival for borderline-resectable patients with complete response and noncomplete response was significantly different (P < 0.001), with 3-year survival of 70% and 8%, respectively. The overall survival for complete response patients with borderline-resectable disease was encouraging. Further investigation to find a subgroup fit for esophagus-preserving treatment is warranted.

Long-term results of intensity-modulated radiotherapy with three dose-fractionation regimens for localized prostate cancer

We evaluated long-term outcomes of three protocols of intensity-modulated radiation therapy (IMRT) for localized prostate cancer. Between 2005 and 2014, 348 patients were treated with 5-field IMRT. The first 74 patients were treated with a daily fraction of 2.0 Gy to 74 Gy (low-risk prostate cancer) or 78 Gy (intermediate- or high-risk prostate cancer); then 101 patients were treated with 2.1-Gy daily fractions to 73.5 or 77.7 Gy. More recently, 173 patients were treated with 2.2-Gy fractions to 72.6 or 74.8 Gy. The median age of all patients was 70 years and the median follow-up period was 82 months. The median follow-up periods were 124 months in the 2.0-Gy group, 98 months in the 2.1-Gy group, and 69 months in the 2.2-Gy group. The overall and prostate-specific antigen (PSA) failure-free survival (PSA-FFS) rates were, respectively, 89 and 68% at 10 years for the 2.0-Gy group, 91 and 84% at 8 years for the 2.1-Gy group, and 93 and 92% at 6 years for the 2.2-Gy group. The PSA-FFS rate for high-risk patients in all groups was 80% at 7 years. The cumulative incidences of Grade ≥2 late genitourinary (GU) and gastrointestinal (GI) toxicity were, respectively, 7.2 and 12.4% at 10 years for the 2.0-Gy group, 7.4 and 14.1% at 8 years for the 2.1-Gy group, and 7.1 and 7.9% at 6 years for the 2.2-Gy group. All three fractionation schedules yielded good tumor control with acceptable toxicities.

Chemo-selection with docetaxel, cisplatin and 5-fluorouracil (TPF) regimen followed by radiation therapy or surgery for pharyngeal and laryngeal carcinoma

Background

Induction chemotherapy for patients with head and neck cancer is widely performed, and several advantages of induction chemotherapy have been reported. However, there is currently insufficient evidence to strongly recommend induction chemotherapy. In this study, we analyzed the outcomes for patients treated with induction chemotherapy and subsequent definitive treatments.

Methods

Operable patients with untreated oropharyngeal, hypopharyngeal and laryngeal squamous cell carcinoma treated with induction chemotherapy were included in this retrospective study. We conducted induction chemotherapy using docetaxel, cisplatin and 5-fluorouracil and performed subsequent surgical treatment or radiotherapy according to the response to induction chemotherapy.

Results

A total of 65 patients were included in this study, and 50 patients (76.9%) had Stage IV tumors. The response to induction chemotherapy was CR in two patients, PR in 55 patients, and SD in eight patients. The subsequent definitive treatment was radiotherapy in 60 patients, and surgery in five patients. The 3-year overall survival rates for patients who received radiotherapy and surgery were 88.4% and 75.0%, respectively (P = 0.30). The 3-year disease-free survival rates for patients who received radiotherapy and surgery were 68.0% and 0%, respectively (P = 0.01). The 3-year laryngeal dysfunction free survival rates for patients who received RT and surgery were 77.8% and 0%, respectively (P < 0.01).

Conclusions

We achieved favorable survival outcomes and high larynx preservation rates. Our results suggest that induction chemotherapy using TPF regimen is one of the optimal treatment strategies when treating head and neck cancers. Further prospective studies with a larger cohort are required to confirm our findings.

Ultrasonographic findings can identify 'pseudoprogression' under nivolumab therapy

'Pseudoprogression' is often seen in patients with melanomas who are treated with immune checkpoint inhibitors such as nivolumab or ipilimumab. We sometimes evaluate metastatic lesions by imaging tests such as computed tomography (CT) or positron emission tomography-CT. 'Pseudoprogression' usually occurs upon the initial administration, which may make it difficult for the physician to determine the disease condition. In our two cases of metastatic melanoma treated with nivolumab (antiprogrammed cell death-1 antibody), we examined the ultrasonography (US) of target lesions that could be accessed from the body surface, such as those of the regional lymph node or subcutaneous metastasis. In both cases, the US revealed a lesion approximately 10% greater in size after 40-50 days of nivolumab administration, even though the blood flow inside the tumour was reduced by about 20% within 50 days. From about 100 days after blood flow reduction was detected by US, the tumours began to decrease in size. However, contrast CT was unable to detect the association between tumour size and tumour blood flow. The present cases suggest that US could be a powerful tool for differentiating between 'pseudoprogression' and real progressive disease in patients treated with cancer immunotherapies such as those involving immune checkpoint inhibitors. The misdiagnosis of progressive disease can lead to unnecessary alterations to the current treatment. Therefore, the US findings in our study could be clinically useful and educational for physicians.

Stereotactic body radiotherapy for stage I non-small-cell lung cancer using higher doses for larger tumors: results of the second study

Background

Efficacy of stereotactic body radiotherapy (SBRT) in stage I non–small-cell lung cancer (NSCLC) has almost been established. In Japan, the protocol of 48 Gy in 4 fractions over 4 days has been most often employed, but higher doses may be necessary to control large tumors. Previously, we conducted a clinical study using SBRT for stage I NSCLC employing different doses depending on tumor diameter, which was closed in 2008. Thereafter, a new study employing higher doses has been conducted, which is reported here. The purpose of this study was to review the safety and effectiveness of the higher doses.

Methods

We escalated the total dose for the improvement of local control for large tumors. In this study, 71 patients underwent SBRT between December 2008 and April 2014. Isocenter doses of 48, 50, and 52 Gy were administered for tumors with a longest diameter of < 1.5 cm, 1.5–3 cm, and > 3 cm, respectively. It was recommended to cover 95% of the PTV with at least 90% of the isocenter dose, and in all but one cases, 95% of the PTV received at least 80% of the prescribed dose. Treatments were delivered in 4 fractions, giving 2 fractions per week. SBRT was performed with 6-MV photons using 4 non-coplanar and 3 coplanar beams.

Results

The median follow-up period was 44 months for all patients and 61 months for living patients. Overall survival (OS) was 65%, progression-free survival (PFS) was 55%, and cumulative incidence of local recurrence (LR) was 15% at 5 years. The 5-year OS was 69% for 57 stage IA patients and 53% for 14 stage IB patients (p = 0.44). The 5-year PFS was 55 and 54%, respectively (p = 0.98). The 5-year cumulative incidence of LR was 11 and 31%, respectively (p = 0.09). The cumulative incidence of Grade ≥ 2 radiation pneumonitis was 25%.

Conclusions

Our newer SBRT study yielded reasonable local control and overall survival and acceptable toxicity, but escalating the total dose did not lead to improved outcomes.

Trial registration

UMIN000027231, registered on 3 May 2017. Retrospectively registered.

Adjuvant therapy with low-dose interferon-beta for stage II and III melanoma: results of a retrospective analysis

Interferon (IFN)-alfa as an adjuvant therapy has been found to improve relapse-free survival in patients with malignant melanoma (MM). However, the efficacy of IFN-beta has not been studied in detail. This study evaluated the contribution of adjuvant IFN-beta therapy to improvements in the prognosis of patients with MM. We reviewed 63 patients with resected stage II/III primary MM at our institution. Of these, 36 had been treated with IFN-beta adjuvant therapy (subcutaneous injection, 3 × 10⁶ IU/day, 10 days), while 27 patients had undergone observation alone. In comparisons of all patients (stage II/III), overall survival and relapse-free survival were significantly better in the IFN-beta group than in the observation group (P < 0.001 for both). The 75-month overall survival rate was 41.2% in the observation group and 68.7% in the IFN-beta group. Adjuvant therapy with IFN-beta may become a new treatment option for patients with stage II/III MM.

Multiple skin cancers in patients with mycosis fungoides after long-term ultraviolet phototherapy

Phototherapy is a useful noninvasive therapy, but it can induce cutaneous malignant tumours, including squamous cell carcinoma (SCC) and basal cell carcinoma (BCC). We report on a 79-year-old man who had long-standing mycosis fungoides for 40 years, which had been treated with psoralen ultraviolet A therapy for 37 years at a dose of approximately 5000 J/cm² . Approximately 6 years before presentation, numerous types of cutaneous malignancies, including actinic keratosis, BCC and SCC, had begun to develop all over the patient's body. We hypothesized that he was experiencing a pathogenesis similar to patients with xeroderma pigmentosum (XP), and we therefore assessed his DNA repair capacity. Based on these investigations, the patient was eventually diagnosed as non-XP, even though we detected that his DNA repair capacity was slightly lower than that of normal controls, which may have led to the skin cancers. We speculate that multiple skin malignancies can be induced by long-term phototherapy in patients with slightly impaired DNA repair capacity.

Efficacy of stereotactic radiotherapy for brain metastases using dynamic jaws technology in the helical tomotherapy system

Objective:

Dynamic jaws (DJ) are expected to be useful in stereotactic radiotherapy (SRT) for brain metastases (BM). The efficacy and optimal dose fractionation were investigated.

Methods:

In a planning study, 63 treatment plans were generated for the following 3 conditions: 1.0-cm fixed jaws (FJ), 2.5-cm FJ and 2.5-cm DJ. In a clinical study, 30 Gy/3 fr, 35 Gy/5 fr or 37.5 Gy/5 fr were prescribed depending on tumour size. Clinical results of groups treated with 2.5-cm DJ plans and 1.0-cm FJ were compared.

Results:

In the planning study, the treatment times in 2.5-cm DJ and FJ plans were less than that in 1.0-cm FJ plans (p < 0.001). The brain doses in 1.0-cm FJ plans and 2.5-cm DJ plans were smaller than those in 2.5-cm FJ plans (p < 0.05). In the clinical study, 34 patients with 68 BM were treated with SRT. Of those, 15 patients with 34 BM were treated with 2.5-cm DJ plans and 19 patients with 34 BM were treated with 1.0-cm FJ plans. The overall survival and local tumour control (LC) rates were 52 and 93% at 12 months, respectively. The DJ system achieved favourable LC and 29% shorter treatment time compared with the FJ system (p < 0.001). Grade 2 or 3 necrosis occurred more frequently in patients with 15 cc or larger tumour volumes (p = 0.05).

Conclusion:

DJ technology enables treatment time to be reduced without worsening the dose distribution and clinical efficacy. The prescribed doses in this study may be acceptable for patients with small tumour volumes.

Advances in knowledge:

DJ technology enables treatment time to be reduced without worsening the dose.

Definitive Radiotherapy Following Induction Chemotherapy for Hypopharyngeal Cancer: Selecting Candidates for Organ-Preserving Treatment Based on the Response to Induction Chemotherapy

The outcomes of induction chemotherapy followed by radiotherapy for hypopharyngeal carcinoma were analyzed to determine whether response to induction chemotherapy could be a useful parameter for selecting candidates for organ-preserving therapy.Forty-three patients with hypopharyngeal carcinoma were treated with definitive radiotherapy with or without concurrent chemotherapy following induction chemotherapy. The predominant induction chemotherapy regimens involved cisplatin and 5-fluorouracil with or without docetaxel. The patients that responded to the induction chemotherapy received definitive organ-preserving treatment. Patients who did not respond to induction chemotherapy were considered for surgery, but only those patients who underwent definitive radiotherapy were analyzed in this study. Conventional radiotherapy was administered in all patients. The associations between clinical parameters including age, sex, performance status (PS), tumor site, T-category, N-category, stage, the regimen of induction chemotherapy, the response to induction chemotherapy, the presence/absence of concurrent chemotherapy, overall survival (OS), and local control (LC) were analyzed.Among the surviving patients, the follow-up period ranged from 10-145 months (median: 46 months). The 3-year OS and LC rates for all 43 patients were 61% and 70%, respectively. The 3-year OS and LC rates of the responders were 73% and 81%, respectively, whereas those of the non-responders were 29% and 40%, respectively. In multivariate analysis, only PS was correlated with overall survival (p=0.03). The complication rates were acceptable in all groups.Responders to induction chemotherapy appear to be good candidates for definitive organ-preserving treatment. Chemoselection appears to aid treatment selection in patients with hypopharyngeal carcinoma.

Dose-volume histogram comparison between static 5-field IMRT with 18-MV X-rays and helical tomotherapy with 6-MV X-rays

We treated prostate cancer patients with static 5-field intensity-modulated radiation therapy (IMRT) using linac 18-MV X-rays or tomotherapy with 6-MV X-rays. As X-ray energies differ, we hypothesized that 18-MV photon IMRT may be better for large patients and tomotherapy may be more suitable for small patients. Thus, we compared dose-volume parameters for the planning target volume (PTV) and organs at risk (OARs) in 59 patients with T1-3 N0M0 prostate cancer who had been treated using 5-field IMRT. For these same patients, tomotherapy plans were also prepared for comparison. In addition, plans of 18 patients who were actually treated with tomotherapy were analyzed. The evaluated parameters were homogeneity indicies and a conformity index for the PTVs, and D2 (dose received by 2% of the PTV in Gy), D98, Dmean and V10-70 Gy (%) for OARs. To evaluate differences by body size, patients with a known body mass index were grouped by that index ( <21; 21-25; and >25 kg/m(2)). For the PTV, all parameters were higher in the tomotherapy plans compared with the 5-field IMRT plans. For the rectum, V10 Gy and V60 Gy were higher, whereas V20 Gy and V30 Gy were lower in the tomotherapy plans. For the bladder, all parameters were higher in the tomotherapy plans. However, both plans were considered clinically acceptable. Similar trends were observed in 18 patients treated with tomotherapy. Obvious trends were not observed for body size. Tomotherapy provides equivalent dose distributions for PTVs and OARs compared with 18-MV 5-field IMRT. Tomotherapy could be used as a substitute for high-energy photon IMRT for prostate cancer regardless of body size.

Helical and Static-port Tomotherapy Using the Newly-developed Dynamic Jaws Technology for Lung Cancer

With the newly developed dynamic jaws technology, radiation dose for the cranio-caudal edges of a target can be lowered in the treatment with tomotherapy. We compared dynamic-jaw- and fixed-jaw-mode plans for lung cancer. In 35 patients, four plans using the 2.5-cm dynamic-, 2.5-cm fixed-, 5.0-cm dynamic-, and 5.0-cm fixed-jaw modes were generated. For 10 patients with upper lobe stage I lung cancer, the helical tomotherapy mode was used. Fifty-six Gy in 8 fractions was prescribed as a minimum coverage dose for 95% of the target (D95%). For 25 patients with locally advanced lung cancer, plans using four static ports (TomoDirect® mode) were made. Sixty Gy in 30 daily fractions for the primary tumor and swollen lymph nodes and 51 Gy in 30 fractions for prophylactic lymph node areas were prescribed as median doses. The mean conformity index of the planning target volume were similar among the four plans. The mean V5 Gy of the lung for 2.5-cm dynamic-, 2.5-cm fixed-, 5.0-cm dynamic-, and 5.0-cm fixed-jaw mode plans were 18.5%, 21.8%, 20.1%, and 29.4%, respectively (p < 0.0001), for patients with stage I lung cancer, and 37.3%, 38.7%, 40.4%, and 44.0%, respectively (p < 0.0001), for patients with locally advanced lung cancer. The mean V5 Gy of the whole body was 1,826, 2,143, 1,983, and 2,939 ml, respectively (p < 0.0001), for patients with stage I lung cancer and 4,849, 5,197, 5,220, and 6,154 ml, respectively (p < 0.0001), for patients with locally advanced lung cancer. Treatment time was reduced by 21-39% in 5.0-cm dynamic-jaw plans compared to 2.5-cm plans. Regarding dose distribution, 2.5-cm dynamic-jaw plans were the best, and 5.0-cm dynamic-jaw plans were comparable to 2.5-cm fixed-jaw plans with shorter treatment times. The dynamic-jaw mode should be used instead of the conventional fixed-jaw mode in tomotherapy for lung cancer.