PENTEC Organ-Specific Report: Brain and Brain Stem Necrosis After Reirradiation for Recurrent Childhood Primary Central Nervous System Tumors: A PENTEC Comprehensive Review.

PURPOSE: Reirradiation is increasingly used in children and adolescents/young adults (AYA) with recurrent primary central nervous system tumors. The Pediatric Normal Tissue Effects in the Clinic (PENTEC) reirradiation task force aimed to quantify risks of brain and brain stem necrosis after reirradiation. METHODS AND MATERIALS: A systematic literature search using the PubMed and Cochrane databases for peer-reviewed articles from 1975 to 2021 identified 92 studies on reirradiation for recurrent tumors in children/AYA. Seventeen studies representing 449 patients who reported brain and brain stem necrosis after reirradiation contained sufficient data for analysis. While all 17 studies described techniques and doses used for reirradiation, they lacked essential details on clinically significant dose-volume metrics necessary for dose-response modeling on late effects. We, therefore, estimated incidences of necrosis with an exact 95% CI and qualitatively described data. Results from multiple studies were pooled by taking the weighted average of the reported crude rates from individual studies. RESULTS: Treated cancers included ependymoma (n = 279 patients; 7 studies), medulloblastoma (n = 98 patients; 6 studies), any CNS tumors (n = 62 patients; 3 studies), and supratentorial high-grade gliomas (n = 10 patients; 1 study). The median interval between initial and reirradiation was 2.3 years (range, 1.2-4.75 years). The median cumulative prescription dose in equivalent dose in 2-Gy fractions (EQD22; assuming α/ß value = 2 Gy) was 103.8 Gy (range, 55.8-141.3 Gy). Among 449 reirradiated children/AYA, 22 (4.9%; 95% CI, 3.1%-7.3%) developed brain necrosis and 14 (3.1%; 95% CI, 1.7%-5.2%) developed brain stem necrosis with a weighted median follow-up of 1.6 years (range, 0.5-7.4 years). The median cumulative prescription EQD22 was 111.4 Gy (range, 55.8-141.3 Gy) for development of any necrosis, 107.7 Gy (range, 55.8-141.3 Gy) for brain necrosis, and 112.1 Gy (range, 100.2-117 Gy) for brain stem necrosis. The median latent period between reirradiation and the development of necrosis was 5.7 months (range, 4.3-24 months). Though there were more events among children/AYA undergoing hypofractionated versus conventionally fractionated reirradiation, the differences were not statistically significant (P = .46). CONCLUSIONS: Existing reports suggest that in children/AYA with recurrent brain tumors, reirradiation with a total EQD22 of about 112 Gy is associated with an approximate 5% to 7% incidence of brain/brain stem necrosis after a median follow-up of 1.6 years (with the initial course of radiation therapy being given with conventional prescription doses of ≤2 Gy per fraction and the second course with variable fractionations). We recommend a uniform approach for reporting dosimetric endpoints to derive robust predictive models of late toxicities following reirradiation.

Parents' preferences for respite care of children with medical complexity.

BACKGROUND: The number of children with medical complexity (CMC) is increasing worldwide. For these children and their families, various forms of support are legislated; among them, short-stay respite care has a great unmet need. We examined such children's parents' preferences for respite care and their willingness to pay. METHODS: We used discrete choice experiments (DCEs) to estimate the parents' preferences and willingness to pay. Parents whose children used overnight short-stay respite services answered a questionnaire to compare two hypothetical facilities of respite care having seven attributes and three levels. The DCE data was analyzed using the conditional logit model. The willingness to pay was calculated based on DCE estimates. RESULTS: A total of 70 parents participated in this study and mean age of their children was 7.8 years (standard deviation [SD] 4.3). Among those children, 67 (96%) had the severest certification of disability, and 27 (38%) used a ventilator at home. We found that the parents' highest preferences was the best level of medical care level that can manage ventilators (coefficient 1.61, 95% confidence interval [CI]: 1.32-1.90). The better and best level of medical care, daily care, education/nursing, and emergency care were preferred over basic quality services. Willingness to pay for the best level of medical care was approximately 75,367 JPY per night. CONCLUSION: This study shows a need for respite care that can deliver high-level medical care, especially for the management of ventilators, to CMC. This finding can serve as a basis for promoting respite care services.

Changes in satisfaction and anxiety about radiotherapy for pediatric cancer by two-step audio-visual instruction.

Objectives: Although radiotherapy is an essential component of pediatric cancer treatment, inadequate radiotherapy information for childhood cancer and unusual treatment situations can negatively affect parental perceptions and emotions. This study aims to investigate the effect of two-step audio-visual instruction system effects introduced by our institution on parent satisfaction and anxiety when initiating radiotherapy. Methods: The two-step audio-visual instruction system comprised instructive animation using patient avatars and a live video system. The live video system has a 55-inch-wide monitor, and a no-latency sound module. Parents in the radiotherapy division can view the patient in the treatment room through the live video system. This prospective study compared satisfaction and anxiety about radiotherapy introduction before and after two-step audio-visual instruction. We enrolled 20 parents whose child underwent radiotherapy, and they completed a set of questionnaires-Client Satisfaction Questionnaire, State-Trait Anxiety Inventory, and original questionnaires about radiotherapy. Results: Satisfaction scores improved significantly after two-step audio visual instruction (25.5 ± 3.4) compared with those before the instruction (27.7 ± 3.1) (p = <0.01). Anxiety scores also decreased significantly after the instruction (50 ± 9) compared with those before the instruction (54 ± 11) (p = 0.004). However, anxiety-related personality trait scores did not change drastically before and after viewing (48 ± 8.5 vs. 49 ± 7.5) (p = 0.419). Conclusion: This single-arm prospective study indicates that two-step audio-visual instruction for radiotherapy is effective in improving parents' anxiety about radiotherapy introductions. However, large-scale and comparative studies are warranted to generalize the benefit of two-step audio visual instruction.

Outcomes of intracranial non-germinomatous germ cell tumors: a retrospective Asian multinational study on treatment strategies and prognostic factors.

PURPOSE: Non-germinomatous germ cell tumors (NGGCTs) are rare pediatric conditions. This multicenter study using Asian multinational patient data investigated treatment outcomes and prognostic factors for NGGCTs. METHODS: Medical records of 251 patients with NGGCTs treated from 1995 to 2015 were retrospectively analyzed from participating centers in Asian countries (Korea, Taiwan, Singapore, and Japan). RESULTS: The median follow up was 8.5 years (95% CI 7.8-9.9). In the total cohort, 5-year event-free survival (EFS) and overall survival (OS) rates were 78.2% and 85.4%, respectively. In 17.9% of the patients, diagnosis was determined by tumor markers alone (alpha-fetoprotein ≥ 10 ng/mL (Korea) or > 25 ng/mL (Taiwan and Singapore), and/or ß-human chorionic gonadotropin (ß-hCG) ≥ 50 mIU/mL). Patients with immature teratomas and mature teratomas comprised 12.0% and 8.4%, respectively. The 5-year EFS rate was higher in patients with histologically confirmed germinoma with elevated ß-hCG (n = 28) than those in patients with malignant NGGCTs (n = 127). Among malignant NGGCTs, patients with choriocarcinoma showed the highest 5-year OS of 87.6%, while yolk sac tumors showed the lowest OS (68.8%). For malignant NGGCT subgroups, an increase in serum ß-hCG levels by 100 mIU/mL was identified as a significant prognostic factor associated with the EFS and OS. CONCLUSION: Our result shows excellent survival outcomes of overall CNS NGGCT. However, treatment outcome varied widely across the histopathologic subgroup of NGGCT. Hence, this study suggests the necessity for accurate diagnosis by surgical biopsy and further optimization of diagnosis and treatment according to the histopathology of NGGCTs. Future clinical trials should be designed for individualized treatments for different NGGCTs subsets.

Outcomes of intracranial germinoma-A retrospective multinational Asian study on effect of clinical presentation and differential treatment strategies.

BACKGROUND: This multinational study was conducted to report clinical presentations and treatment strategies in patients with intracranial germinomas across selected Asian centers, including failure patterns, risk factors, and outcomes. METHODS: A retrospective data collection and analysis of these patients, treated between 1995 and 2015 from eight healthcare institutions across four countries was undertaken. RESULTS: From the results, 418 patients were analyzed, with a median follow-up of 8.9 years; 79.9% of the patients were M0, and 87.6% had ß-human chorionic gonadotropin values <50 mIU/mL. The 5/10-year overall survival (OS) and recurrence-free survival (RFS) rates were 97.2%/96.2% and 89.9%/86.9%, respectively. RFS was predicted by the radiotherapy (RT) field, with focal RT having the worst outcome, whereas chemotherapy usage had no impact on survival. Among patients who received chemotherapy, response to chemotherapy did not predict survival outcomes. In M0 patients, primary basal ganglia tumors predicted a worse RFS. In patients with bifocal tumors, an extended field RT was associated with better outcomes. In multivariable analysis, only RT fields were associated with RFS. In relapsed patients, salvage rates were high at 85.7%. Additionally, patients who received salvage RT had a better outcome (91.6% vs. 66.7%). CONCLUSIONS: Survival outcomes of patients with germinoma were excellent. Thus, the focus of treatment for intracranial germinoma should be on survivorship. Further studies are warranted to find the optimal intensity and volume of radiation, including the role of chemotherapy in the survival of patients with intracranial germinomas, considering age, primary tumor location, and extent of disease.

Proton beam therapy for children and adolescents and young adults (AYAs): JASTRO and JSPHO Guidelines.

Children and adolescents and young adults (AYAs) with cancer are often treated with a multidisciplinary approach. This includes use of radiotherapy, which is important for local control, but may also cause adverse events in the long term, including second cancer. The risks for limited growth and development, endocrine dysfunction, reduced fertility and second cancer in children and AYAs are reduced by proton beam therapy (PBT), which has a dose distribution that decreases irradiation of normal organs while still targeting the tumor. To define the outcomes and characteristics of PBT in cancer treatment in pediatric and AYA patients, this document was developed by the Japanese Society for Radiation Oncology (JASTRO) and the Japanese Society of Pediatric Hematology/Oncology (JSPHO).

Tertiary lymphoid tissue in early-stage IgG4-related tubulointerstitial nephritis incidentally detected with a tumor lesion of the ureteropelvic junction: a case report.

BACKGROUND: IgG4-related kidney disease causes renal impairment of unknown pathogenesis that may progress to kidney failure. Although ectopic germinal centers contribute to the pathogenesis of the head and neck lesions of IgG4-related disease, the presence of tertiary lymphoid tissue (TLT) containing germinal centers in IgG4-RKD has rarely been reported. CASE PRESENTATION: We report a 72-year-old Japanese man who had IgG4-related tubulointerstitial nephritis (TIN) with TLT formation incidentally detected in a resected kidney with mass lesion of IgG4-related ureteritis in the ureteropelvic junction. During follow-up for past surgical resection of a bladder tumor, renal dysfunction developed and a ureter mass was found in the right ureteropelvic junction, which was treated by nephroureterectomy after chemotherapy. Pathology revealed no malignancy but abundant IgG4-positive cell infiltration, obliterative phlebitis and storiform fibrosis, confirming the diagnosis of IgG4-related ureteritis. In the resected right kidney, lymphoplasmacytes infiltrated the interstitium with focal distribution in the renal subcapsule and around medium vessels without storiform fibrosis, suggesting the very early stage of IgG4-TIN. Lymphocyte aggregates were also detected at these sites and consisted of B, T, and follicular dendritic cells, indicating TLT formation. IgG4-positive cells infiltrated around TLTs. CONCLUSIONS: Our case suggests that TLT formation is related with the development of IgG4-TIN and our analysis of distribution of TLT have possibility to elucidate IgG4-TIN pathophysiology.

Outcome and Late Complications of Hepatoblastomas Treated Using the Japanese Study Group for Pediatric Liver Tumor 2 Protocol.

PURPOSE: We report here the outcomes and late effects of the Japanese Study Group for Pediatric Liver Tumors (JPLT)-2 protocol, on the basis of cisplatin-tetrahydropyranyl-adriamycin (CITA) with risk stratification according to the pretreatment extent of disease (PRETEXT) classification for hepatoblastoma (HB). PATIENTS AND METHODS: From 1999 to 2012, 361 patients with untreated HB were enrolled. PRETEXT I/II patients were treated with up-front resection, followed by low-dose CITA (stratum 1) or received low-dose CITA, followed by surgery and postoperative chemotherapy (stratum 2). In the remaining patients, after 2 cycles of CITA, responders received the CITA regimen before resection (stratum 3), and nonresponders were switched to ifosfamide, pirarubicin, etoposide, and carboplatin (ITEC; stratum 4). Intensified chemotherapeutic regimens with autologous hematopoietic stem-cell transplantation (SCT) after resection were an optional treatment for patients with refractory/metastatic disease. RESULTS: The 5-year event-free and overall survival rates of HB patients were 74.2% and 89.9%, respectively, for stratum 1, 84.8% and 90.8%%, respectively, for stratum 2, 71.6% and 85.9%%, respectively, for stratum 3, and 59.1% and 67.3%%, respectively, for stratum 4. The outcomes for CITA responders were significantly better than those for nonresponders, whose outcomes remained poor despite salvage therapy with a second-line ITEC regimen or SCT. The late effects, ototoxicity, cardiotoxicity, and delayed growth, occurred in 61, 18, and 47 patients, respectively. Thirteen secondary malignant neoplasms (SMNs), including 10 leukemia, occurred, correlating with higher exposure to pirarubicin and younger age at diagnosis. CONCLUSION: The JPLT-2 protocol achieved up-front resectability in PRETEXT I/II patients with no annotation factors, and satisfactory survival in patients who were CITA responders in the remaining patients. However, outcomes for CITA nonresponders were unsatisfactory, despite therapy intensification with ITEC regimens and SCT. JPLT-2 had a relatively low incidence of cardiotoxicity but high rates of SMNs.

Definitive Tumor Resection after Myeloablative High Dose Chemotherapy Is a Feasible and Effective Option in the Multimodal Treatment of High-Risk Neuroblastoma: A Single Institution Experience.

BACKGROUND/PURPOSE: The delayed local treatment approach (DL) in high-risk neuroblastoma (HR-NB) refers to the process in which tumor resection is performed after the completion of all the courses of chemotherapy, including myeloablative high-dose chemotherapy (HDC). Alternatively, in the conventional local treatment approach (CL), tumor resection is performed during induction chemotherapy. In this study, we compared the surgical outcomes in HR-NB patients treated by CL and DL. METHOD: Forty-seven patients with abdominal HR-NB underwent primary tumor resection from 2002 to 2018. The timing of surgery was generally determined by following the trials and guidelines available at the time. The outcomes and surgical complications between the two strategies were compared. RESULT: Operation time, blood loss, and postoperative WBC counts were lower in the DL group (n = 25) when compared to the CL group (n = 22), statistical significance notwithstanding. Major vascular structures were less frequently encased in the DL group tumors, while immediate surgical complications were significantly more frequent in the CL group (P < 0.05). Furthermore, the 3-year EFSs were 50.0% and 53.9% in the DL and CL groups, respectively. CONCLUSION: DL appears to be a feasible and effective treatment option for HR-NB. Nonetheless, further verifications using larger cohorts are warranted. LEVEL OF EVIDENCE: Treatment study, Level III.

Liver phantom design and dosimetric verification in participating institutions for a proton beam therapy in patients with resectable hepatocellular carcinoma: Japan Clinical Oncology Group trial (JCOG1315C).

BACKGROUND AND PURPOSE: In Japan, the first domestic clinical trial of proton beam therapy for the liver was initiated as the Japan Clinical Oncology Group trial (JCOG1315C: Non-randomized controlled study comparing proton beam therapy and hepatectomy for resectable hepatocellular carcinoma). Purposes of this study were to develop a new dosimetric verification system and to carry out a credentialing for the JCOG1315C clinical trial. MATERIALS AND METHODS: Accuracy and differences in doses in proton treatment planning among participating institutions were surveyed and investigated. We designed and developed a suitable water tank-type liver phantom for a dosimetric verification of proton beam therapy for liver. In a visiting survey of five institutions participating in the clinical trial, we performed the dosimetric verification using the liver phantom and an air-filled ionization chamber. RESULTS: The shape of the dose distributions calculated in proton treatment planning was characteristic and dependent on the manufacturers of the proton beam therapy system, the proton treatment planning system and the setup at the participating institutions. Widths of the lateral penumbra were 5.8-12.7 mm among participating institutions. The accuracy between the calculated and the measured doses in the proton irradiation was within 3% at five measurement points including both points on the isocenter and off the isocenter. CONCLUSIONS: These findings confirmed the accuracy of the delivery doses in the institutions participating in the clinical trial, and the clinical trial with integration of all institutions (five institutions) could be initiated.

Perspectives of value-based policy making in child health care in Japan.

In Japan, epidemiological transition has profoundly influenced the priorities of child healthcare. As pediatric care is shifting from a disease-driven curative approach to an integrated approach, the value of child health care now needs to be redefined with an integrated scope. With the trend to emphasize a rational judgement on the social value in terms of resource allocation and health policy, a value-based approach is necessary for child health care. This study aims to provide an overview and perspective of value-based policy making in child health care, under a context of epidemiological transition, health care system and social changes. The current methodology scheme of CEA and outcome evaluation has limitations, not meeting the urgent need of the application. The outcomes of child health care are no longer limited in clinical and health indicators such as survival rate, cure rate and health related quality of life, but also various aspects other than health, such as education, well-being of children and their primary caregivers, especially when treatment of diseases is no longer the dominant role of health care. Such the evaluation should reflect the impacts of the integrated approach in a long-term scope.

Preliminary results of proton radiotherapy for pediatric rhabdomyosarcoma: a multi-institutional study in Japan.

To evaluate preliminary results of proton radiotherapy (PRT) for pediatric patients with rhabdomyosarcoma (RMS). From 1987 to 2014, PRT was conducted as initial radiotherapy in 55 patients (35 males, 20 females, median age 5 years, range 0-19) with RMS at four institutes in Japan. Thirty-one, 18, and six patients had embryonal, alveolar, and other RMS, respectively. One, 11, 37, and six patients were in IRSG groups I, II, III, and IV, respectively, and the COG risk group was low, intermediate, and high for nine, 39, and seven patients, respectively. The irradiation dose was 36-60 GyE (median: 50.4 GyE). The median follow-up period was 24.5 months (range: 1.5-320.3). The 1- and 2-year overall survival rates were 91.9% (95% CI: 84.3-99.5%) and 84.8% (95% CI 75.2-94.3%), respectively, and these rates were 100% and 100%, 97.1% and 90.1%, and 57.1% and 42.9% for COG low-, intermediate-, and high-risk groups, respectively. There were 153 adverse events of Grade ≥3, including 141 hematologic toxicities in 48 patients (87%) and 12 radiation-induced toxicities in nine patients (16%). Proton-specific toxicity was not observed. PRT has the same treatment effect as photon radiotherapy with tolerable acute radiation-induced toxicity.

The role of pulmonary metastasectomy for hepatoblastoma in children with metastasis at diagnosis: Results from the JPLT-2 study.

BACKGROUND/PURPOSE: The purpose of this study was to clarify the role of pulmonary metastasectomy in hepatoblastomas with lung metastasis at diagnosis. We reviewed cases enrolled in the JPLT-2 study. METHODS: A total of 360 cases with hepatoblastoma were enrolled. The clinical courses and outcome of 60 cases with pulmonary metastasis at diagnosis were reviewed, focusing on metastasectomy. RESULTS: Induction chemotherapy resulted in eradication of nodules in 26, residual nodules in 33, and early treatment-related death in one. Of the 33 cases with residual nodules, 11 underwent complete resection of the lung lesions, and among these, progression was reported in five. Complete resection of the liver tumor was not achieved in two of these. Three underwent incomplete resection of lung nodules, eventually leading to progression. Twelve cases with incomplete or no liver tumor resection progressed regardless of the status of lung lesions. Contrarily, among patients who underwent complete resection of the liver tumor, half were cured without metastasectomy. CONCLUSIONS: Metastasectomy for residual pulmonary nodules after induction chemotherapy is effective provided that the liver tumor could be completely resected. TYPE OF STUDY: Prospective Cohort Study. LEVEL OF EVIDENCE: Level II.

Long-term follow-up after proton beam therapy for pediatric tumors: a Japanese national survey.

Proton beam therapy (PBT) is a potential new alternative to treatment with photon radiotherapy that may reduce the risk of late toxicity and secondary cancer, especially for pediatric tumors. The goal of this study was to evaluate the long-term benefits of PBT in cancer survivors. A retrospective observational study of pediatric patients who received PBT was performed at four institutions in Japan. Of 343 patients, 62 were followed up for 5 or more years. These patients included 40 males and 22 females, and had a median age of 10 years (range: 0-19 years) at the time of treatment. The irradiation dose ranged from 10.8 to 81.2 GyE (median: 50.4 GyE). The median follow-up period was 8.1 years (5.0-31.2 years). The 5-, 10- and 20-year rates for grade 2 or higher late toxicities were 18%, 35% and 45%, respectively, and those for grade 3 or higher late toxicities were 6%, 17% and 17% respectively. Univariate analysis showed that the irradiated site (head and neck, brain) was significantly associated with late toxicities. No malignant secondary tumors occurred within the irradiated field. The 10- and 20-year cumulative rates for all secondary tumors, malignant secondary tumors, and malignant nonhematologic secondary tumors were 8% and 16%, 5% and 13%, and 3% and 11%, respectively. Our data indicate that PBT has the potential to reduce the risk of late mortality and secondary malignancy. Longer follow-up is needed to confirm the benefits of PBT for pediatric tumors.

Proton beam therapy for pediatric malignancies: a retrospective observational multicenter study in Japan.

Recent progress in the treatment for pediatric malignancies using a combination of surgery, chemotherapy, and radiotherapy has improved survival. However, late toxicities of radiotherapy are a concern in long-term survivors. A recent study suggested reduced secondary cancer and other late toxicities after proton beam therapy (PBT) due to dosimetric advantages. In this study, we evaluated the safety and efficacy of PBT for pediatric patients treated in Japan. A retrospective observational study in pediatric patients who received PBT was performed. All patients aged <20 years old who underwent PBT from January 1983 to August 2014 at four sites in Japan were enrolled in the study. There were 343 patients in the study. The median follow-up periods were 22.6 months (0.4-374.3 months) for all patients and 30.6 months (0.6-374.3 months) for survivors. The estimated 1-, 3-, 5-, and 10-year survival rates were 82.7% (95% CI: 78.5-87.0%), 67.4% (61.7-73.2%), 61.4% (54.8-67.9%), and 58.7% (51.5-65.9%), respectively. Fifty-two events of toxicity ≥ grade 2 occurred in 43 patients. Grade 4 toxicities of myelitis, visual loss (two cases), cerebral vascular disease, and tissue necrosis occurred in five patients. This study provides preliminary results for PBT in pediatric patients in Japan. More experience and follow-up with this technique are required to establish the efficacy of PBT in this patient population.

Dose escalation study of proton beam therapy with concurrent chemotherapy for stage III non-small cell lung cancer.

The purpose of this study is to determine the recommended dose (RD) of proton beam therapy (PBT) for inoperable stage III non-small cell lung cancer (NSCLC). We tested two prescribed doses of PBT: 66 Gy (relative biological effectiveness [RBE]) in 33 fractions and 74 Gy (RBE) in 37 fractions in arms 1 and 2, respectively. The planning target volume (PTV) included the primary tumor and metastatic lymph nodes with adequate margins. Concurrent chemotherapy included intravenous cisplatin (60 mg/m(2) , day 1) and oral S-1 (80, 100 or 120 mg based on body surface area, days 1-14), repeated as four cycles every 4 weeks. Dose-limiting toxicity (DLT) was defined as grade 3 or severe toxicities related to PBT during days 1-90. Each dose level was performed in three patients, and then escalated to the next level if no DLT occurred. When one patient developed a DLT, three additional patients were enrolled. Overall, nine patients (five men, four women; median age, 72 years) were enrolled, including six in arm 1 and three in arm 2. The median follow-up time was 43 months, and the median progression-free survival was 15 months. In arm 1, grade 3 infection occurred in one of six patients, but no other DLT was reported. Similarly, no DLT occurred in arm 2. However, one patient in arm 2 developed grade 3 esophageal fistula at 9 months after the initiation of PBT. Therefore, we determined that 66 Gy (RBE) is the RD from a clinical viewpoints. (Clinical trial registration no. UMIN000005585).

Primary malignant melanoma of the trachea: A case report.

Primary cancer of the trachea is rare and accounts for only 0.1-0.4% of all newly diagnosed respiratory tract cancers, worldwide. In the present study, a case of primary tracheal malignant melanoma, a particularly rare type of cancer, is reported. A 68-year-old male presented with a cough and bloody sputum. A chest computed tomography scan revealed a 25×20×15-mm tracheal tumor, located immediately above the carina, which reduced the cross-sectional area of the trachea by ~90%. Histopathological analysis of biopsy specimens determined a diagnosis of malignant melanoma. The patient was treated with argon plasma coagulation and chemoradiotherapy, which restored airway patency, however, metastasis was detected in the lungs. The patient refused further treatment and received palliative care. Subsequently, the patient succumbed to the disease within four months. Thus, although primary malignant melanoma of the trachea is extremeley rare, the possibility should be considered during diagnosis.

A simpler method for total scalp irradiation: the multijaw-size concave arc technique.

The lateral electron-photon technique (LEPT) and intensity-modulated radiation therapy (IMRT) are commonly used for total scalp irradiation. However, the treatment planning and irradiation are laborious and time-consuming. We herein present the multijaw-size concave arc technique (MCAT) as a total scalp irradiation method that overcomes these problems. CT datasets for eight patients previously treated for angiosarcoma of the scalp were replanned using MCAT, LEPT, and IMRT. The MCAT was designed with a dynamic conformal arc for the total scalp, with a multileaf collimator to shield the brain. Two additional conformal arcs with a decreased upper-jaw position of the first dynamic conformal arc were used to reduce the cranial hotspots. The prescribed dose was 40 Gy (2 Gy/fraction) to 95% of the planning target volume (PTV, defined as the total scalp plus a 4 mm margin). MCAT was compared with LEPT and IMRT with respect to the PTV dose homogeneity (D5%-95%), underdosage (V < 90%), overdosage (V > 110%), doses to the brain, and the delivery time and monitor units (MUs) for single irradiation. We were able to formulate treatment plans for all three techniques that could deliver the prescription dose in all patients. MCAT was significantly superior to LEPT with respect to PTV dose homogeneity, overdosage, and underdosage, although MCAT was inferior to IMRT with respect to dose homogeneity and overdosage. The mean brain dose and high-dosage volume of all three techniques were low, but IMRT provided larger volume to the brain than did the other two techniques in the low dosage region. In MCAT, the mean delivery time could be reduced by approximately half or more, and the mean MUs could be reduced by at least 100 compared to the other two techniques. MCAT can achieve total scalp irradiation with substantially fewer MUs and a shorter delivery time than LEPT and IMRT.