Reirradiation of brain and skull base tumors with fractionated stereotactic radiotherapy

Etiology and management of nasopharyngeal hemorrhage after radiotherapy for nasopharyngeal carcinoma

Objective

To analyze the etiology of nasopharyngeal hemorrhage after radiotherapy for nasopharyngeal carcinoma (NPC) and evaluate the relevant management and rescue approaches.

Methods

Seventeen cases of nasopharyngeal hemorrhage caused by radiotherapy of NPC, treated between January 2015 and March 2018, were retrospectively analyzed to study the etiology of nasopharyngeal hemorrhage. The management and rescue strategies, including anterior and posterior nostril packing, endoscopic nasopharynx electrocoagulation, and digital subtraction angiography embolization, were assessed for their effectiveness.

Results

Nasopharynx hemorrhage after radiotherapy of NPC was mainly associated with erosion of the internal carotid artery or maxillary artery by the tumor. Among the 17 cases, 11 patients were treated by digital subtraction arterial angiography embolization, and 3 were treated by endoscopic nasopharynx electrocoagulation. Overall, 13 patients survived, while 4 died.

Conclusion

Anterior and posterior nostril packing, endoscopic nasopharynx electrocoagulation, and digital subtraction angiography embolization are suitable for treating nasopharyngeal hemorrhage. However, effective hemostasis depends on early identification of the bleeding vessels.

New perspectives in the treatment of adult medulloblastoma in the era of molecular oncology

Medulloblastoma is the most common central nervous system tumor in children, while it is extremely rare in adults. Multimodal treatment involving surgery, radiotherapy and chemotherapy can improve the prognosis of this disease, and recent advances in molecular biology have allowed the identification of molecular subgroups (WNT, SHH, Groups 3 and 4), each of which have different cytogenetic, mutational and gene expression signatures, demographics, histology and prognosis. The present review focuses on the state of the art for adult medulloblastoma treatment and on novel molecular advances and their future implications in the treatment of this disease.

Management of recurrent medulloblastoma in adult patients: a systematic review and recommendations

Medulloblastoma accounts for almost one-third of pediatric central nervous system (CNS) cancers, but is very rare in the adult population. As a result, adult patients with medulloblastoma are often treated according to therapies developed for children with similarly staged disease at diagnosis, based on the assumption that adult and pediatric tumors have similar properties. The purpose of this review was to summarize the evidence and to make recommendations for the management of recurrent disease in adult patients with medulloblastoma. We conducted a systematic literature search to find publications addressing treatment of recurrent medulloblastoma in adults. Current treatment strategies for adult patients with relapsed medulloblastoma are based on the results of retrospective case series and published consensus recommendations, and include maximal safe re-resection where possible, combined with chemotherapy and/or re-irradiation. We describe the results of 13 publications involving 66 adult patients treated with high-dose chemotherapy (HDCT) plus stem cell transplantation for recurrent medulloblastoma. HDCT with stem cell transplantation may be a treatment option for a small proportion of adult patients who are unlikely to benefit from conventional chemotherapy and who are fit and have their disease recurrence contained within the CNS. Potential cases in which stem cell transplantation is being considered should be discussed at a multidisciplinary tumor board which includes involvement by hematologic oncologists and transplant specialists.

Hypofractionated stereotactic radiotherapy for brain metastases larger than three centimeters

Background

To evaluate the efficacy and outcomes of hypofractionated stereotactic radiotherapy (HSRT) for brain metastases > 3 cm.

Methods

From March 2003 to October 2009, 40 patients with brain metastases larger than 3 cm were treated by HSRT. HSRT was applied in 29 patients for primary treatment and in 11 patients for rescue. Single brain metastasis was detected in 21 patients. Whole brain radiotherapy was incorporated into HSRT in 10 patients for primary treatment. HSRT boosts were applied in 23 patients. The diameters of the brain metastases ranged from 3.1 to 5.5 cm (median, 4.1 cm). The median prescribed dose (not including HSRT boosts) was 40 Gy (range, 20-53 Gy) with a median of 10 fractions (range, 4-15 fractions) to the 90% isodose line. The median dose of the boost was 20 Gy (range, 10-35 Gy) in 4 fractions (range, 2-10 fractions).

Result

The median overall survival time was 15 months. The overall survival and local control rate at 12 months was 55.3% and 94.2%, respectively. Four patients experienced local progression of large brain metastases. Nine patients died of intracranial disease progression. One patient died of radiation necrosis with brain edema.

Conclusion

HSRT was a safe and effective treatment for patients with brain metastases ranged from 3.1 to 5.5 cm. Dose escalation of HSRT boost may improve local control with an acceptable toxicity.

A contemporary review of stereotactic radiotherapy: inherent dosimetric complexities and the potential for detriment

OBJECTIVE

The advantages of highly localised, conformal treatments achievable with stereotactic radiotherapy (SRT) are increasingly being extended to extracranial sites as stereotactic body radiotherapy with advancements in imaging and beam collimation. One of the challenges in stereotactic treatment lies in the significant complexities associated with small field dosimetry and dose calculation. This review provides a comprehensive overview of the complexities associated with stereotactic radiotherapy and the potential for detriment.

METHODS

This study is based on a comprehensive review of literature accessible via PubMed and other sources, covering stereotactic radiotherapy, small-field dosimetry and dose calculation.

FINDINGS

Several key issues were identified in the literature. They pertain to dose prescription, dose measurement and dose calculation within and beyond the treatment field. Field-edge regions and penumbrae occupy a significant portion of the total field size. Spectral and dosimetric characteristics are difficult to determine and are compounded by effects of tissue inhomogeneity. Measurement of small-fields is made difficult by detector volume averaging and energy response. Available dosimeters are compared, and emphasis is given to gel dosimetry which offers the greatest potential for three-dimensional small-field dosimetry. The limitations of treatment planning system algorithms as applied to small-fields (particularly in the presence of heterogeneities) is explained, and a review of Monte Carlo dose calculation is provided, including simplified treatment planning implementations. Not incorporated into treatment planning, there is evidence that far from the primary field, doses to patients (and corresponding risks of radiocarcinogenesis) from leakage/scatter in SRT are similar to large fields.

CONCLUSIONS

Improved knowledge of dosimetric issues is essential to the accurate measurement and calculation of dose as well as the interpretation and assessment of planned and delivered treatments. This review highlights such issues and the potential benefit that may be gained from Monte Carlo dose calculation and verification via three-dimensional dosimetric methods (such as gel dosimetry) being introduced into routine clinical practice.

Relationship between volume, dose and local control in stereotactic radiosurgery of brain metastasis

The aim of this study is to analyse the efficacy of linear accelerator stereotactic radiosurgery (SRS) on prognostic factors, local control rate and survival in patients with brain metastasis. Patients with either a single metastasis or up to 4 multiple brain metastases with a maximum tumour diameter of 40 mm for each tumour and a Karnofsky Performance Status (KPS) > or = 70 were eligible for SRS. SRS was applied to 150 lesions in 86 consecutive patients with a median age of 60 years (median 1 and mean 1.7 lesions per patient, mean KPS 86). Median overall survival was 6.2 months after SRS and 9.7 months from diagnosis of brain metastasis. Multivariate analysis revealed that a KPS of 90 or more (p = 0.009) and female sex (p = 0.003) were associated with a longer survival. Radiation dose < or = 15 Gy (p = 0.017) and KPS < 90 (p = 0.013) were independent predictors of a shorter time to local failure. Five patients showed evidence of radionecrosis with a median survival of 14.8 months. Addition of WBRT neither led to improvement of survival nor to improvement of local control. Improved local control following SRS for brain metastases was associated with KPS > or =90, a radiation dose > 15 Gy and a PTV < 13 cc. The potential of hypofractionated stereotactic radiotherapy (SRT) for brain metastases of larger volume warrants further study.

Stereotactic body radiation therapy for primary, recurrent, and metastatic tumors in the head-and-neck region

PURPOSE

To determine the feasibility, safety, and efficacy of stereotactic body radiation therapy (SBRT), also known as radiosurgery, in patients with head-and-neck cancers.

METHODS AND MATERIALS

Patients with pathologically proven malignant lesions in the head-and-neck region were treated using single-dose SBRT (S-SBRT) or fractionated SBRT (F-SBRT). Radiation doses were either single-fraction 13-18 Gy for S-SBRT or 36-48 Gy in five to eight fractions for F-SBRT. Response evaluation was based on clinical examinations and computed tomography/magnetic resonance imaging scans. Pre- and post-SBRT tumor dimensions were measured in three axes, and tumor volumes were calculated. Response evaluation also was performed using World Health Organization criteria.

RESULTS

Fifty-five lesions were treated in 44 patients (25 men, 19 women). There were three groups of patients: those with primary (n = 10), recurrent (n = 21), and metastatic tumors (n = 13). The predominant histologic type was squamous cell carcinoma (n = 33). The majority of lesions were treated using F-SBRT (n = 37). Based on radiographic and clinical assessment, a 77% (complete + partial response) response rate was noted. Percentage of reduction in tumor volume was 52% +/- 38% based on follow-up scans in 24 patients. Tumor control rates at 1 year were 83.3% and 60.6% in the primary and recurrent groups, respectively. Median overall survival was 28.7, 6.7, and 5.6 months for the primary, recurrent, and metastatic groups, respectively. Radiation Therapy Oncology Group Grade 1-2 mucositis was noted in all patients treated for oropharyngeal or laryngeal lesions.

CONCLUSIONS

The SBRT in single or fractionated doses offers a viable treatment option for selected patients with primary, recurrent, and metastatic head-and-neck cancers with functional preservation.

The role of palliative radiosurgery when cancer invades the cavernous sinus

PURPOSE

Involvement of the cavernous sinus by direct invasion from skull base cancer or from metastatic spread of cancers is a challenging problem. We evaluated the role of stereotactic radiosurgery (SRS) in the treatment of patients who developed cavernous sinus metastases or direct invasion.

METHODS AND MATERIALS

We retrospectively reviewed the data from 37 patients who had cavernous sinus metastases or had cavernous sinus invasion from adjacent skull base cancers and who underwent SRS between 1992 and 2006 at the University of Pittsburgh Medical Center. The median patient age was 57.8 years. Previous adjuvant management included fractionated radiotherapy in 8, chemotherapy in 16, and both radiotherapy and chemotherapy in 5. The primary sites of metastases or invasion were nasopharyngeal carcinoma (n = 7), parotid gland carcinoma (n = 7), and metastases from systemic cancer (n = 23). The median target volume was 6.3 cm(3) (range, 0.3-33.6), and the median margin dose was 14 Gy (range, 12-20).

RESULTS

At a mean of 12.9 months (range, 0.8-63.9), 32 patients had died and 5 were living. The overall survival rate after SRS was 36.6% and 19.4% at 1 and 2 years, respectively. Progression-free survival was related to a greater marginal dose. After SRS, 12 (35.3%) of 34 patients with neurologic symptoms exhibited improvement. SRS early after diagnosis was significantly associated with improvement of cranial nerve dysfunction.

CONCLUSION

SRS is a minimally invasive palliative option for patients whose cancer has invaded the cavernous sinus. The benefits for cranial nerve deficits are best when SRS is performed early.

Hypofractionated stereotactic radiotherapy in the management of recurrent or residual medulloblastoma/PNET

PURPOSE

To evaluate the efficacy and toxicity of hypofractionated stereotactic radiotherapy in the management of locally recurrent or residual central nervous system (CNS) primitive neuroectodermal tumors (PNETs).

PATIENTS AND METHODS

Between 1991 and 2005, 12 patients with locally recurrent medulloblastoma and two patients with residual supratentorial PNET were treated with hypofractionated stereotactic conformal radiotherapy (SCRT). Nine patients were treated for first recurrence, two patients after the 2nd, and one patient after 3rd recurrence. Median age at diagnosis was 20 years (range: 4-35 years) and median age at SCRT 25 years (range: 7-41 years). Nine of 12 patients underwent resection at recurrence and 13 patients received at least one cycle of chemotherapy prior to SCRT. All received focal SCRT (30-40 Gy/6-8 #) using non-coplanar arcs (n = 6) or fixed conformal non-coplanar fields (n = 8).

RESULTS

Median overall survival was 29 months (95% CI: 6-51 months) and median progression-free survival was 12 months (95% CI: 5-19 months). Local progression-free survival at 1 and 3 years was 80% (95% CI: 55-100%) and 48% (95% CI: 11-85%). Causes of death were recurrent CNS disease (n = 7), herpes encephalitis (n = 1), and metastatic PNET outside the CNS (n = 1).

CONCLUSION

Hypofractionated SCRT provides effective local control with acceptable toxicity for patients with recurrent localized PNET. However, overall long-term disease control is rare and limited by the occurrence of CSF mediated relapses, which thus could benefit from intensive systemic chemotherapy as part of the primary relapse strategy even in local recurrences. Larger multi-national studies will be necessary to assess the value of such combined treatment approaches.

[The possibilities of fractionated external beam repeat irradiation of relapsed primary brain tumours: the first Hungarian experience]

INTRODUCTION

The practice of image-based three dimensional treatment planning and conformal radiotherapy techniques offer the opportunity to elaborate novel treatment forms, e.g. repeat irradiation techniques for primary brain tumours.

AIM

The authors analysed the effect on survival and toxicity of fractionated external beam repeat irradiation in brain tumour patients.

METHODS

At the National Institute of Oncology, between 2002 and 2006, fractionated external beam repeat irradiation was performed in eleven patients with recurrent primary brain tumour, with total of 50-54 Gy or near total of 34-40 Gy doses. All patients were previously treated with total radiotherapy doses of 50-64 Gy. The intervals between radiotherapy courses were in the range of 7-30 years. All the treatments were carried out with 3D image-based conformal methods, the fractionation was conventional, with 1,8-2,0 Gy daily fractions in all cases.

RESULTS

The repeat irradiation was tolerated well in the material. No grade 3-4 acute toxicity was detected, and serious, grade 3 mental deterioration, not related tumour progression was observed in only one case. In one case reoperation was necessary due to histologically verified radio-necrosis with mass-effect, and we believe that late neurotoxicity caused serious functional inabilities in one case. The median progression free survival was 8 (2-33) months, the median survival was 13 (4,5-33) months. Three of our patients were alive at the end of the study.

CONCLUSIONS

Based on this experience and current knowledge, in absence of other treatment possibilities, the fractionated external beam repeat irradiation with near total doses could be a therapeutic choice in case of recurrent primary brain tumours, if having appropriate background. To define the optimal treatment strategy and regimens, further clinical trials should be carried out.

Gamma knife radiosurgery for cavernous sinus metastases and invasion

BACKGROUND

We evaluated the efficacy of gamma knife radiosurgery for cavernous sinus metastases and invasion.

METHOD

We treated and followed up 21 patients with cavernous sinus metastases and invasion using gamma knife radiosurgery. Nine of these patients had nasopharyngeal cancer, and 12 had distant metastases from other cancers. The volume of tumors ranged from 2.9 to 50.0 (median 9.9) mL. and the radiation dose to the tumor margin was 10 to 21 (median 14) Gy.

RESULTS

The median follow-up period was 9 months. Clinical symptoms were improved in 48% of the patients after treatment, and tumor growth control was obtained in 67% of the patients at their final follow-up. The actual 1- and 2-year tumor growth control rates were 68% and 43%, respectively. The mean survival time was 13 months. No patient had radiation injury.

CONCLUSION

Gamma knife radiosurgery is a very useful therapeutic option for the treatment of cavernous sinus metastases and invasion, either as initial treatment or as an adjunct treatment for recurrences even in preirradiated patients.

Stereotactic radiosurgery for patients with cancer of the head and neck

Patients with recurrent cancer of the head and neck involving the base of the skull have limited treatment options. Stereotactic radiosurgery is currently being investigated as a viable modality of treatment for these patients. This paper reviews the basic principles and treatment procedures involved in stereotactic radiosurgery, as well as published reports on its use with these patients. Finally, questions to be addressed by future studies for clarification of the role of this technology are outlined.

Results of three-dimensional stereotactically-guided radiotherapy in recurrent medulloblastoma

PURPOSE

To evaluate survival rates and side effects after stereotactically-guided radiotherapy (SRT) in patients with recurrent medulloblastoma of the brain.

METHODS AND MATERIALS

Between 1992 and 2000, 20 patients with 29 radiological manifestations were treated with fractionated SRT (n = 21) or radiosurgery (n = 8). Median age was 16 years with 6 patients < or = 14 years. All patients had prior cranio-spinal radiotherapy plus boost to the posterior fossa with a total dose of 54 Gy. Time to recurrence was 33 months mean. Eighteen of the 29 lesions were located within the boost volume. Chemotherapy was given according to current international study protocols (HIT) in all patients. Mean total dose for re-irradiation was 24 Gy for fractionated stereotactically-guided radiotherapy, and 15 Gy for radiosurgery. Mean follow-up was 88.5 months.

RESULTS

Overall local control was 89.7%. Thirteen recurrences showed partial or complete response in CT/MR-imaging, 13 showed stable disease. Local tumor progression was seen 5 months mean after radiotherapy in three cases. A multifocal intracranial progression was seen in 9 patients, 5 patients developed additional spinal metastases. Thirteen patients died with disseminated cranio-spinal progression, after 72.6 months median. No late toxicity > CTC II(o) especially no brain radionecrosis was seen after radiotherapy.

CONCLUSION

SRT is effective and safe in the treatment of recurrent medulloblastoma to improve local control without evident side effects. The main problem remains the control of subclinical cranio-spinal dissemination.

Recent Advances in Radiotherapy for Head and Neck Cancers

Advancements in surgery have made it possible to resect cancers that had previously been regarded as incurable. Similarly, new developments in radiation oncology have helped improve the outlook for patients with locally advanced or recurrent head and neck cancers. Among these advancements are refinements in altered fractionation, three-dimensional conformal radiotherapy, intensity-modulated radiotherapy, stereotactic radiosurgery and fractionated stereotactic radiotherapy, neutron-beam radiotherapy, charged-particle radiotherapy, and intraoperative radiotherapy. These recent developments have allowed radiation oncologists to escalate the dose of radiation delivered to tumors while minimizing the dose delivered to surrounding normal tissue. Additionally, more continues to be learned about the optimum delivery of chemotherapy. This article provides an update on the status of these new developments in the treatment of head and neck cancers.

Fractionated stereotactic radiotherapy of small intracranial malignancies

PURPOSE

To retrospectively evaluate the effectiveness of fractionated stereotactic radiotherapy (FSRT) in patients with small intracranial malignancies.

METHODS AND MATERIALS

From July 1991 to March 1997, 80 patients with a total of 121 brain or skull-base tumors were treated with FSRT alone, and were followed for periods ranging from 3 to 62 months (median 9.8). The majority of patients received 42 Gy in 7 fractions over 2.3 weeks, but in July 1993, protocols using smaller fraction doses were introduced for patients whose radiation-field diameters were larger than 3 cm or whose tumors were close to critical normal tissues.

RESULTS

For 64 patients with metastatic brain tumors the overall median survival was 8.3 months and 1-year actuarial survival rate was 33%. Significant prognostic factors were: the presence of extracranial tumors, pre-treatment performance status, and the lung as a primary site. Patients without extracranial tumors prior to FSRT had a median survival of 21.2 months. For seven patients with high-grade glioma, 1-year actuarial local control rate was 75%, with a median survival of 10.3 months. For patients with skull-base tumors the local control was achieved in 6 of 6 patients (100%), with a median survival of 30.7 months. No one suffered from acute complications, but three patients, two of whom had undergone FSRT as the third course of radiotherapy, developed late radiation injuries.

CONCLUSION

Overall high local control and low morbidity rates suggest that FSRT is an effective and safe modality, even for those with a history of prior irradiation. However, patients with risk factors should be treated with smaller fraction doses.