Hakan Gamsiz

Management of patients with recurrent glioblastoma using hypofractionated stereotactic radiotherapy.

Background Glioblastoma (GBM) is the most common primary malignant brain tumor in adults. The chance of cure is very limited due to treatment-refractory disease course with frequent recurrences despite aggressive multimodality management. In this retrospective study, we evaluated treatment outcomes of hypofractionated stereotactic radiotherapy (HFSRT) in the management of recurrent GBM and report our single-center experience. Methods Twenty-eight patients receiving HFSRT for recurrent GBM between September 2008 and February 2014 were retrospectively assessed. Total radiotherapy dose was 25 Gy delivered in 5 fractions over 5 consecutive days for all patients. High-precision, image-guided volumetric modulated arc therapy was delivered with a linear accelerator using 6-MV photons using the frameless technique. Analyzed prognostic factors were age, gender, Karnofsky performance status (KPS), tumor location, planning target volume (PTV) size, overall survival (OS), progression-free survival (PFS), time interval between completion of treatment with Stupp protocol at primary diagnosis and recurrence. Results Median follow-up time was 42 months (range 2–68). Median time interval between primary chemoradiotherapy and HFSRT was 11.2 months (range 4–57.9). Median OS and PFS calculated from reirradiation was 10.3 months and 5.8 months, respectively. Longer interval between initial treatment and recurrence (p = 0.01), smaller PTV size (p = 0.001), KPS ≥70 (p = 0.005) and younger age (p = 0.004) were associated with longer OS on statistical analysis. Conclusion HFSRT offers a feasible and effective salvage treatment option for recurrent GBM management. Prognostic factors associated with longer OS in our study were longer interval between initial treatment and recurrence, smaller PTV size, KPS ≥70 and younger age.

Evaluation of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) for cerebral cavernous malformations: a 15-year single-center experience.

BACKGROUND AND OBJECTIVES Surgery is the principal treatment for safely accessible hemorrhagic and symptomatic cavernous malformations. Nevertheless, the role of linear accelerator (LINAC)-based stereotactic radiosurgery (SRS) in the management of high-risk, symptomatic cavernoma lesions warrants further refinement. In this study, we evaluate the use of LINAC-based SRS for cerebral cavernous malformations (CMs) and report our 15-year single-center experience. DESIGN AND SETTINGS A retrospective study from the Department of Radiation Oncology and the Department of Neurosurgery at Gulhane Military Medical Academy and Medical Faculty, Ankara from April 1998 to June 2013. PATIENTS AND METHODS Fifty-two patients (22 females and 30 males) with cerebral CM referred to our department underwent high-precision single-dose SRS using a LINAC with 6-MV photons. All patients had at least 1 bleeding episode prior to radiosurgery along with related symptoms. Median dose prescribed to the 85% to 95% isodose line encompassing the target volume was 15 Gy (range, 10–20). RESULTS Out of the total 52 patients, follow-up data were available for 47 patients (90.4%). Median age was 35 years (range, 19–63). Median follow-up time was 5.17 years (range, 0.08–9.5) after SRS. Three hemorrhages were identified in the post-SRS period. Statistically significant decrease was observed in the annual hemorrhage rate after radiosurgical treatment (pre-SRS 39% vs post-SRS 1.21, P<.0001). Overall, there were no radiosurgery-related complications resulting in mortality. CONCLUSION LINAC-based SRS may be considered as a treatment option for high-risk, symptomatic cerebral CM of selected patients with prior bleeding from lesions located at surgically inaccessible or eloquent brain areas.

Evaluation of stereotactic body radiation therapy in the management of adrenal metastases from non-small cell lung cancer.

Aims and Background In this retrospective analysis, we evaluated the use of stereotactic body radiation therapy in the management of adrenal metastases from non-small cell lung cancer and report our single center experience. Methods and Study design Fifteen non-small cell lung cancer patients (9 male, 6 female) with 17 adrenal metastases referred to Gulhane Military Medical Academy Radiation Oncology Department were treated using active breathing control-guided stereotactic body radiation therapy between December 2009 and October 2013. Dose per fraction was 10 Gy to deliver a total dose of 30 Gy over 3 consecutive days for all metastatic adrenal lesions. The mean gross tumor volume was 28.4 cc (range 6.6-101.5) and mean planning target volume was 57.4 cc (range 16.5-143.8). Results At a median follow-up of 16 months, local control was 86.7% and overall survival was 33.3%. Median disease-free survival was 10 months. Treatment response according to RECIST was categorized as complete response in 3 patients (20%), partial response in 5 patients (33.3%), stable disease in 5 patients (33.3%), and progressive disease in 2 patients (13.3%). Most common acute toxicity was grade 1 nausea (n = 7) and grade 1 fatigue (n = 12). There was no case of grade ≥3 acute or late toxicity. Conclusions Stereotactic body radiation therapy offers a safe and efficacious management strategy for adrenal metastases from non-small cell lung cancer by providing excellent local control with negligible treatment related toxicity.

Management of patients with ≥4 brain metastases using stereotactic radiosurgery boost after whole brain irradiation.

Aims and Background Brain metastases are a prevalent consequence of systemic cancer, and patients suffering from brain metastases usually present with multiple metastatic lesions. An overwhelming majority of the available literature assessing the role of stereotactic radiosurgery in brain metastasis management includes patients with up to 4 metastases. Given the significant benefit of stereotactic radiosurgery for the treatment of 1 to 3 brain metastases, we evaluated the use of stereotactic radiosurgery boost after whole brain irradiation in the management of patients with ≥4 brain metastases. Methods In this retrospective analysis, outcomes of 50 patients who underwent linear accelerator-based stereotactic radiosurgery boost within 4 to 6 weeks of whole brain irradiation for ≥4 brain metastases were assessed in terms of local control, overall survival, primary involved organ, recursive partitioning analysis class and Karnofsky performance status at the time of stereotactic radiosurgery, number of lesions, age, status of the primary cancer (controlled vs uncontrolled), presence of extracranial disease and toxicity. Results Fifty patients with ≥4 brain metastases were treated using linear accelerator-based stereotactic radiosurgery boost after whole brain irradiation between April 1998 and April 2013. Mean and median number of intracranial lesions was 6.02 and 6, respectively. Median lesion volume was 10.9 cc (range, 0.05–32.6). Median survival time after radiosurgery was 10.1 months (range, 1–25). Status of the primary cancer (controlled vs uncontrolled), recursive partitioning analysis class, Karnofsky performance status, and extracranial metastasis showed statistically significant correlations with overall survival (P <0.001). Treatment-related side effects after stereotactic radiosurgery included temporary edema (n = 14, 28%), hemiparesis (n = 1, 2%), seizure (n = 1, 2%), leukoencephalopathy (n = 2, 4%), and radiation necrosis (n = 6, 12%). Conclusions Linear accelerator-based stereotactic radiosurgery boost within 4 to 6 weeks after whole brain irradiation proved to be an efficacious and well-tolerated treatment strategy for the management of patients with ≥4 brain metastases in our study.

Evaluation of linear accelerator-based stereotactic radiosurgery in the management of glomus jugulare tumors.

AIMS AND BACKGROUND Although mostly benign and slow-growing, glomus jugulare tumors have a high propensity for local invasion of adjacent vascular structures, lower cranial nerves and the inner ear, which may result in substantial morbidity and even mortality. Treatment strategies for glomus jugulare tumors include surgery, preoperative embolization followed by surgical resection, conventionally fractionated external beam radiotherapy, radiosurgery in the form of stereotactic radiosurgery or fractionated stereotactic radiation therapy, and combinations of these modalities. In the present study, we evaluate the use of linear accelerator (LINAC)-based stereotactic radiosurgery in the management of glomus jugulare tumors and report our 15-year single center experience. METHODS AND STUDY DESIGN Between May 1998 and May 2013, 21 patients (15 females, 6 males) with glomus jugulare tumors were treated using LINAC-based stereotactic radiosurgery at the Department of Radiation Oncology, Gulhane Military Medical Academy. The indication for stereotactic radiosurgery was the presence of residual or recurrent tumor after surgery for 5 patients, whereas 16 patients having growing tumors with symptoms received stereotactic radiosurgery as the primary treatment. RESULTS Median follow-up was 49 months (range, 3-98). Median age was 55 years (range, 24-77). Of the 21 lesions treated, 13 (61.9%) were left-sided and 8 (38.1%) were right-sided. Median dose was 15 Gy (range, 10-20) prescribed to the 85%-100% isodose line encompassing the target volume. Local control defined as either tumor shrinkage or the absence of tumor growth on periodical follow-up neuroimaging was 100%. CONCLUSIONS LINAC-based stereotactic radiosurgery offers a safe and efficacious management strategy for glomus jugulare tumors by providing excellent tumor growth control with few complications.

Dosimetric evaluation of critical organs at risk in mastectomized left-sided breast cancer radiotherapy using breath-hold technique

AIMS AND BACKGROUND The aim of the study was to evaluate the dosimetric impact of the active breathing control-moderate deep inspiration breath-hold (ABC-mDIBH) technique on normal tissue sparing in locally advanced left-sided breast cancer radiotherapy. METHODS AND STUDY DESIGN Twenty-seven consecutive patients with left-sided locally advanced breast cancer referred to our department for adjuvant radiotherapy were enrolled in the study. Each patient was scanned at free breathing and ABC-mDIBH for radiation treatment planning. Two separate radiotherapy treatment plans were generated with and without ABC-mDIBH to investigate the dosimetric impact of ABC-mDIBH in breast cancer radiotherapy. RESULTS Between June 2011 and February 2012, 27 consecutive patients with left-sided locally advanced breast cancer referred to our department for adjuvant radiotherapy were enrolled in the study. Dose-volume parameters of left anterior descending coronary artery, lungs, heart, contralateral breast, esophagus and spinal cord were significantly reduced with the use of ABC-mDIBH (P <0.001). CONCLUSIONS Our study revealed that the use of ABC-mDIBH in the practice of locally advanced mastectomized left-sided breast cancer radiotherapy improves normal tissue sparing with the expected potential of decreasing treatment-related morbidity and mortality. Moreover, the resultant reduction achieved with ABC in doses to the left anterior descending coronary artery, which plays a central role in cardiac perfusion, may have implications for decreasing the potential of radiation-induced cardiac morbidity and mortality.

Adaptive splenic radiotherapy for symptomatic splenomegaly management in myeloproliferative disorders.

Aims and Background Symptomatic, massive splenomegaly is a debilitating complication of myeloproliferative disorders. In the study, we evaluated the use of a contemporary, individualized radiotherapeutic approach for splenic irradiation, including 3-dimensional computed tomography-based treatment planning, individualized treatment margins based on splenic motion assessment, online setup verification with volumetric image guidance at each fraction, and adaptive radiation treatment planning to account for changes in splenic size during the fractionated radiotherapy course. Methods and Study design Between December 2008 and January 2014, 18 patients (13 males, 5 females) with myeloproliferative disorders referred to Gulhane Military Medical Academy Radiation Oncology Department underwent 22 courses of splenic irradiation using 3-dimensional computed tomography-based treatment planning and volumetric image guidance for palliation of symptomatic splenomegaly. Results Median age was 64 years (range 28-79). Significant pain relief was achieved in 20 of the 22 splenic irradiation courses (90.9%). Improvement in hematological parameters was achieved in 8 of the 11 splenic irradiation courses applied for cytopenia (72.7%). At least a 50% reduction in splenic size was achieved in 18 of the 22 splenic irradiation courses (81.8%). Toxicity was manageable with supportive treatment including antiemetics and platelet or red blood cell transfusions. Conclusions Splenic irradiation with a contemporary radiotherapeutic approach offers safe and effective palliation of symptomatic splenomegaly in myeloproliferative disorders.

Management of vestibular schwannomas with linear accelerator-based stereotactic radiosurgery: a single center experience.

AIMS AND BACKGROUND The primary goal of treatment for vestibular schwannoma is to achieve local control without comprimising regional cranial nerve function. Stereotactic radiosurgery has emerged as a viable therapeutic option for vestibular schwannoma. The aim of the study is to report our 15-year single center experience using linear accelerator-based stereotactic radiosurgery in the management of patients with vestibular schwannoma. METHODS AND STUDY DESIGN Between July 1998 and January 2013, 68 patients with unilateral vestibular schwannoma were treated using stereotactic radiosurgery at the Department of Radiation Oncology, Gulhane Military Medical Academy. All patients underwent high-precision stereotactic radiosurgery using a linear accelerator with 6-MV photons. RESULTS Median follow-up time was 51 months (range, 9-107). Median age was 45 years (range, 20-77). Median dose was 12 Gy (range, 10-13) prescribed to the 85%-95% isodose line encompassing the target volume. Local tumor control in patients with periodic follow-up imaging was 96.1%. Overall hearing preservation rate was 76.5%. CONCLUSIONS Linear accelerator-based stereotactic radiosurgery offers a safe and effective treatment for patients with vestibular schwannoma by providing high local control rates along with improved quality of life through well-preserved hearing function.

Management of pulmonary oligometastases by stereotactic body radiotherapy.

AIMS AND BACKGROUND The aim of the study was to evaluate the feasibility, toxicity and effectiveness of active breathing control-guided stereotactic body radiotherapy in the management of pulmonary oligometastases. METHODS AND STUDY DESIGN Between June 2010 and June 2012, 20 patients (13 males, 7 females) with 31 pulmonary metastases referred to the Department of Radiation Oncology, Gulhane Military Medical Academy were treated using active breathing control-guided stereotactic body radiotherapy. Response Evaluation Criteria in Solid Tumors and Common Terminology Criteria for Adverse Events were used in the assessment of treatment response and toxicity, respectively. RESULTS Assessment of treatment response revealed complete response, partial response, stable disease, and progressive disease in 30%, 25%, 30%, and 15% of the patients, respectively. At a median follow-up of 14 months, local control was 85% and overall survival was 70%, with negligible treatment-related toxicity. CONCLUSIONS Stereotactic body radiotherapy is safe and effective in the management of pulmonary oligometastases. It offers favorable treatment outcomes as a viable non-invasive therapeutic modality.

Castleman's disease and radiotherapy: A single center experience

CONTEXT The role of radiotherapy (RT) in the management of Castlemans disease (CD) is analyzed. AIMS The main goal of this study is to examine the efficiency of RT in the treatment of unresectable and recurrent CD. SETTINGS AND DESIGN Retrospective study. SUBJECTS AND METHODS Between 1980 and 2012, 11 CD patients referred and treated at our clinic were studied. Three of the patients were female, and eight of them were male. Four patients had multicentric (MC) and seven patients had unicentric CD. Five patients were managed with incisional biopsy and RT; three unicentric patients underwent total excision followed by RT, and three unicentric patients had total excision and chemotherapy. Patients were retrospectively evaluated. Median follow-up time was 36 (24-60) months with median age 41 (24-52) years and RT dose 30 (30-45) Gy. STATISTICAL ANALYSIS USED Kaplan-Meier method. RESULTS About 72.7% of patients were male, and 27.3% were female. 63.6% of the patients were unicentric, and 36.4% were MC CD. 54.5% of the patients were managed with total excision, and 45.5% underwent incisional biopsy. About 63.6% of CD patients received RT and 27.3% were given only chemotherapy, whereas one patient (9.09%) received both RT and chemotherapy. Three-year survival was 83%, and 3-year disease free survival was 91%. No late toxicity was noted with. Acute toxicity was noted in two patients who received 45 Gy and no late radiation-induced toxicity was observed. CONCLUSIONS RT is an effective treatment option for CD recurrences and sole treatment for unresectable CD.