CT Derived Hounsfield Unit: An Easy Way to Determine Osteoporosis and Radiation Related Fracture Risk in Irradiated Patients.

Background: We aimed to evaluate osteoporosis, bone mineral density, and fracture risk in irradiated patients by computerized tomography derived Hounsfield Units (HUs) calculated from radiation treatment planning system. Methods: Fifty-seven patients operated for gastric adenocarcinoma who received adjuvant abdominal radiotherapy were included in the study group. Thirty-four patients who were not irradiated after surgery comprised the control group. HUs of T12, L1, L2 vertebral bodies were measured from the computerized tomographies imported to the treatment planning system for all the patients. While the measurements were obtained just after surgery and 1 year later after surgery in the control group, the same measurements were obtained just before irradiation and 1 year after radiotherapy in the study group. Percent change in HU values (Δ%HU) was determined for each group. Vertebral compression fractures, which are the consequence of radiation induced osteoporosis and bone toxicity were assessed during follow-up. Results: There was no statistical significant difference in HU values measured for all the vertebrae between the study and the control group at the onset of the study. While HU values decreased significantly in the study group, there was no significant reduction in HU values in the control group after 1 year. significant correlation was found between Δ%HU and the radiation dose received by each vertebra. Insufficiency fractures (IFs) were observed only in the irradiated patients (4 out of 57 patients) with the cumulative incidence of 7%. Conclusions: HU values are very valuable in determining bone mineral density and fracture risk. Radiation treatment planning system can be utilized to determine HU values. IFs are common after abdominal radiotherapy in patients with low vertebral HU values detected during radiation treatment planning. Radiation dose to the vertebral bones with low HU values should be limited below 20 Gy to prevent late radiation related bone toxicity.

Is stereotactic body radiotherapy an alternative to surgery in early stage non small cell lung cancer?

PURPOSE: To determine local control and overall survival of patients with medically inoperable early-stage non-small cell lung cancer (NSCLC) treated with stereotactic ablative radiotherapy. METHODS: Included were a total of 52 patients (7;13% females and 45;87% males) with medically inoperable early-stage NSCLC and who were treated with stereotactic ablative body radiotherapy (SBRT) by a CyberKnife robotic radiotherapy machine between 2009 and 2017. Depending on tumor size and location, median 45 Gy (30-60) were delivered in median 3 fractions (3-5) to Planning Target Volume. As regards the tumor-tracking system; X-Sight lung tracking system was used in 43 (83%) patients, gold fiducials in 4 (8%) patients, and X-Sight spine tracking system in 5 (9%) patients. RESULTS: The median age of patients was 67 years (54-86). Tumor was staged as cT1 in 38 (73%) patients and cT2 in 14 (27%) patients. Median follow up was found to be 23 months (10-84 months). Median survival time was 38 months and, 1-3-5 year survival rates were respectively 94%-53%-33.6%. Locoregional recurrence occurred in 8 (15%) patients and recurrence was local only in 4 (8%) patients, while it was regional only in 3 (6%) and distant only in 12 (23%) patients. During follow up, local, regional and distant recurrence was detected in 27 (52%) cases and median progression free survival was found to be 25 months. 1-3-5 year progression free survival was 71.2%-39%-26%, respectively. Grade 3 toxicity was observed in only one patient; no grade 4-5 toxicity was observed. CONCLUSION: A high local control rate with no major toxicity was obtained by SBRT in the patients with medically inoperable early-stage NSCLC. In the near future, SBRT may be an alternative that has growing evidence to support comparable outcomes in selected stage I patients.

Pretreatment SUVmax value to predict outcome in patients with stage III NSCLC receiving concurrent chemoradiotherapy.

OBJECTIVE: Stage III disease accounts for approximately one-fourth of all non-metastatic non-small cell lung cancer (NSCLC). The patients who are not candidates for curative resection are offered concomitant chemoradiotherapy. In this subgroup, which is difficult to manage, studies that address the role of PET-CT to predict outcome measures specifically for stage III NSCLC receiving concurrent chemoradiotherapy may help better risk stratification. This study aimed to assess whether baseline PET maximum standardized uptake value (SUVmax) value in stage III NSCLC treated with concurrent chemoradiotherapy would independently identify patients with high risk of progression and death. METHODS: The study population consisted of patients aged 18 years or more with unresectable stage III histologically or cytologically proven NSCLC who received concurrent chemoradiotherapy. From 2007 to 2014, medical records of patients admitted to our institution were retrospectively analyzed. Pretreatment PET-CT SUVmax values were recorded for each patient. These values were categorized as low or high according to the median SUVmax measure of the study population. RESULTS: A total of 175 patients were analyzed. The median follow-up time was 23 months (range 6-109). The PET-CT SUVmax values ranged from 3.5 to 46 with a median value of 14. The median overall survival was 25 months in SUVmax <14 and 18 months in SUVmax ≥14 group (p=0.023). The median progression-free survival was 16 months in SUVmax <14 and 11 months in SUVmax ≥14 group (p=0.033). Multivariate analysis revealed that both PET-CT SUVmax value (p<0.001) and age (p=0.016) were independent significant predictors for overall survival (OS). CONCLUSION: The results of this study involving patients with stage III NSCLC receiving concurrent chemoradiotherapy provide evidence that suggests that high values of pretreatment SUVmax, an indicator of metabolic tumor burden, predicted a higher risk of disease progression and death.

Volumetric decrease of pancreas after abdominal irradiation, it is time to consider pancreas as an organ at risk for radiotherapy planning.

BACKGROUND: Volumetric shrinkage of normal tissues such as salivary glands, kidneys, hippocampus are observed after radiotherapy. We aimed to assess the alterations in pancreatic volume of patients who received abdominal radiotherapy and define pancreas as an organ at risk for radiation treatment planning. MATERIAL-METHODS: Forty-nine patients operated for gastric adenocarcinoma who received adjuvant abdominal radiotherapy were in the study group, 27 patients with early stage disease who did not need adjuvant treatment after surgery comprised the control group. An experienced radiologist contoured the pancreas of all the patients from computed tomographies imported to the planning system obtained either for radiation planning purpose or for follow-up after surgery. The same procedure was repeated one year later for both groups. Measured volume of the pancreas was expressed in cm3. RESULTS: Mean pancreatic volumes were similar in both groups at the onset of the study, 51,34 ± 20,33 cm3, and 50,12 ± 23,75 cm3 in the irradiated and the control groups respectively (p = 0,63). One year later, mean pancreatic volumes were significantly decreased in each group; 22,48 ± 10,53 cm3, 44,18 ± 23,08 cm3 respectively, p < 0,001. However, the decrease in pancreatic volume was significantly more pronounced in the irradiated group in comparison to the control group, p < 0,001. CONCLUSION: Volumetric decrease in normal tissues after radiotherapy is responsible for loss of organ function and radiation related late side effects. Although pancreas is a radiation sensitive organ losing its volume and function after radiation exposure, it is not yet considered as an organ at risk for radiation treatment planning. Pancreas should be contoured as an organ at risk, dose-volume histogram for the organ should be created, and safe organ doses should be determined. This is the first study declaring pancreas as an organ at risk for radiation toxicity and the necessity of defining dose constraints for the organ.

Osteoporosis development and vertebral fractures after abdominal irradiation in patients with gastric cancer.

BACKGROUND: Decrease in bone mineral density, osteoporosis development, bone toxicity and resulting insufficiency fractures as late effect of radiotherapy are not well known. Osteoporosis development related to radiotherapy has not been investigated properly and insufficiency fractures are rarely reported for vertebral bones. METHODS: Ninety-seven patients with gastric adenocarcinoma were evaluated for adjuvant treatment after surgery. While 73 out of 97 patients treated with adjuvant chemoradiotherapy comprised the study group, 24 out of 97 patients with early stage disease without need of adjuvant treatment comprised the control group. Bone mineral densities (BMD) of lumbar spine and femoral neck were measured by dual energy x-ray absorptiometry after surgery, and one year later in both groups. RESULTS: There was statistically significant decline in BMDs after one year in each group itself, however the decline in BMDs of the patients in the irradiated group was more pronounced when compared with the patients in the control group; p values were 0.02 for the decline in BMDs of lumbar spine, and 0.01 for femoral neck respectively. Insufficiency fractures were observed only in the irradiated patients (7 out of 73 patients) with a cumulative incidence of 9.6%. CONCLUSIONS: Abdominal irradiation as in the adjuvant treatment of gastric cancer results in decrease in BMD and osteoporosis. Insufficiency fracture risk in the radiation exposed vertabral bones is increased. Calcium and vitamin D replacement and other measures for prevention of osteoporosis and insufficiency fractures should be considered after abdominal irradiation.

Fractionated stereotactic radiosurgery for vestibular schwannomas using cyberknife: A single institution experience.

OBJECTIVE: To assess tumour control, hearing preservation status, and complication ratio after fractionated stereotactic radiosurgery/radiotherapy by using CyberKnife device in patients with vestibular schwannomas. METHODS: This retrospective study was conducted at Izmir Ataturk Research and Tranining Hospital, Turkey, and comprised data of vestibular schwannomas patients treated with stereotactic radiosurgery/radiotherapy from March 2010 to December 2013. The patients were subjected to a dose ranging from 12 to 30Gy using CyberKnife system with an average of three fractions. SPSS 17 was used for data analysis. Paired t-test and Pearson's chi-square test were used to compare clinical parameters between groups. P<0.05 was considered significant. RESULTS: Of the 41 patients, 26(63.4%) were women and 15(36.6%) were men. The median follow-up duration after stereotactic radiosurgery/radiotherapy was 25 months (interquartile range: 9-44 months). Radiographic control evaluation ratio was 95.7% with a median follow-up of 3 years (IQR: 18.5 months). Results of 23(56%) patients showed stabile response, 17(42%) regression response and 1(2%) progression response. There were no statistically significant changes between pre- and post-stereotactic radiosurgery/radiotherapy symptoms (p>0.05). One (2.4%) patient reported new onset facial paresis. CONCLUSIONS: Stereotactic radiosurgery/radiotherapy treatment of vestibular schwannomas resulted in a good ratio of tumour control. Hearing preservation status and ratios of toxicity were comparable to published literature.

The clinicopathological evaluation of the breast cancer patients with brain metastases: predictors of survival.

We aimed to define the clinicopathologic characteristics of breast cancer (BC) patients with brain metastasis (BM) and to investigate the effect of these parameters on survival. Seventy-nine patients diagnosed with BC and symptomatic BM between 1995 and 2011 were retrospectively evaluated. The relationship between clinicopathological features and outcome was investigated. Triple negative patients had the shortest overall survival (OS) while HR(+)HER2(-) patients had the longest (48.2  vs 88.2 months, 95 % CI; p = 0.33). Multivariate analysis demonstrated that luminal A subtype was the strongest positive predictor of prolonged OS (HR 0.48, 95 % CI 0.28-0.84; p = 0.01), while poor performance status (PS) (ECOG 3-4) at BM was the strongest predictor of shortened OS (HR 1.92, 95 % CI 1.21-3.06; p = 0.006). The patients with early-stage BC at diagnosis had BM later than the advanced-staged patients (47 months for Stage I-II disease, 23.2 months for Stage III-IV disease, 95 % CI; p = 0.002). Median survival after BM was 10.2 months (6.4-14 months, 95 % CI). The patients with liver or skin metastases had significantly shorter survival than the patients with only BM (4.8 vs 17 months, p < 0.001 for liver and 4.8 vs 11.1 months, p = 0.04 for skin). Multivariate analysis demonstrated that regardless of the BC subtype, lack of systemic therapy, and liver involvement were independent factors associated with increased risk of death (HR 4, 95 % CI 1.7-9.1; p = 0.001 and HR 2.2, 95 % CI 1.05-4.9; p = 0.036 respectively). Clinical outcome after BM mostly depends on the ECOG PS and the fact that whether the patient received systemic therapy or not. Systemic therapy prolongs survival especially in HER2 positive patients.