Outcomes of accelerated hypofractionated radiotherapy in stage i non-small-cell lung cancer

PURPOSE

Outcomes after treatment with accelerated hypofractionated radiotherapy in stage i medically inoperable non-small-cell lung cancer (nsclc) patients were determined.

METHODS

Our single-institution retrospective review looked at medically inoperable patients with T1-2N0M0 nsclc treated with accelerated hypofractionated curative-intent radiotherapy between 1999 and 2009. Patients were staged mainly by computed tomography imaging of chest and abdomen, bone scan, and computed tomography/magnetic resonance imaging of brain. Positron-emission tomography (pet) staging was performed in 6 patients. Medical charts were reviewed to determine demographics, radiotherapy details, sites of failure, toxicity (as defined by the Common Terminology Criteria for Adverse Events, version 3.0) and vital status. The cumulative incidence of local and distant failure was calculated. Overall (os) and cause-specific (css) survival were estimated by the Kaplan-Meier method.

RESULT

In the 60 patients treated during the study period, the dose regimens were 50 Gy in 20 fractions (n = 6), 55 Gy in 20 fractions (n = 8), 60 Gy in 20 fractions (n = 42), and 60 Gy in 25 fractions (n = 4). All patients were treated once daily. The median follow-up was 27 months (range: 4-94 months). The os rates at 2 and 5 years were 61% [95% confidence interval (ci): 50% to 75%] and 19% (95% ci: 10% to 34%) respectively. The css rates at 2 and 5 years were 79% (95% ci: 68% to 91%) and 39% (95% ci: 24% to 63%) respectively. The cumulative incidence of local failure was 20% at 5 years. The cumulative incidence of distant failure was 28% at 5 years. No patients experienced grade 3 or greater pneumonitis or esophagitis.

CONCLUSIONS

Accelerated hypofractionated regimens are well tolerated and provide good local control in medically inoperable patients with stage i nsclc. Such regimens may be a reasonable treatment alternative when stereotactic body radiation therapy is not feasible.

Poster - Thur Eve - 20: Serial FDG 4DPET imaging during radiotherapy in advanced lung cancer patients

The availability of respiratory synchronized PET (4DPET) imaging has enabled more accurate analysis of metabolic response since motion blur is minimized. We present our preliminary analysis of serial FDG 4DPET images acquired at weeks 0, 2, 4, and 7 during radiotherapy of seven stage II-III NSCLC patients. The tumor and nodal PTV of the week 0 images restrained a 4DPET image thresholding algorithm to automatically contour SUV levels ranging from 20 to 80% of the maximum SUV, creating an intensity volume histogram (IVH) for each week. These contours allowed analysis of PET volumes and standard PET metrics such as SUV_max and SUV_mean . We found a trend for decreasing SUV_max and SUV_mean over a treatment course in both the tumor and nodal regions. On average, the SUV_max within the tumor decreased by 17±13% (1 SD) after 2 weeks, 30±13% after 4 weeks, and 39±19% after 7 weeks of radiotherapy. Decreasing volume trends were also observed in the 20 to 80% max SUV autocontours, ranging from 26±29% to 50±40% respectively, over 7 weeks of treatment. Only one patient demonstrated an increase in FDG uptake within the tumor volume between week 0 and week 2 of treatment, and was also the only patient to recur locally at 3 months following treatment. Changes in tumor metabolism over the course of advanced NSCLC radiotherapy are quantifiable with serial FDG 4DPET imaging. Preliminary analysis suggests that variations in these trends could be useful in identifying non-responding patients that may require an alternative radiotherapeutic approach.

Transgastric endoscopic gastroenterostomy using a partially covered occluder: a canine feasibility study

BACKGROUND AND STUDY AIMS

The use of natural orifice transluminal endoscopic surgery (NOTES) for gastroenterostomy has been previously reported, but it remains technically challenging and additional assistance is often needed. The aim of this study was to develop and evaluate a novel method for the creation of a gastroenterostomy using NOTES with an occluder.

METHODS

Transgastric endoscopic gastroenterostomy was performed in 12 healthy female dogs using a therapeutic upper gastrointestinal endoscope and a partially covered occluder. The occluder was removed with a snare 1 week later. The patency of the gastroenterostomy was confirmed by endoscopy, contrast radiological study, necropsy, and histological examination after 2 weeks.

RESULTS

NOTES gastroenterostomy with an occluder was successful in all 12 dogs. The mean operative time was 32.3 ± 10.3 min (range 20.3 - 53.5). One dog (the first; 8.3 %) died 4 days after the operation of severe intra-abdominal infection due to incorrect deployment of the occluder and poor bowel preparation. Minor bleeding occurred at the anastomosis after removal of the occluder in two of the remaining dogs (18.2 %). Necropsy revealed postoperative adhesions that had developed at the anastomotic site in one dog (9.1 %). No anastomotic leakage or intestinal obstruction was observed. Complete healing of the anastomosis was confirmed on histological evaluation.

CONCLUSION

Gastroenterostomy performed entirely by NOTES using an occluder was technically feasible in this survival animal model.

The impact of prior radiotherapy on fatal complications after self-expandable metallic stents (SEMS) for malignant dysphagia due to esophageal carcinoma

The esophageal stent has been demonstrated to serve as a safe and effective palliative treatment for advanced inoperable esophageal carcinoma. However, the safety of esophageal stents in patients with prior radiotherapy (RT) remains debated. This article aims to investigate the impact of prior RT on the incidence of fatal complications after self-expandable metallic stents for palliation of malignant dysphagia because of esophageal carcinoma. Between January 2007 and July 2010, 93 patients with malignant dysphagia because of esophageal carcinoma underwent placement of self-expandable metallic stents in our hospital. Patients were retrospectively separated into two groups: patients with RT before stent placement (RT group, n=57) and patients with no treatment before stent placement (no RT group, n=35).The median survival after stent placement was 77 days (7-842 days) in the RT group and 246 days (15-878 days) in the no RT group. Improvement in dysphagia score was similar in both groups. The fatal complications included fatal gastrointestinal hemorrhage and uncontrolled pneumonia. The incidence of fatal gastrointestinal hemorrhage and uncontrolled pneumonia were 28.1% and 5.7% (P=0.009), 28.1% and 5.7% (P=0.009), respectively. Logistic regression analysis showed a significant interaction between prior RT and fatal gastrointestinal hemorrhage (relative risk 7.82, 95% confidence interval 1.54-39.61; P=0.013). Mortality of massive hemorrhage was 5.7% (2/35), 0% (0/4), 12.5% (3/24), and 44.8% (13/29), respectively, in patients who received 0, 1Gy∼49Gy, 50Gy∼60Gy, and >60Gy (χ(2) =17.761; P=0.000). Logistic regression analysis disclosed prior RT did not significantly increase the risk of uncontrolled pneumonia (relative risk 1.47, 95% confidence interval 0.21-10.12; P=0.697).

Telocytes in trachea and lungs

We show the existence of a novel type of interstitial cell-telocytes (TC) in mouse trachea and lungs. We used cell cultures, vital stainings, as well as scanning electron microscopy (SEM), transmission electron microscopy (TEM) and immunohistochemistry (IHC). Phase contrast microscopy on cultured cells showed cells with unequivocally characteristic morphology of typical TC (cells with telopodes-Tp). SEM revealed typical TC with two to three Tp-very long and branched cell prolongations. Tp consist of an alternation of thin segments (podomers) and thick segments (podoms). The latter accommodate mitochondria (as shown by Janus Green and MitoTracker), rough endoplasmic reticulum and caveolae. TEM showed characteristic podomers and podoms as well as close relationships with nerve endings and blood capillaries. IHC revealed positive expression of TC for c-kit, vimentin and CD34. In conclusion, this study shows the presence in trachea and lungs of a peculiar type of cells, which fulfils the criteria for TC.