Exploring the variability of radiomic features of lung cancer lesions on unenhanced and contrast-enhanced chest CT imaging.

PURPOSE: The aim of this methods work is to explore the different behavior of radiomic features resulting by using or not the contrast medium in chest CT imaging of non-small cell lung cancer. METHODS: Chest CT scans, unenhanced and contrast-enhanced, of 17 patients were selected from images collected as part of the staging process. The major T1-T3 lesion was contoured through a semi-automatic approach. These lesions formed the lesion phantoms to study features behavior. The stability of 94 features of the 3D-Slicer package Radiomics was analyzed. Feature discrimination power was quantified by means of Gini's coefficient. Correlation between distance matrices was evaluated through Mantel statistic. Heatmap, cluster and silhouette plots were applied to find well-structured partitions of lesions. RESULTS: The Gini's coefficient evidenced a low discrimination power, <0.05, for four features and a large discrimination power, around 0.8, for five features. About 90% of features was affected by the contrast medium, masking tumor lesions variability; thirteen features only were found stable. On 8178 combinations of stable features, only one group of four features produced the same partition of lesions with the silhouette width greater than 0.51, both on unenhanced and contrast-enhanced images. CONCLUSIONS: Gini's coefficient highlighted the features discrimination power in both CT series. Many features were sensitive to the use of the contrast medium, masking the lesions intrinsic variability. Four stable features produced, on both series, the same partition of cancer lesions with reasonable structure; this may merit being objects of further validation studies and interpretative investigations.

Prostate cancer dose-response, fractionation sensitivity and repopulation parameters evaluation from 25 international radiotherapy outcome data sets.

OBJECTIVE: This study was undertaken to model the biochemical free survival at 5 years and to evaluate the parameters defining dose-response curve, dose-fractionation radiosensitivity and repopulation. METHODS: It was carried out a literature search on Pubmed to retrieve data sets of patients treated with external beam radiation therapy of 1.8-4.0 Gy per fraction and overall treatment time of 3 to 10 weeks. 10 groups were identified, based on risk class and androgen deprivation therapy (ADT). Dose-response curve D50 (dose at 50% probability of control) and g50 (steepness), α/ß (dose-fractionation radiosensitivity), and repopulation parameters, dprolif and Tprolif , were calculated. Bootstrap-based cross-validation was performed and median and 95% CI (confidence interval) were evaluated. RESULTS: 25 data sets, including 20,310 patients, were considered. The median (95% CI) D50 and g50 values were 62 (CI 53 - 66) Gy and 1.6 (0.8 - 2.4). ADT patients showed lower values of D50 and g50 (57 ± 5 Gy and 1.1 ± 0.4) compared to no-ADT patients (65 ± 2 Gy and 2.3 ± 0.6), with p < 0.0001 and p = 0.002. If we did not consider any dependence on overall treatment time, the median (95% CI) value of α/ß was 1.4 (1.0 - 1.9) Gy with p < 0.0001 for all patients. The median values of dproli f and Tprolif were 0.0 to 0.3 Gy/d and 18-40 days. CONCLUSION: Dose-response curve resulted dependent on risk class and ADT, with higher steepness for no-ADT patients. Low values of dose-fractionation radiosensitivity were found, supporting the use of moderate hypofractionated radiotherapy in each risk class. A limited dependence on repopulation was observed. ADVANCES IN KNOWLEDGE: Prostate cancer response to moderate hypofractionated radiotherapy was reliably quantified considering risk class and androgen deprivation therapy.

Usefulness of magnetic resonance in patients with invasive cancer eligible for breast conservation: a comparative study.

BACKGROUND: The role of magnetic resonance imaging (MRI) in newly detected breast cancer remains controversial. We investigated the impact of preoperative MRI on surgical management of infiltrating breast carcinoma (IBC). METHODS: We reviewed data of 237 patients with IBC who were suitable for breast-conserving surgery (BCS) between 2009 and 2011. Of these patients, 109 underwent preoperative MRI (46%; MRI group) and 128 did not (54%; no-MRI group). We analyzed MRI-triggered changes in surgical plan and compared differences in rates of positive margins and mastectomy. RESULTS: Tumor size was larger in the MRI group (16.8 mm vs. 13.9 mm; P < .001). MRI changed the initial surgical planning in 18 of 109 patients (16.5%) because of detection of larger tumor diameter requiring wider resection (8 patients [7.3%]) or additional malignant lesions in the ipsilateral (9 patients [8.2%]) or contralateral breast (1 patient [0.9%]). MRI-triggered treatment changes included mastectomy (n = 12), wider excision (n = 5), and contralateral BCS (n = 1). Reoperation rates for positive margins after BCS appeared higher in the no-MRI group (4.1% vs. 8.6%), but the difference missed statistical significance (P = .9). Overall mastectomy rates were higher in the MRI group (13.7% vs. 7.0%; P < .05). The likelihood of having a change of treatment resulting from MRI was significantly higher for patients with tumors > 15 mm and for those with positive lymph nodes. CONCLUSION: Lymph node positivity and tumor size > 15 mm may predict an MRI-triggered change in surgical plan. Preoperative MRI resulted in higher mastectomy rates justified by biopsy-proven additional foci of carcinoma and did not significantly reduce reoperation rates for positive margins.

Omental Well-Differentiated Liposarcoma: US, CT and MR Findings.

Liposarcomas are the most common of sarcoma tumours, they are usually located in the lower limbs, retroperitoneum, or abdominal cavity; up to date, only a few cases of omental liposarcoma with different histotype have been described. We present a case of omental well-differentiated liposarcoma and discuss imaging findings on ultrasound, computed tomography, and magnetic resonance to differentiate omental liposarcomas from other abdominal tumour entities.

Effective management of intrathoracic anastomotic leak with covered self-expandable metal stents. Report on three cases.

Intrathoracic anastomotic leakage is one of the major complications of esophageal surgery that can lead to high mortality rate. Depending on the clinical presentation, therapeutic options include surgical reintervention and conservative management with or without external drainage or stenting. In this paper, we report a series of three patients, two men and one woman, mean age of 55.6 years (range 34-68 years), having intrathoracic anastomotic leak after esophagogastrectomy treated by insertion of four covered self-expandable metal stents performed exclusively under fluoroscopic view. Complete resolution of the leakage was obtained in all patients. Despite the limited number of patients, conservative management of intrathoracic anastomotic leaks with covered self-expandable metal stents performed under fluoroscopic guidance has proved to be rapid, safe, and effective in all cases of this series.

Palliative airway stenting performed under radiological guidance and local anesthesia.

PURPOSE: To assess the effectiveness of airway stenting performed exclusively under radiological guidance for the palliation of malignant tracheobronchial strictures. METHODS: We report our experience in 16 patients with malignant tracheobronchial stricture treated by insertion of 20 Ultraflex self-expandable metal stents performed under fluoroscopic guidance only. Three patients presented dysphagia grade IV due to esophageal malignant infiltration; they therefore underwent combined airway and esophageal stenting. All the procedures were performed under conscious sedation in the radiological room; average procedure time was around 10 min, but the airway impediment never lasted more than 40 sec. RESULTS: We obtained an overall technical success in 16 cases (100%) and clinical success in 14 patients (88%). All prostheses were successfully placed without procedural complications. Rapid clinical improvement with symptom relief and normalization of respiratory function was obtained in 14 cases. Two patients died within 48 hr from causes unrelated to stent placement. Two cases (13%) of migration were observed; they were successfully treated with another stent. Tumor overgrowth developed in other 2 patients (13%); however, no further treatment was possible because of extensive laryngeal infiltration. CONCLUSIONS: Tracheobronchial recanalization with self-expandable metal stents is a safe and effective palliative treatment for malignant strictures. Airway stenting performed exclusively under fluoroscopic view was rapid and well tolerated.

Postoperative radiologic evaluation of the esophagus.

A wide range of surgical procedures are performed for either benign and malignant esophageal lesions, that may be classified as demolitive or conservative interventions. The former is characterized by resection and replacement of the esophagus with another organ, whereas conservative surgery is obtained preserving esophageal function without resection. Knowledge of surgical techniques and major complications is extremely important for a correctly performed radiographic study and a proper interpretation of the imaging findings. Functional evaluation of the operated alimentary tract and early detection of postoperative complications are essential for a successful recovery of esophageal surgery patients. We provide a brief overview of the main esophageal surgical procedures, reporting our experience on postoperative imaging of 104 patients submitted to surgery for either benign or malignant esophageal disease during a 6-year period.

Duodenal switch without gastric resection: results and observations after 6 years.

BACKGROUND: The results on metabolic effects of the classical biliopancreatic diversion (BPD) have led us to investigate the operation without gastric resection, thus preserving stomach and pylorus, in patients who are not seriously obese but suffer from hypercholesterolemia, often associated with type 2 diabetes and hypertriglyceridemia. METHODS: Between 1996 and 1999, we performed the duodenal switch (DS) without gastric resection on 24 mildly obese patients. Mean preoperative BMI was 36.2 kg/m(2). 17 patients (70.8%) suffered from type 1 diabetes, 4 (16.6%) had impaired glucose tolerance, while the remainder had fasting hyperglycemia. In 20 patients (83.3%), hypercholesterolemia and alterations in lipid profile were present. Another 20 patients were taking drugs for arterial hypertension. The pluri-metabolic syndrome was present in 41.6% of patients. RESULTS: Mean follow-up was 4 years. BMI reduction and weight loss were not large. 2 patients who had severe longstanding diabetes type 2 needed a second operation of the classical BPD because of failure in improving diabetes. Another 2 patients were changed to classical BPD because of a relapsing chronic duodeno-ileal ulcer. The incidence of ileal ulcer was 29.1%. Regarding hypercholesterolemia, hypertrigliceridemia, and type 2 diabetes when there is a good pancreatic "reservoir", the operation seems effective in the long-term. Protein absorption is better than that obtained with the classical BPD. CONCLUSIONS: Our long-term results suggest that in carefully selected patients suffering from serious hypercholesterolemia or type 2 diabetes with insulin reserves still at an acceptable level, and with BMI 30-40, DS without gastric resection can be proposed as a surgical treatment for metabolic diseases but not for obesity.

Impact of age on long-term complications after biliopancreatic diversion.

BACKGROUND: The aim of the study is to evaluate the importance of age on the mid- and long-term results and complications after biliopancreatic diversion (BPD). METHODS: Our study comprises 132 morbidly obese patients who underwent Scopinaro BPD from February 1995 to April 2001, with follow-up from 24 to 96 months. The patients, 53 males (40%) and 79 females (60%), with mean preoperative BMI 50.2 (35.4-81.5), and mean age 42 (20-65), were divided in 4 groups. Group A age 20-35, 43 patients; Group B age 36-45, 33 patients; Group C age 46-55, 31 patients and Group D age >55, 25 patients. Incidence of long-term specific complications after BPD were analyzed, including protein malnutrition, reversals, anastomotic ulcer, and incisional hernia. RESULTS: Mean postoperative BMI was similar in all Groups. After 60 months the following BMI values were observed. Group A 30.8, Group B 34.9, Group C 35.9, Group D 32. Incidence of long-term complications were not significantly different (chi(2)) in the 4 Groups, and were respectively: protein malnutrition 6.9%, 12.1%, 6.4%, 16.0%; anastomotic ulcer 11.6%, 9%, 6.4%, 16.0%; reversal 2.3%, 9.0%, 1.32%, 8.0%; ventral hernia 34.8%, 45.4%, 54.8%, 32.0%. CONCLUSIONS: From the preliminary results, it appeared that the incidence of the complications was higher in group D (>55 years old), whereas group C (46-55 years old) showed a lower complication rate. However, the prevalence of complications in all groups was not statistically different on chi(2) analysis. No age limit for bariatric surgery could be determined from the age ranges studied.