Response Evaluation Criteria in Gastrointestinal and Abdominal Cancers: Which to Use and How to Measure.

As the management of gastrointestinal malignancy has evolved, tumor response assessment has expanded from size-based assessments to those that include tumor enhancement, in addition to functional data such as those derived from PET and diffusion-weighted imaging. Accurate interpretation of tumor response therefore requires knowledge of imaging modalities used in gastrointestinal malignancy, anticancer therapies, and tumor biology. Targeted therapies such as immunotherapy pose additional considerations due to unique imaging response patterns and drug toxicity; as a consequence, immunotherapy response criteria have been developed. Some gastrointestinal malignancies require assessment with tumor-specific criteria when assessing response, often to guide clinical management (such as watchful waiting in rectal cancer or suitability for surgery in pancreatic cancer). Moreover, anatomic measurements can underestimate therapeutic response when applied to molecular-targeted therapies or locoregional therapies in hypervascular malignancies such as hepatocellular carcinoma. In these cases, responding tumors may exhibit morphologic changes including cystic degeneration, necrosis, and hemorrhage, often without significant reduction in size. Awareness of pitfalls when interpreting gastrointestinal tumor response is required to correctly interpret response assessment imaging and guide appropriate oncologic management. Data-driven image analyses such as radiomics have been investigated in a variety of gastrointestinal tumors, such as identifying those more likely to respond to therapy or recur, with the aim of delivering precision medicine. Multimedia-enhanced radiology reports can facilitate communication of gastrointestinal tumor response by automatically embedding response categories, key data, and representative images. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Diagnosing venous thromboembolism in pregnancy.

OBJECTIVE: We report the imaging outcomes of all pregnant patients referred for suspected thromboembolism over a 43-month period. METHODS: We identified 168 patients who underwent ventilation/perfusion (VQ) single-photon emission CT (SPECT), CT pulmonary angiography (CTPA) or a Doppler ultrasound scan of the lower legs, as well as a control group of 89 non-pregnant age- and sex-matched patients who underwent VQ SPECT during the same period. Imaging outcomes were recorded, and radiation doses were calculated for individual patients. RESULTS: VQ SPECT and CTPA were equally likely to diagnose pulmonary embolism (PE) in about one patient out of every seven patients investigated. One in three CTPA scans was of suboptimal quality. A Doppler ultrasound examination of the legs will find deep venous thrombosis much less often, in about 1 patient out of every 15 patients investigated. The prevalence of PE in pregnant patients (as diagnosed by VQ SPECT) was similar to that in the non-pregnant, age- and sex-matched control group. The effective dose and the absorbed radiation dose to the maternal breast were lower with VQ SPECT. The foetal dose is comparable for both VQ SPECT and CTPA. CONCLUSION: VQ SPECT and CTPA provide a similar diagnostic yield for diagnosing PE during pregnancy, but VQ SPECT does so with a lower radiation dose to the mother (effective dose and breast dose). ADVANCES IN KNOWLEDGE: Ours is the first report of the diagnostic performance of VQ SPECT, rather than planar VQ scans, in pregnancy in a routine clinical setting.

The role of routine clinical pretreatment 18F-FDG PET/CT in predicting outcome of colorectal liver metastasis.

OBJECTIVE: The aim of this study was to determine the value of SUV-based metabolic parameters derived from pretreatment F-FDG PET/CT of colorectal liver metastases in predicting disease response, progression-free survival (PFS), and overall survival (OS). PATIENTS AND METHODS: We retrospectively reviewed 70 colorectal patients with liver metastases who underwent pretreatment F-FDG PET/CT. SUVmean, SUVmax, TLG (total lesion glycolysis), metabolic tumor volume, and metabolic tumor diameter were the metabolic parameters derived from volume of interest analysis of the most FDG-avid liver lesion in each subject. Clinical and laboratory parameters were recorded. Tumor response was assessed by response evaluation criteria in solid tumors 1.1 criteria at 12 weeks after treatment. Associations between tumor response, metabolic parameters, and clinical/laboratory parameters were examined by 1-way analysis of variance. The relationship of the metabolic parameters with PFS and OS was determined by Kaplan-Meier analyses and further confirmed with multivariate Cox regression analyses. RESULTS: SUVmean less than 4.48, SUVmax less than 6.59, TLG less than 75.2, metabolic tumor volume less than 4.49 cm, and hemoglobin level greater than or equal to 11 g/dL were associated with longer PFS (P < 0.05). Prior surgery or radiofrequency ablation to the liver metastases was the only additional factor shown to be associated with longer OS. CONCLUSIONS: SUV-based metabolic parameters derived from pretreatment F-FDG PET/CT can predict PFS in colorectal liver metastases.

Positron emission tomography-computed tomography in oesophageal cancer staging: a tailored approach.

BACKGROUND: Positron emission tomography-computed tomography (PET-CT) scanning is used routinely in the staging of oesophageal cancer to identify occult metastases not apparent on CT and changes the management in typically 3-18% patients. The authors aim to re-evaluate its role in the management of oesophageal cancer, investigating whether it is possible to identify a group of patients that will not benefit and can safely be spared from this investigation. METHODS: Consecutive patients with oesophageal cancer undergoing PET-CT staging between 2010 and 2013 were identified from a specialist modern multidisciplinary team database. Without knowledge of the PET-CT result, patients were stratified into low-risk or high-risk groups according to the likelihood of identifying metastatic disease on PET-CT based on specified criteria routinely available from endoscopy and CT reports. Clinical outcomes in the two groups were investigated. RESULTS: In 383 undergoing PET-CT, metastatic disease was identified in 52 (13.6%) patients. Eighty-three patients were stratified as low risk and 300 as high risk. None of the low-risk patients went on to have metastatic disease identified on PET-CT. Of the high-risk patients, 17% had metastatic disease identified on PET-CT. CONCLUSIONS: In one of the largest studies to date investigating the influence of staging PET-CT on management of patients with oesophageal cancer, the authors report a classification based on endoscopy/CT criteria is able to accurately stratify patients according to the risk of having metastatic disease. This could be used to avoid unnecessary PET-CT 22% of patients, saving cost, inconvenience and reducing potential delay to definitive treatment in this group.

Three-year clinical experience with VQ SPECT for diagnosing pulmonary embolism: diagnostic performance.

Ventilation-perfusion (VQ) single-photon emission computed tomography (SPECT) comprised the administration of SmartVent (n=386) or Technegas (n=1564) and 200 MBq (99m)Tc-MAA. 1406 scans were normal, 462 showed PE, 61 showed a singular subsegmental mismatched defect, 21 scans were non-diagnostic. 26% of scans performed with Technegas showed PE, compared to 15% with SmartVent. VQ SPECT had a sensitivity of 95.7%, specificity 98.6%, positive predictive value 95.7%, negative predictive value 98.6%. A normal VQ SPECT scan implied a more than ten-fold lower cause-specific mortality (1 in 1406) than a scan showing PE (1 in 116). NPV of a negative D-dimer was 94.3%.

Positron emission tomography computed tomography in oncology.

The role of positron emission tomography computed tomography in oncological imaging has rapidly evolved. It has proven itself to be cost effective and alters patient management in a significant proportion of cases. This article discusses its current and future applications.

The effect of the choice of irrigation fluid on cardiac stress during transurethral resection of the prostate: a comparison between 1.5% glycine and 5% glucose.

PURPOSE: Variable amounts of irrigation fluid are absorbed during transurethral prostate resection. Previous studies suggest that cardiac stress occurs as a result of transurethral prostate resection, possibly due to glycine absorption. We performed a prospective, blinded, randomized trial comparing 1.5% glycine with 5% glucose irrigating solution. We assessed whether glycine or glucose irrigation for transurethral prostate resection is associated with cardiotoxicity, as measured by troponin I and echocardiogram changes. MATERIALS AND METHODS: Between December 2001 and March 2003, 250 patients were recruited. Changes in immediate postoperative vs preoperative echocardiogram and serum cardiac troponin I indicated perioperative myocardial stress. Intraoperative irrigating fluid absorption was measured with 1% ethanol as a marker. Operative details recorded were anesthesia type, resection time, resected tissue weight and temperature change. Blood loss was measured with transfusions considered. Postoperatively blood assessments included serum glycine assay. RESULTS: Five patients (4%) in the glycine group and 3 (2%) in the glucose group had significantly increased troponin I after surgery. Of these men 1 per group had myocardial infarction and the remainder had transient ischemia. Logistic regression was used to identify factors associated with an unfavorable outcome, which was recorded as a significant increase in troponin I or ischemic changes on echocardiography. Increasing patient age and blood loss were associated with an unfavorable outcome (OR 1.84 and 1.24, respectively). We noted no significant differences in the 1.5% glycine and 5% glucose groups with regard to troponin I/echocardiogram. However, when the glycine assay was compared with adverse outcomes, an increased glycine assay was found to be associated with echocardiogram changes (p = 0.001) and with increased troponin I levels (relative risk 10.71). CONCLUSIONS: Transurethral prostate resection has an effect on the myocardium perioperatively. Glycine absorption causes echocardiogram changes and it is associated with increased troponin I. Increasing patient age and blood loss are associated with myocardial insult. The risk of increased blood loss was accumulative with each unit lost. Unrecognized blood loss or glycine absorption may explain the increase in morbidity and mortality previously reported in patients who undergo transurethral prostate resection.

Fear of injury in gymnastics: self-efficacy and psychological strategies to keep on tumbling.

The aim of this study was to examine female gymnasts' fear of injury, their sources of self-efficacy and the psychological strategies used to overcome their fears. The participants were 10 female gymnasts aged 12 - 17 years. They had all taken part in competitive gymnastics and had experienced some type of injury during their careers. Individual interviews were conducted using a structured interview guide. Data were analysed using an inductive content analysis. The results indicated that gymnasts were most fearful of injuries because of the difficulty in returning from an injury and being unable to participate in practices and competitions while injured. Gymnasts described aspects of their past performance experience, such as success, consistency and communication with significant others, as important sources of self-efficacy. Some examples of psychological strategies used to overcome their fear of injury were mental preparation (e.g. imagery, relaxation), just "going for a skill" and the coaches' influence.

A three-centre experience of orthotopic neobladder reconstruction after radical cystectomy: initial results.

OBJECTIVE: To assess, in a retrospective three-centre series, the initial experience and results of patients undergoing radical cystectomy and orthotopic neobladder reconstruction. PATIENTS AND METHODS: The medical records were retrospectively reviewed for 104 suitable consecutive patients undergoing radical cystectomy and orthotopic neobladder reconstruction between June 1994 and April 2003. The initial histology, operating times, transfusion rates, complications, mortality rates, continence rates, potency rates, and cancer control rates were recorded. RESULTS: The median (range) follow-up was 48 (6-113) months; 90 patients had a reconstruction with a 'Studer' neobladder, 12 with a 'Hautmann W pouch' and two with a 'T pouch' ileal neobladder. There were 24 early complications, and in eight patients re-operation was required; there was one death after surgery. There were 14 late complications and 10 patients required re-operation. The daytime continence rate was 99% and the nocturnal continence rate 78%. Five patients required intermittent self-catheterization. Twenty-two patients died from local and/or distant recurrences, and four from other causes. CONCLUSIONS: Orthotopic neobladder reconstruction provides excellent continence rates, and both acceptable complication and mortality rates. Suitable patients undergoing radical cystectomy should be offered orthotopic neobladder reconstruction.