A radiologist's guide to novel anticancer therapies in the era of precision medicine.

Novel anticancer agents have replaced conventional chemotherapy as first line agents for many cancers, with continued new and expanding indications. Small molecule inhibitors act on cell surface or intracellular targets and prevent the downstream signaling that would otherwise permit tumor growth and spread. Anticancer antibodies can be directed against growth factors or may be immunotherapeutic agents. The latter act by inhibiting mechanisms that cancer cells use to evade the immune system. Hormonal agents act by decreasing levels of hormones that are necessary for the growth of certain cancer cells. Cancer therapy protocols often include novel anticancer agents and conventional chemotherapy used successively or in combination, in order to maximize survival and minimize morbidity. A working knowledge of anti-cancer drug classification will aid the radiologist in assessing response on imaging.

Step by Step: A Structured Approach for Proposing, Developing and Implementing a Radiology Peer Learning Program.

Similar to the experiences of other radiology practices, our radiology staff members felt that scored peer review identified few errors/learning opportunities while undermining team collegiality. They desired a more effective way to promote team collegiality and foster lifelong learning. We describe the steps our department took to transition from a peer review system to a peer learning program.

ACR Appropriateness Criteria® Dysphagia.

This review summarizes the relevant literature for the initial imaging of patients with symptoms of dysphagia. For patients with oropharyngeal dysphagia who have an underlying attributable cause, a modified barium swallow is usually appropriate for initial imaging but for those who have unexplained dysphagia a fluoroscopic biphasic esophagram is usually appropriate. Fluoroscopic biphasic esophagram is usually appropriate for initial imaging in both immunocompetent and immunocompromised patients who have retrosternal dysphagia. For postoperative patients with dysphagia, fluoroscopic single-contrast esophagram and CT neck and chest with intravenous (IV) contrast are usually appropriate for oropharyngeal or retrosternal dysphagia occurring in the early postoperative period where water-soluble contrast is usually preferred rather than barium sulfate. In the later postoperative period (greater than 1 month), CT neck and chest with IV contrast and fluoroscopic single-contrast esophagram are usually appropriate. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Acute Nonlocalized Abdominal Pain.

The range of pathology in adults that can produce abdominal pain is broad and necessitates an imaging approach to evaluate many different organ systems. Although localizing pain prompts directed imaging/management, clinical presentations may vary and result in nonlocalized symptoms. This review focuses on imaging the adult population with nonlocalized abdominal pain, including patients with fever, recent abdominal surgery, or neutropenia. Imaging of the entire abdomen and pelvis to evaluate for infectious or inflammatory processes of the abdominal viscera and solid organs, abdominal and pelvic neoplasms, and screen for ischemic or vascular etiologies is essential for prompt diagnosis and treatment. Often the first-line modality, CT quickly evaluates the abdomen/pelvis, providing for accurate diagnoses and management of patients with abdominal pain. Ultrasound and tailored MRI protocols may be useful as first-line imaging studies, especially in pregnant patients. In the postoperative abdomen, fluoroscopy may help detect anastomotic leaks/abscesses. While often performed, abdominal radiographs may not alter management. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Right Lower Quadrant Pain-Suspected Appendicitis.

Appendicitis remains the most common surgical pathology responsible for right lower quadrant (RLQ) abdominal pain presenting to emergency departments in the United States, where the incidence continues to increase. Appropriate imaging in the diagnosis of appendicitis has resulted in decreased negative appendectomy rate from as high as 25% to approximately 1% to 3%. Contrast-enhanced CT remains the primary and most appropriate imaging modality to evaluate this patient population. MRI is approaching CT in sensitivity and specificity as this technology becomes more widely available and utilization increases. Unenhanced MRI and ultrasound remain the diagnostic procedures of choice in the pregnant patient. MRI and ultrasound continue to perform best in the hands of experts. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Colorectal Cancer Screening.

This review summarizes the relevant literature regarding colorectal screening with imaging. For individuals at average or moderate risk for colorectal cancer, CT colonography is usually appropriate for colorectal cancer screening. After positive results on a fecal occult blood test or immunohistochemical test, CT colonography is usually appropriate for colorectal cancer detection. For individuals at high risk for colorectal cancer (eg, hereditary nonpolyposis colorectal cancer, ulcerative colitis, or Crohn colitis), optical colonoscopy is preferred because of its ability to obtain biopsies to detect dysplasia. After incomplete colonoscopy, CT colonography is usually appropriate for colorectal cancer screening for individuals at average, moderate, or high risk. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Porcelain Gallbladder: Is Observation a Safe Option in Select Populations?

BACKGROUND: Management of gallbladder wall calcifications has been controversial for many decades. Although the traditionally perceived strong association with gallbladder cancer mandated prophylactic cholecystectomy, newer evidence suggests a much lesser association and might indicate an observational approach. STUDY DESIGN: A retrospective cohort study of 113 patients with gallbladder wall calcifications diagnosed between 2004 and 2016 at a single institution was conducted. Radiographic re-review identified patients with definitive (n = 70) and highly probable (n = 43) gallbladder wall calcifications. Patients were categorized according to their designated treatment plan. RESULTS: In the observation group (n = 90), delayed cholecystectomy for gallbladder-related symptoms was necessary in 4 patients (4%). None of the patients in this group were diagnosed with a gallbladder malignancy during a mean of 3.2 ± 3.2 years follow-up. In the operative group (n = 23), peri-operative complications occurred in 13%, and gallbladder malignancy was found in 2 patients. In comparison, although patients in the observation group were older and had more comorbidities, the rate of adverse events was not significantly different (4% vs 13%; p = 0.15) with an overall low risk for potentially life-threatening complications to the patient when observed clinically. CONCLUSIONS: For management of gallbladder wall calcifications, observation appears to provide no significant difference in adverse events, including the risk of gallbladder malignancy developing, compared with an operative approach. Although there is a need for intervention in the presence of symptoms and findings suggestive of malignancy, prophylactic cholecystectomy should be avoided in patients with limited life expectancy and significant comorbidities.

ACR Appropriateness Criteria® Pretreatment Staging of Colorectal Cancer.

Colorectal cancers are common tumors in the United States and appropriate imaging is essential to direct appropriate care. Staging and treatment differs between tumors arising in the colon versus the rectum. Local staging for colon cancer is less integral to directing therapy given radical resection is often standard. Surgical options for rectal carcinoma are more varied and rely on accurate assessment of the sphincter, circumferential resection margins, and peritoneal reflection. These important anatomic landmarks are best appreciated on high-resolution imaging with transrectal ultrasound or MRI. When metastatic disease is suspected, imaging modalities that provide a global view of the body, such as CT with contrast or PET/CT may be indicated. Rectal cancer often metastasizes to the liver and so MRI of the liver with and without contrast provides accurate staging for liver metastases. This article focuses on local and distant staging and reviews the appropriateness of different imaging for both variants. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Computed tomography of miscellaneous regional and diffuse small bowel disorders.

This article reviews the computed tomography (CT) findings of miscellaneous regional and diffuse small bowel disorders. CT technique and potential pitfalls are discussed. Several categories of regional and diffuse small bowel conditions are reviewed, with representative CT images. These disorders often have relatively nonspecific CT appearances, and correlation with the history, clinical, and laboratory findings in each specific case is critical. In selected conditions, the CT findings are highly specific. The imaging literature of some of the common as well as some of the less common entities is reviewed, and clues to narrowing the differential diagnosis are provided.

Angiotensin-converting enzyme inhibitor-induced small-bowel angioedema: clinical and imaging findings in 20 patients.

OBJECTIVE: The purpose of this article is to retrospectively review the radiologic and clinical findings in patients with angiotensin-converting enzyme inhibitor (ACEI)-induced small-bowel angioedema, with an emphasis on CT findings. MATERIALS AND METHODS: Imaging findings, with an emphasis on CT, and clinical characteristics of 20 patients (23 presentations) presenting to two institutions' emergency departments from 1996 through 2010 with ACEI-induced small-bowel angioedema were retrospectively reviewed by two abdominal radiologists who were aware of the diagnosis. Examinations were reviewed in consensus to determine common radiographic findings. RESULTS: Patient age range was 23-83 years (mean, 56 years). Sixteen of the 20 patients were women, and 15 of 20 were obese. All had acute onset of severe abdominal pain. The date of the initial episode prompting CT evaluation ranged from 2 days to 10 years after the start of ACEI therapy (average, 3.3 years). All patients underwent abdominal CT examinations while symptomatic; five patients also underwent a small-bowel series. Three patients underwent urgent surgery for presumed small-bowel ischemia. All patients had resolution of symptoms within 4 days of hospitalization. CT findings included ascites in all patients, small-bowel wall thickening (mean, 1.3 cm), mild dilatation (mean, 2.9 cm), and straightening. There was no small-bowel obstruction. CONCLUSION: ACEI-induced small-bowel angioedema should be included in the differential diagnosis when patients receiving ACEI therapy present with abdominal complaints and the following combination of findings on CT examination: ascites, small-bowel wall thickening, dilatation without obstruction, and straightening.

Long-term follow-up after an initial episode of diverticulitis: what are the predictors of recurrence?

PURPOSE: The purpose of our study was to determine the clinical and CT predictors of recurrent disease after a first episode of diverticulitis that was successfully managed nonoperatively. METHODS: We retrospectively analyzed 954 consecutive patients who presented to our institution with diverticulitis from 2002 to 2008. Patients were identified with International Classification of Diseases, 9th Revision/Current Procedural Terminology codes. Patients were excluded if they had subsequent colectomy based on the first attack (n = 81), or if the attack they had between 2002 and 2008 was not their first attack (n = 201). We evaluated CT variables chosen by a panel of expert gastrointestinal radiologists. These radiologists reviewed the available published literature for CT imaging characteristics thought to predict diverticulitis severity. CT variables (n = 20) were determined by prospective reevaluation of scans by blinded study radiologists. Clinical variables (n = 43) were coded based on a retrospective chart review. Univariate analysis of variables in relation to recurrent disease was performed by a log-rank test of Kaplan-Meier estimates. Multivariate analysis was performed using Cox proportional hazards modeling. Variables with P < .2 on univariate analysis were included in a stepwise selection algorithm. RESULTS: The study population included 672 patients; mean age, 61 ± 15 years; mean follow-up, 42.8 ± 24 months. The index presentation of diverticulitis was most commonly located in the sigmoid colon (72%), followed by descending colon (33%), right colon (5%), and transverse colon (3%). Overall recurrence at 5 years was 36% by (95% CI 31.4%-40.6%) Kaplan-Meier estimate. Complicated recurrence (fistula, abscess, free perforation) occurred in 3.9% (95% CI 2.2%-5.6%) of patients at 5 years by Kaplan-Meier estimate. Family history of diverticulitis (HR 2.2, 95% CI 1.4-3.2), length of involved colon >5 cm (HR 1.7, 95% CI 1.3-2.3), and retroperitoneal abscess (HR 4.5, 95% CI 1.1-18.4) were associated with diverticulitis recurrence. Right colon disease (HR 0.27, 95% CI 0.09-0.86) was associated with freedom from recurrence. CONCLUSION: Although diverticulitis recurrence is common following an initial attack that has been managed medically, complicated recurrence is uncommon. Patients who present with a family history of diverticulitis, long segment of involved colon, and/or retroperitoneal abscess are at higher risk for recurrent disease. Patients who present with right-sided diverticulitis are at low risk for recurrent disease. These findings should be taken into consideration when counseling patients regarding the potential benefits of prophylactic colectomy.

Colonic diverticulitis: does age predict severity of disease on CT imaging?

PURPOSE: The aim of our study was to determine whether young patients with diverticulitis were more likely to present with abdominal CT evidence of severe disease. METHODS: We analyzed the abdominal CT scans of 932 patients who presented to our institution with CT scan findings consistent with diverticulitis from January 2002 through June 2007. Radiologists retrospectively reviewed all abdominal scans for the presence of imaging findings consistent with diverticulitis (bowel wall thickness, extraluminal air, free perforation, abscess, or fistula). The cohort was divided into 2 groups; patients 51 years of age. RESULTS: Two hundred forty-three patients were 51 years. Young patients were more likely to be male (63% vs 42%, P < .0001). Young patients had a higher proportion of scans with extraluminal air than older patients (19.7% vs 12.6%, P < .008). Young patients were more likely to present with severe disease found by CT than older patients (19.3% vs 11.5%). When we adjusted for gender, young males had a higher proportion of scans with extraluminal air than older males (22.4% vs 13.1%, P = .014). Young males were also more likely to present with severe disease (22% vs 12%). CONCLUSION: Young patients were more likely to have extraluminal air and severe disease found by CT. Young male patients presented more commonly with evidence of severe disease. They did not differ from older patients in rates of free perforation, abscess, or fistula formation.

Small bowel infarcts in Degos disease.

Degos disease is a rare idiopathic vasculopathy with multisystem involvement. We present a previously healthy 40-year-old woman who developed spontaneous small bowel infarctions and perforations 17 months after presentation with characteristic skin lesions. The abdominal CT findings of Degos disease, which have not been previously depicted in the radiology literature, are discussed.

Intramural fat in the duodenum and proximal small intestine in patients with celiac disease.

OBJECTIVE: The purpose of this article is to describe and illustrate intramural fat in the duodenum and jejunum, to our knowledge a previously undescribed finding in celiac disease. CONCLUSION: Celiac disease is known to produce inflammation of the duodenum and jejunum. We propose that postinflammatory intramural fat deposition occurs in a distribution likely unique for celiac disease. CT scans of the chest and abdomen obtained for many indications include these portions of the bowel. Celiac disease is now recognized as a common disease, and the recognition of intramural fat in the duodenum and jejunum on CT may allow earlier diagnosis.

Radiology of the laparoscopic Roux-en-Y gastric bypass procedure: conceptualization and precise interpretation of results.

Obesity is an epidemic in the United States. The laparoscopic Roux-en-Y gastric bypass procedure is an effective surgical intervention that can produce dramatic weight loss in morbidly obese patients. Despite the inherent risks, the surgery is increasing in popularity. Radiology plays a crucial role in postoperative evaluation. Upper gastrointestinal (UGI) series and abdominal computed tomography (CT) are the primary radiologic tools used in assessment of possible complications. With knowledge of the normal postoperative appearance, performance of UGI studies and interpretation of the results should be easy. The 24-hour postoperative examination allows reliable detection of anastomotic leaks. Although strictures of the gastrojejunal anastomosis are a common complication, they are often diagnosed and treated with endoscopy. In a thorough examination, one also evaluates for degraded pouch restriction, including a patulous gastrojejunal anastomosis or gastrogastric fistula, as a late cause of weight gain. Knowledge of the postoperative anatomy also assists in detection of internal hernias. CT is invaluable in detection and characterization of small bowel obstructions and internal hernias. CT may allow diagnosis of anastomotic leaks, abscesses, gastrogastric fistulas, and intra-abdominal hematomas. CT-guided percutaneous procedures, such as placement of gastrostomy tubes or drainage of fluid collections, can obviate emergency exploration and may be the only procedural intervention necessary for a cure.

An update on imaging of colorectal cancer.

Screening of asymptomatic average-risk patients for presence of colon cancer and early detection in precursor stages is of great interest to general population. Comprehensive evaluation of symptomatic or high-risk patients represents another important clinical focus. Available techniques for total colon imaging, rectal cancer staging and the role of positron emission tomography are discussed.