SAR user guide to the rectal MR synoptic report (primary staging).

Rectal MR is the key diagnostic exam at initial presentation for rectal cancer patients. It is the primary determinant in establishing clinical stage for the patient and greatly impacts the clinical decision-making process. Consequently, structured reporting for MR is critically important to ensure that all required information is provided to the clinical care team. The SAR initial staging reporting template has been constructed to address these important items, including locoregional extent and factors impacting the surgical approach and management of the patient. Potential outputs to each item are defined, requiring the radiologist to commit to a result. This provides essential information to the surgeon or oncologist to make specific treatment deisions for the patient. The SAR Initial Staging MR reporting template has now been officially adopted by the NAPRC (National Accreditation Program for Rectal Cancer) under the American College of Surgery. With the recent revisions to the reporting template, this user guide has been revamped to improve its practicality and support to the radiologist to complete the structured report. Each line item of the report is supplemented with clinical perspectives, images, and illustrations to help the radiologist understand the potential implications for a given finding. Common errors and pitfalls to avoid are highlighted. Ideally, rectal MR interpretation should not occur in a vacuum but in the context of a multi-disciplinary tumor board to ensure that healthcare providers use common terminology and share a solid understanding of the strengths and weaknesses of MR.

Guidelines for MR imaging in rectal cancer: Europe versus United States.

The aim of this study was to compare and contrast recently published guidelines for staging and reporting of MR imaging in rectal cancer from the European Society of Gastrointestinal and Abdominal Radiology and the North American Society of Abdominal Radiology. These guidelines were assessed on the presence of consensus and disagreement. Items were compared by two reviewers, and items with agreement and disagreement between the guidelines were identified and are presented in the current paper. Differences between guidelines are discussed to offer insights in practice variations between both continents and among expert centers, which to some extent may explain the differences between guidelines.

Changes in the multidisciplinary management of rectal cancer from 2009 to 2015 and associated improvements in short-term outcomes.

AIM: Significant recent changes in management of locally advanced rectal cancer (LARC) include preoperative staging, use of extended neoadjuvant therapies and minimally invasive surgery (MIS). This study was aimed at characterizing these changes and associated short-term outcomes. METHOD: We retrospectively analysed treatment and outcome data from patients with T3/4 or N+ LARC ≤ 15 cm from the anal verge who were evaluated at a comprehensive cancer centre in 2009-2015. RESULTS: In total, 798 patients were identified and grouped into five cohorts based on treatment year: 2009-2010, 2011, 2012, 2013 and 2014-2015. Temporal changes included increased reliance on MRI staging, from 57% in 2009-2010 to 98% in 2014-2015 (P < 0.001); increased use of total neoadjuvant therapy, from 17% to 76% (P < 0.001); and increased use of MIS, from 33% to 70% (P < 0.001). Concurrently, median hospital stay decreased (from 7 to 5 days; P < 0.001), as did the rates of Grade III-V complications (from 13% to 7%; P < 0.05), surgical site infections (from 24% to 8%; P < 0.001), anastomotic leak (from 11% to 3%; P < 0.05) and positive circumferential resection margin (from 9% to 4%; P < 0.05). TNM downstaging increased from 62% to 74% (P = 0.002). CONCLUSION: Shifts toward MRI-based staging, total neoadjuvant therapy and MIS occurred between 2009 and 2015. Over the same period, treatment responses improved, and lengths of stay and the incidence of complications decreased.

Diagnostic accuracy of ¹8F-FDG PET/CT for detection of advanced colorectal adenoma.

AIM: To determine the accuracy of 2-[(18)F]-fluoro-2-deoxy-d-glucose (FDG) positron-emission tomography (PET) in the detection of advanced colorectal adenomas. MATERIALS AND METHODS: In this retrospective study, patient consent was waived by the institutional review board. Combined FDG whole-body PET and computed tomography (CT) images (2000-2009) were re-read and compared with reports of complete colonoscopy performed up to 1 year after the PET examination. One or more areas of focal colonic uptake greater than the background indicated a positive PET result, irrespective of standardized uptake value (SUV). Lesion and patient-level measures of PET accuracy with their 95% confidence intervals (CI) were calculated. RESULTS: One hundred and eighty patients undergoing colonoscopy with or without biopsy underwent PET within 1 year prior to colonoscopy. There were 92 women and 88 men (mean age 63.3 years). Indications for PET were extent of disease and treatment response in all cases. Patients had non-colorectal cancer (n = 160) or colon cancer (n = 20). One hundred and fourteen FDG-avid lesions were present. In 33, there was no colonoscopic correlate. Two hundred and fifty-eight biopsies revealed tubular adenomas (n = 91, one with intra-mucosal cancer), tubulovillous adenomas (n = 28), adenocarcinoma (n = 37), inflammation (n = 22), hyperplastic polyps (n = 54), serrated adenoma (n = 5), metastatic disease (n = 5), normal/benign mucosa or submucosal benign tumors (n = 13) or miscellaneous (n = 3). Per-lesion performance of PET showed a sensitivity of 38% (95% CI: 31-46; 64/167) for all adenomas and carcinomas and 58% (95% CI: 49-67; 57/98) for lesions ≥ 10 mm. At the patient level, for all adenomas and carcinomas the sensitivity was 54% (95% CI: 44-63; 61/113), specificity 100% (pre-defined), positive predictive value (PPV) 100% (pre-defined), and negative predictive value (NPV) 56% (95% CI: 47-65; 67/119). For patients with advanced adenoma, PET sensitivity was 49% (95% CI: 35-63; 26/53) specificity, 100%, PPV 100% and NPV 82% (95% CI: 76-88; 127/154). Five of 37 adenocarcinomas were not detected, one of which was mucinous at histology. CONCLUSION: FDG PET detected most cancers, but only identified one-half of patients harbouring advanced adenomas. Based on the data, PET cannot be relied upon to accurately identify patients with advanced adenoma.

Prognostic aspects of DCE-MRI in recurrent rectal cancer.

OBJECTIVE: To explore whether pre-reoperative dynamic contrast-enhanced (DCE)-MRI findings correlate with clinical outcome in patients who undergo surgical treatment for recurrent rectal carcinoma. METHODS: A retrospective study of DCE-MRI in patients with recurrent rectal cancer was performed after obtaining an IRB waiver. We queried our PACS from 1998 to 2012 for examinations performed for recurrent disease. Two radiologists in consensus outlined tumour regions of interest on perfusion images. We explored the correlation between K(trans), Kep, Ve, AUC90 and AUC180 with time to re-recurrence of tumour, overall survival and resection margin status. Univariate Cox PH models were used for survival, while univariate logistic regression was used for margin status. RESULTS: Among 58 patients with pre-treatment DCE-MRI who underwent resection, 36 went directly to surgery and 18 had positive margins. K(trans) (0.55, P = 0.012) and Kep (0.93, P = 0.04) were inversely correlated with positive margins. No significant correlations were noted between K(trans), Kep, Ve, AUC90 and AUC180 and overall survival or time to re-recurrence of tumour. CONCLUSION: K(trans) and Kep were significantly associated with clear resection margins; however overall survival and time to re-recurrence were not predicted. Such information might be helpful for treatment individualisation and deserves further investigation.

Goblet cell carcinoid neoplasm of the appendix: clinical and CT features.

PURPOSE: To describe the clinical and CT imaging features of goblet cell carcinoid (GCC) neoplasm of the appendix. METHODS AND MATERIALS: A computer search of pathology and radiology records over a 19-year period at our two institutions was performed using the search string "goblet". In the patients with appendiceal GCC neoplasms who had abdominopelvic CT, imaging findings were categorized, blinded to gross and surgical description, as: "Appendicitis", "Prominent appendix without peri-appendiceal infiltration", "Mass" or "Normal appendix". The CT appearance was correlated with an accepted pathological classification of: low grade GCC, signet ring cell adenocarcinoma ex, and poorly differentiated adenocarcinoma ex GCC group. RESULTS: Twenty-seven patients (age range, 28-80 years; mean age, 52 years; 15 female, 12 male) with pathology-proven appendiceal GCC neoplasm had CT scans that were reviewed. Patients presented with acute appendicitis (n=12), abdominal pain not typical for appendicitis (n=14) and incidental finding (n=1). CT imaging showed 9 Appendicitis, 9 Prominent appendices without peri-appendiceal infiltration, 7 Masses and 2 Normal appendices. Appendicitis (8/9) usually correlated with typical low grade GCC on pathology. In contrast, the majority of Masses and Prominent Appendices without peri-appendiceal infiltration were pathologically confirmed to be signet ring cell adenocarcinoma ex GCC. Poorly differentiated adenocarcinoma ex GCC was seen in only a small minority of patients. Hyperattenuation of the appendiceal neoplasm was seen in a majority of cases. CONCLUSIONS: GCC neoplasm of the appendix should be considered in the differential diagnosis in patients with primary appendiceal malignancy. Our cases demonstrated close correlation between our predefined CT pattern and the pathological classification.

Dynamic contrast enhanced-MRI for the detection of pathological complete response to neoadjuvant chemotherapy for locally advanced rectal cancer.

OBJECTIVE: To determine the ability of dynamic contrast enhanced (DCE-MRI) to predict pathological complete response (pCR) after preoperative chemotherapy for rectal cancer. METHODS: In a prospective clinical trial, 23/34 enrolled patients underwent pre- and post-treatment DCE-MRI performed at 1.5T. Gadolinium 0.1 mmol/kg was injected at a rate of 2 mL/s. Using a two-compartmental model of vascular space and extravascular extracellular space, K(trans), k(ep), v(e), AUC90, and AUC180 were calculated. Surgical specimens were the gold standard. Baseline, post-treatment and changes in these quantities were compared with clinico-pathological outcomes. For quantitative variable comparison, Spearman's Rank correlation was used. For categorical variable comparison, the Kruskal-Wallis test was used. P ≤ 0.05 was considered significant. RESULTS: Percentage of histological tumour response ranged from 10 to 100%. Six patients showed pCR. Post chemotherapy K(trans) (mean 0.5 min(-1) vs. 0.2 min(-1), P = 0.04) differed significantly between non-pCR and pCR outcomes, respectively and also correlated with percent tumour response and pathological size. Post-treatment residual abnormal soft tissue noted in some cases of pCR prevented an MR impression of complete response based on morphology alone. CONCLUSION: After neoadjuvant chemotherapy in rectal cancer, MR perfusional characteristics have been identified that can aid in the distinction between incomplete response and pCR. KEY POINTS: Dynamic contrast enhanced (DCE) MRI provides perfusion characteristics of tumours. These objective quantitative measures may be more helpful than subjective imaging alone Some parameters differed markedly between completely responding and incompletely responding rectal cancers. Thus DCE-MRI can potentially offer treatment-altering imaging biomarkers.

Prospective assessment of primary rectal cancer response to preoperative radiation and chemotherapy using 18-fluorodeoxyglucose positron emission tomography.

PURPOSE: The purpose of this prospective study was to determine the ability of fluorine-18 fluorodeoxyglucose positron emission tomography to assess extent of pathologically confirmed rectal cancer response to preoperative radiation and 5-fluorouracil-based chemotherapy. METHODS: Patients with primary rectal cancer deemed eligible for preoperative radiation and 5-fluorouracil-based chemotherapy because of a clinically bulky or tethered tumor or endorectal ultrasound evidence of T3 and/or N1 were prospectively enrolled. Positron emission tomography and CT scans were obtained before preoperative radiation and 5-fluorouracil-based chemotherapy (5,040 cGy to the pelvis and 2 cycles of bolus 5-fluorouracil with leucovorin) and repeated four to five weeks after completion of radiation and 5-fluorouracil-based chemotherapy. In addition to routine pathologic staging, detailed assessment of rectal cancer response to preoperative radiation and 5-fluorouracil-based chemotherapy was performed independently by two pathologists. Positron emission tomography parameters studied included conventional measures such as standardized uptake value (average and maximum), positron emission tomography-derived tumor volume (size), and two novel parameters: visual response score and change in total lesion glycolysis. RESULTS: Of 21 patients enrolled, prospective data (pretreatment and posttreatment positron emission tomography, and complete pathologic assessment) were available on 15 patients. All 15 demonstrated pathologic response to preoperative radiation and 5-fluorouracil-based chemotherapy. This was confirmed in 100 percent of the cases by positron emission tomography compared with 78 percent (7/9) by CT. In addition, one positron emission tomography parameter (visual response score) accurately estimated the extent of pathologic response in 60 percent (9/15) of cases compared with 22 percent (2/9) of cases with CT. CONCLUSIONS: This pilot study demonstrates that fluorine-18 fluorodeoxyglucose positron emission tomography imaging adds incremental information to the preoperative assessment of patients with rectal cancer. However, further studies in a larger series of patients are needed to verify these findings and to determine the value of fluorine-18 fluorodeoxyglucose positron emission tomography in a preoperative strategy aimed at identifying patients suitable for sphincter-preserving rectal cancer surgery.

Primary melanoma of the esophagus: radiologic and clinical findings in six patients.

PURPOSE: To evaluate the clinical and radiologic findings of primary melanoma of the esophagus. MATERIALS AND METHODS: A computer search of pathology, radiology, and cancer registry records from 1973 to 1998 revealed six patients with primary malignant melanoma of the esophagus whose radiographs were available for review. Six esophagograms, three contrast material-enhanced chest computed tomographic (CT) scans, and four chest radiographs were reviewed. Medical records were reviewed for presenting symptoms and clinical course. RESULTS: Six patients (age range, 63-78 years; mean age, 70 years) had histopathologically proved primary malignant melanoma of the esophagus. All patients presented with dysphagia or odynophagia of 6 weeks duration or less. Esophagography and chest CT showed polypoid, nonobstructing esophageal masses, which were mucosal (n = 5) or submucosal (n = 1) and which were located in the middle (n = 3), distal (n = 2), or proximal (n = 1) third of the esophagus. Five patients underwent esophagogastrectomy: Three died a mean of 5 months afterward, two were lost to follow-up, and one was alive 7 months later. CONCLUSION: Primary melanoma of the esophagus is rare. It is usually polypoid, intraluminal, and nonobstructive. As with other esophageal malignancies, the prognosis is dismal despite resection.

Barium swallows after free jejunal transfer: should they be performed routinely?

Fistula formation after free jejunal transfer for pharyngoesophageal reconstruction is a serious complication with potentially critical consequences. Barium swallow is used postoperatively to check for anastomotic competence before feeding but has been unreliable as a predictor of leak at our institution. The objective of this study was to evaluate the role of routine postoperative barium swallow in 41 consecutive jejunal transfers. Thirty-nine patients who underwent 41 consecutive free jejunal transfers had a routine barium swallow performed between postoperative days 12 and 17. Radiologic findings and clinical outcome were evaluated and correlated. All barium swallows were reviewed by a single experienced radiologist in a blinded fashion. One total and one partial flap failure necessitated a second free jejunal transfer. Pharyngocutaneous fistulae developed after nine free jejunal transfers, of which the barium swallow was normal in four (44 percent) and showed a leak in five (56 percent). In the 32 free jejunal transfers with no clinical leaks, 6 (19 percent) had radiologic leakage of contrast. Thus, barium swallow was normal in 30 patients and showed leakage in 11 patients. Normal barium swallow correlated with uncomplicated clinical course in 26 of 30 cases. In the remaining four cases (13 percent), however, a delayed fistula developed, which was secondary to flap necrosis in one case (negative predictive value 87 percent). On the other hand, radiologic leaks corroborated clinical fistula in 5 of 11 cases (45 percent), whereas no fistula developed in 6 cases (positive predictive value 46 percent). Of the five patients with clinical fistulae, four had early leaks (within 1 week), and the barium swallow did not provide additional information. The fifth patient developed a delayed leak 2 weeks after the barium swallow. Review of these barium swallows at the time of this study reversed the initial report of leakage in three patients, improving the predictive value to 63 percent. These patients had an uncomplicated clinical course. The positive predictive value of clinical assessment alone was 63 percent. We conclude that barium studies following free jejunal transfers can be difficult to interpret, but an experienced radiologist can improve their accuracy. A normal barium swallow, however, does not ensure an uneventful clinical course. Similarly, radiologic leaks do not imply a clinical complication of fistula. Clinical judgment should therefore be exercised in initiating oral intake after free jejunal transfer. Barium swallow should be used only as an adjunct to aid in patient management.

Clinical importance of reinterpretation of body CT scans obtained elsewhere in patients referred for care at a tertiary cancer center.

PURPOSE: To determine the frequency and clinical importance of discordance between the initial interpretation of computed tomographic (CT) scans of the body and subsequent interpretations in patients with biopsy-proved cancer. MATERIALS AND METHODS: The initial and reinterpretation reports for 213 CT scans of the body submitted for official review were compared independently by two radiologists. Sixty-nine sets of reports were excluded because the reviewing radiologists and the outside radiologists had prior CT scans from differing dates to use for comparison. One set of reports was excluded because of lack of clinical follow-up. RESULTS: The interpretations were graded as "agree" in 90 patients (63%), "major disagreement" in 24 patients (17%), and "minor disagreement" in 29 patients (20%). A theoretic change in treatment could have occurred in nine of 53 cases of disagreement (17%). An actual change in treatment occurred in five of 53 cases of disagreement (9%). CONCLUSION: Discordant interpretations were frequent (53 of 143 cases [37%]), were often major (24 of 143 cases [17%]), and resulted in actual treatment changes in five of all 143 cases (3%). Reinterpretation of body CT scans can have a substantial effect on the clinical care of individual patients with proved malignancy.

Barium enema following incomplete colonoscopy.

The purpose of this article is to describe our findings on barium enema in patients who have had incomplete colonoscopy. For patients undergoing colonoscopy and barium enema within 6-months of each other between 1991 and 1997, barium enemas were reevaluated for redundant anatomy as well as lesions. Seventy-seven women and 30 men underwent 108 barium enemas. The most common finding was a redundant colon in 68% (55/81) of study patients, but only 33% (9/27) of control (complete colonoscopy) patients.

Patterns of neoplastic spread in colorectal cancer: implications for surveillance CT studies.

OBJECTIVE: This study was performed to assess patterns of metastatic disease shown on CT in colorectal cancer and to determine the diagnostic yield of routine pelvic CT in follow-up surveillance. MATERIALS AND METHODS: Pathology records and 3073 CT studies of 1119 patients with colorectal cancer were retrospectively reviewed. Primary tumor site, site of abdominal or pelvic metastases (liver, peritoneum, lymph nodes, local recurrence, or other), and incidental nonmetastatic pelvic disease were recorded. The superior iliac crests were considered the border between the abdomen (above) and the pelvis (below). RESULTS: Metastatic disease was present in 34% (1040/3073) of all CT studies: 33% (1007/3073) in the abdomen and 7% (227/3073) in the pelvis. Six percent (194/3073) of studies had metastases in both abdomen and pelvis. Forty-one percent (404/991) of studies showing abdominal primary colonic tumors showed metastatic disease: 40% (400/991) in the abdomen and 8% (78/991) in the pelvis. Four studies (0.4%; 4/991) in four different patients with abdominal primary colon tumors had isolated pelvic metastases; three of these were primary tumors of the cecum. Thirty-one percent (636/2082) of studies showing pelvic primary colonic tumors showed metastatic disease: 29% (607/2082) in the abdomen and 7% (149/2082) in the pelvis. Twenty-nine studies (1%; 29/2082) in 26 patients with pelvic primary colonic tumors revealed isolated pelvic metastases. CONCLUSION: In colorectal tumors arising within the abdomen, pelvic metastases are uncommon and isolated pelvic metastases are rare. Routine pelvic CT performed in the follow-up surveillance of patients with colorectal cancer with primary tumors arising in the abdominal portion of the colon has a low diagnostic yield.

Radiographic appearances of esophageal stents.

Among patients with esophageal carcinoma and associated dysphagia, more than 60% have unresectable disease at presentation. In such cases, the goal of treatment is primarily palliation of the dysphagia; treatment options include surgery, radiation therapy, laser ablation, and placement of stents. Beginning with the first stent-made of boxwood and silver in 1885-evolution in design led to the creation of large-diameter, rigid plastic stents placed at laparotomy and eventually placed by means of endoscopy. However, complications such as perforation, hemorrhage, dislodgment, pressure necrosis, and occlusion were frequently encountered with these stents. The development of small-diameter, expandable metal stents eliminated some of these complications. Metal stents have greatly reduced procedure-related morbidity and mortality, but complications such as perforation, malposition, migration, tumor ingrowth and overgrowth, food obstruction, and tracheoesophageal fistula persist. An efficacious and increasingly used method of treating malignant dysphagia, esophageal stent placement must undergo further improvements to reduce the frequency of complications, particularly migration and tumor ingrowth.

Herniation of the transverse colon after esophagectomy: is retrocardiac air a normal postoperative finding?

OBJECTIVE: This study describes the radiographic and CT imaging features of colonic herniation complicating esophagogastrectomy in three patients, all of whom required surgery. CONCLUSION: After routine esophagogastrectomy with gastric pull-through for esophageal carcinoma, the intrathoracic gastric pull-through most often lies in a right paraspinal location. Once a left-sided gastric pull-through has been excluded, radiologists must be suspicious for left retrocardiac air lucency that possibly represents herniation of the nearby colon. Early diagnosis is important for the prevention of bowel strangulation, especially of the ischemia-susceptible splenic flexure.

Barium sulfate: a new (old) contrast agent for diagnosis of postoperative esophageal leaks.

PURPOSE: To determine whether esophagography with use of barium alone is safe for detection of postoperative leaks of the esophagus. MATERIALS AND METHODS: A review was performed of 29 postoperative esophagograms that showed 29 leaks in 12 patients. All studies were performed with a 50% dilution of barium sulfate. Leak volumes were calculated as the product (in cubic centimeters) of the length, width, and height. The safety and efficacy of barium were determined on the basis of development of mediastinitis and retention of barium in the mediastinum that would interfere with subsequent patient care. RESULTS: In 11 of the 12 patients, follow-up studies were performed 4-48 days (mean, 10.2 days) after diagnosis. Leaks were 0.25-375 cm3 (mean, 31.4 cm3). In five of 17 (29%) follow-up procedures, small amounts of residual barium were detectable on the scout radiograph, none of which interfered with interpretation of the new images. During a follow-up period of 7-448 days (mean, 226 days), no cases of mediastinitis were found. CONCLUSION: Esophagography can be performed safely with barium to rule out an anastomotic esophageal leak.