What is the optimum post treatment surveillance imaging protocol for low-grade appendiceal mucinous neoplasms and pseudomyxoma peritoneii?

Appendiceal mucinous neoplasms are rare and can be associated with the development of disseminated peritoneal disease known as pseudomyxoma peritonei (PMP). Mucinous tumours identified on appendicectomy are therefore followed up to assess for recurrence and the development of PMP. In addition, individuals who initially present with PMP and are treated with cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC) are followed up to assess for recurrence. However, despite the concerted efforts of multiple expert groups, the optimal imaging follow-up protocol is yet to be established. The purpose of this article is to review the available evidence for imaging surveillance in these populations to identify the optimum post-resection imaging follow-up protocol.

Peritoneal malignancy: anatomy, pathophysiology and an update on modern day imaging.

With increasing subspecialised experience in radical cytoreductive surgery and intra-abdominal chemotherapy for peritoneal malignancy, outcomes have improved significantly in selected patients. The surgery and the treatment regimens are radical and therefore correct patient selection is critical. The radiologist plays a central role in this process by estimating, as precisely as possible, the pre-treatment disease burden. Because of the nature of the disease process, accurate staging is not an easy task. Tumour deposits may be very small and in locations where they are very difficult to detect. It must be acknowledged that no form of modern day imaging has the capability of detecting the smallest peritoneal nodules, which may only be visible to direct inspection or histopathological evaluation. Nonetheless, it behoves the radiologist to be as exact and precise as possible in the reporting of this disease process. This is both to select patients who are likely to benefit from radical treatment, and just as importantly, to identify patients who are unlikely to achieve adequate cytoreductive outcomes. In this review, we outline the patterns of spread of disease and the anatomic basis for this, as well as the essential aspects of reporting abdominal studies in this patient group. We provide an evidence-based update on the relative strengths and limitations of our available multimodality imaging techniques namely CT, MRI and positron emission tomography/CT.

An abbreviated MRI protocol for surveillance of cystic pancreatic lesions.

PURPOSE: Cystic pancreatic lesions (CPLs) are common and increasingly encountered in clinical radiology practice. The appropriate imaging surveillance strategy for lower-risk CPLs (branch duct-intraductal papillary mucinous neoplasms and indeterminant small cystic lesions) has been a topic of intense study and debate in recent years. MRI is considered the investigation of choice for initial characterisation and follow-up of CPLs. Follow-up intervals for CPLs vary from 6 months to 2 years and surveillance may be lifelong or until the patient is no longer considered fit for potential surgical intervention. This creates a significant burden on MRI resources as a standard protocol pancreatic MRI may have an acquisition time of up to 35-50 min. However, the necessity of contrast-enhanced sequences and diffusion weighted imaging (DWI) for routine follow-up of CPLs has been questioned in recent years. METHODS: We reviewed the available evidence to determine whether an abbreviated MRI (A-MRI) protocol may be safely adopted for surveillance of CPLs, as has been implemented in other clinical scenarios. RESULTS: A number of recent retrospective studies have indicated that an A-MRI, omitting contrast-enhanced and DWI, may be used for CPL surveillance without any suspicious features or cases of malignancy being missed. Although small number of cases may need to be recalled for additional MR sequences based on the A-MRI findings, there is still a significant overall timesaving. CONCLUSION: The best available evidence currently suggests that an A-MRI protocol should be considered for routine surveillance of CPLs. Prospective studies are required to ensure the findings reported in these retrospective case studies are backed up in ongoing clinical practice.

Integrated multimodality and multi-disciplinary team approach to pre-sacral lesions.

The purpose of this article is to describe the clinical and radiological features of presacral lesions. CT and MRI are the diagnostic modalities of choice and are complimentary in the assessment of presacral lesions. Imaging findings of presacral lesions on CT and MRI are described with the use of examples. Preoperative biopsy, surgical and non-surgical managements are outlined. While the general radiologist cannot be familiar with every rare presacral condition, characterisation of a presacral lesion based on anatomy, demographics and imaging features can guide us in making a sound differential.

Consensus Review of Discordant Imaging Findings after the Introduction of Digital Screening Mammography: Irish National Breast Cancer Screening Program Experience.

Background When there are discordant results between individual readers interpreting screening mammograms, consensus by independent readers may reduce unnecessary recalls for further work-up. Few studies have looked at consensus outcomes following the introduction of full-field digital mammography (FFDM). Purpose To determine outcomes of women discussed at consensus meetings during a 5-year period after introduction of FFDM, including recall rates, cancer detection, and interval cancers. Materials and Methods In this retrospective study from January 2010 to December 2014, the authors reviewed all screening mammograms from a single unit of a biennial Irish national breast screening program after the introduction of FFDM. Screening mammograms were double reported. Abnormalities detected at discordant screening mammography readings were discussed at biweekly consensus meetings. Outcomes of consensus meetings were reviewed in terms of referral for assessment, biopsy rates, cancer detection, and outcomes from later rounds of screening. Statistical analysis was performed by using a χ2 test to compare recall rate and cancer detection rates between FFDM and screen-film mammography based on a previously published study from the authors' institution. Results A total of 2565 women (age range, 50-64 years) with discordant mammographic findings were discussed at consensus meetings. Of these 2565 women, 1037 (40%) were referred for further assessment; 108 cancers were detected in these women. Of the 1285 women who returned to biennial screening, malignancy was detected at the site of original concern in 12 women at a further round of screening. Three true interval cancers were identified. Sensitivity (88.5% [108 of 122]; 95% confidence interval [CI]: 81.5%, 93.6%) and negative predictive value (99.1% [1528 of 1542]; 95% CI: 98.5%, 99.4%) of consensus review remained stable after the introduction of FFDM. Specificity of consensus review increased from 57.6% (729 of 1264; 95% CI: 54.9%, 60.4%) to 62.2% (1528 of 2457; 95% CI: 60.2%, 64.1%) (P = .008). Conclusion Consensus review of discordant mammographic screening-detected abnormalities remains a valuable tool after introduction of full-field digital mammography as it reduces recall for assessment and demonstrates persistently high sensitivity and negative predictive values. © RSNA, 2020 See also the editorial by Hofvind and Lee in this issue.

A National Bowel Cancer Screening Programme using FIT: Achievements and Challenges.

Colorectal cancer accounts for 11% of all cancer-related deaths in Ireland. With the aim of diagnosing these cancers at an earlier stage, and detecting premalignant lesions, the National Screening Service (NSS) offered a fecal immunochemical test (FIT) to all individuals aged 60 to 69. All individuals in the age range were contacted by post and invited to participate in the programme. Those with a positive FIT result were offered a colonoscopy in an internationally accredited unit. From an eligible population of 488,628, 196,238 individuals participated giving an uptake of 40.2%. Commencing at a FIT threshold of 20 µg Hg/g feces, the positivity rate was 8.6%, which overwhelmed colonoscopy capacity and, thus, the threshold was increased to 45 µg, resulting in an overall 5% positivity rate. A total of 520 individuals had cancer detected (68.3% stage I or II), of which 104 were removed endoscopically (pT1s). Adenomas were present in 54.2% of all colonoscopies, 17.4% deemed high risk. Despite a lower uptake, males were twice as likely to have colorectal cancers as females and had a 59% increased rate of high-risk adenomas diagnosed. Challenges facing the programme include increasing participation, especially among males, and increasing colonoscopy capacity. The ability to alter the sensitivity of FIT to match colonoscopy capacity is a valuable option for such a programme as it ensures that the maximum public health benefit can be achieved within available resources.

Correction to: Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting.

The article Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting, written by [§§§ AuthorNames §§§].

Magnetic resonance imaging for clinical management of rectal cancer: Updated recommendations from the 2016 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting.

OBJECTIVES: To update the 2012 ESGAR consensus guidelines on the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. METHODS: Fourteen abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) participated in a consensus meeting, organised according to an adaptation of the RAND-UCLA Appropriateness Method. Two independent (non-voting) Chairs facilitated the meeting. 246 items were scored (comprising 229 items from the previous 2012 consensus and 17 additional items) and classified as 'appropriate' or 'inappropriate' (defined by ≥ 80 % consensus) or uncertain (defined by < 80 % consensus). RESULTS: Consensus was reached for 226 (92 %) of items. From these recommendations regarding hardware, patient preparation, imaging sequences and acquisition, criteria for MR imaging evaluation and reporting structure were constructed. The main additions to the 2012 consensus include recommendations regarding use of diffusion-weighted imaging, criteria for nodal staging and a recommended structured report template. CONCLUSIONS: These updated expert consensus recommendations should be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI. KEY POINTS: • These guidelines present recommendations for staging and reporting of rectal cancer. • The guidelines were constructed through consensus amongst 14 pelvic imaging experts. • Consensus was reached by the experts for 92 % of the 246 items discussed. • Practical guidelines for nodal staging are proposed. • A structured reporting template is presented.

High-risk family colorectal cancer screening service in Ireland: Critical review of clinical outcomes.

BACKGROUND: We present the 15-year experience of a family colorectal cancer screening service in Ireland with emphasis on real life experience and outcomes. METHODS: Questionnaires were used to assess family cancer history and assign patients to risk categories; 'Moderate Risk', HNPCC, (suspected) genetic syndrome (non-HNPCC), 'Low Risk'. Screening was by full colonoscopy. We report neoplastic yield, examining effect of risk category, age, gender, and index colonoscopy findings. RESULTS: Between 1998 and 2013, 2242 individuals were referred; 57.3% female, 42.7% male, median age 46 years (range9-85yrs). Median follow up time was 7.9yrs (range 0.5-15.3yrs). Follow up data after exclusion (non-compliance, known CRC) was available in 1496 (66.7%): 'Moderate risk' 785 (52.5%), HNPCC 256 (17.1%), (suspected) genetic syndrome (non-HNPCC) 85 (5.7%), 'Low Risk' 370 (24.7%). Screening was performed in 1025(68.5%) patients; colonoscopy data available for 993 (96.9%); total 1914 colonoscopies. At index colonoscopy, 178 (18.0%) patients had adenomas; 56 (5.5%) advanced adenoma. During the entire study period, 240 (24.2%) had an adenoma; 69 (7.0%) advanced adenoma. Cancers were diagnosed on screening in 2 patients. Older age and male gender were associated with higher adenoma detection rate; p<0.001, p=0.01, respectively. Risk category did not affect adenoma yield. Adenoma and advanced adenoma detection at index colonoscopy were associated with detection of same at follow up screening; p<0.001. CONCLUSION: Male gender and age (>50) were the core identifiable risk factors for neoplasia at screening colonoscopy in this family screening setting. Our results would support less intensive surveillance in younger patients (<50), particularly where index colonoscopy is normal.

What the Radiologist Should Know About Treatment of Peritoneal Malignancy.

OBJECTIVE: The purpose of this article is to discuss the role of the radiologist in the treatment of peritoneal cancer, with focus placed on advanced treatment options and selection of patients with resectable disease for whom complete cytoreduction can be achieved. CONCLUSION: Peritoneal cancers traditionally have been associated with significant morbidity and universal mortality; however, the management of such cancers has evolved substantially. Advanced treatment options, including cytoreductive surgery and intraperitoneal chemotherapy, are associated with significantly improved long-term patient survival. To ensure that patients benefit from aggressive multimodality treatments, the radiologist plays a pivotal role in the multidisciplinary team to ensure careful patient selection, identifying individuals with resectable disease for whom complete cytoreduction can be achieved.

Impact of full field digital mammography on the classification and mammographic characteristics of interval breast cancers.

OBJECTIVE: Full field digital mammography (FFDM) is increasingly replacing screen film mammography (SFM) in breast screening programs. Interval breast cancers are an issue in all screening programs and the purpose of our study is to assess the impact of FFDM on the classification of interval breast cancers at independent blind review and to compare the mammographic features of interval cancers at FFDM and SFM. MATERIALS AND METHODS: This study included 138 cases of interval breast cancer, 76 following an FFDM screening examination and 62 following screening with SFM. The prior screening mammogram was assessed by each of five consultant breast radiologists who were blinded to the site of subsequent cancer. Subsequent review of the diagnostic mammogram was performed and cases were classified as missed, minimal signs, occult or true interval. Mammographic features of the interval cancer at diagnosis and any abnormality identified on the prior screening mammogram were recorded. RESULTS: The percentages of cancers classified as missed at FFDM and SFM did not differ significantly, 10.5% (8 of 76) at FFDM and 8.1% (5 of 62) at SFM (p=.77). There were significantly less interval cancers presenting as microcalcifications (alone or in association with another abnormality) following screening with FFDM, 16% (12 of 76) than following a SFM examination, 32% (20 of 62) (p=.02). CONCLUSION: Interval breast cancers continue to pose a problem at FFDM. The switch to FFDM has changed the mammographic presentation of interval breast cancer, with less interval cancers presenting in association with microcalcifications.

Magnetic resonance imaging for the clinical management of rectal cancer patients: recommendations from the 2012 European Society of Gastrointestinal and Abdominal Radiology (ESGAR) consensus meeting.

OBJECTIVES: To develop guidelines describing a standardised approach regarding the acquisition, interpretation and reporting of magnetic resonance imaging (MRI) for clinical staging and restaging of rectal cancer. METHODS: A consensus meeting of 14 abdominal imaging experts from the European Society of Gastrointestinal and Abdominal Radiology (ESGAR) was conducted following the RAND-UCLA Appropriateness Method. Two independent (non-voting) chairs facilitated the meeting. Two hundred and thirty-six items were scored by participants for appropriateness and classified subsequently as appropriate or inappropriate (defined by ≥ 80 % consensus) or uncertain (defined by < 80 % consensus). Items not reaching 80 % consensus were noted. RESULTS: Consensus was reached for 88 % of items: recommendations regarding hardware, patient preparation, imaging sequences, angulation, criteria for MRI assessment and MRI reporting were constructed from these. CONCLUSIONS: These expert consensus recommendations can be used as clinical guidelines for primary staging and restaging of rectal cancer using MRI. KEY POINTS: • These guidelines recommend standardised imaging for staging and restaging of rectal cancer. • The guidelines were constructed through consensus amongst 14 abdominal imaging experts. • Consensus was reached by in 88 % of 236 items discussed.

Cost-effectiveness of computed tomography colonography in colorectal cancer screening: a systematic review.

OBJECTIVES: The European Code Against Cancer recommends individuals aged ≥ 50 should participate in colorectal cancer screening. CT-colonography (CTC) is one of several screening tests available. We systematically reviewed evidence on, and identified key factors influencing, cost-effectiveness of CTC screening. METHODS: PubMed, Medline, and the Cochrane library were searched for cost-effectiveness or cost-utility analyses of CTC-based screening, published in English, January 1999 to July 2010. Data was abstracted on setting, model type and horizon, screening scenario(s), comparator(s), participants, uptake, CTC performance and cost, effectiveness, ICERs, and whether extra-colonic findings and medical complications were considered. RESULTS: Sixteen studies were identified from the United States (n = 11), Canada (n = 2), and France, Italy, and the United Kingdom (1 each). Markov state-transition (n = 14) or microsimulation (n = 2) models were used. Eleven considered direct medical costs only; five included indirect costs. Fourteen compared CTC with no screening; fourteen compared CTC with colonoscopy-based screening; fewer compared CTC with sigmoidoscopy (8) or fecal tests (4). Outcomes assessed were life-years gained/saved (13), QALYs (2), or both (1). Three considered extra-colonic findings; seven considered complications. CTC appeared cost-effective versus no screening and, in general, flexible sigmoidoscopy and fecal occult blood testing. Results were mixed comparing CTC to colonoscopy. Parameters most influencing cost-effectiveness included: CTC costs, screening uptake, threshold for polyp referral, and extra-colonic findings. CONCLUSION: Evidence on cost-effectiveness of CTC screening is heterogeneous, due largely to between-study differences in comparators and parameter values. Future studies should: compare CTC with currently favored tests, especially fecal immunochemical tests; consider extra-colonic findings; and conduct comprehensive sensitivity analyses.

Consensus review of discordant findings maximizes cancer detection rate in double-reader screening mammography: Irish National Breast Screening Program experience.

PURPOSE: To assesses consensus review of discordant screening mammography findings in terms of its sensitivity, safety, and effect on overall performance in the first 6 years of operation of the Irish National Breast Screening Program (NBSP). MATERIALS AND METHODS: Women who participated in the Irish NBSP gave written informed consent for use of their data for auditing purposes. Local ethics committee approval was obtained. The study population consisted of women who participated in the Irish NBSP and underwent initial screening mammography at one of the two screening centers serving the eastern part of Ireland between 2000 and 2005. Independent double reading of mammograms was performed. When the readers disagreed regarding referral, the case was reviewed by a consensus panel. Of the 128 569 screenings performed, 1335 (1%) were discussed by consensus. RESULTS: Of the 1335 cases discussed by consensus, 606 (45.39%) were recalled for further assessment. This resulted in an overall recall rate of 4.41%. In those recalled to assessment, 71 cases of malignant disease were diagnosed (ductal carcinoma in situ, n = 24; invasive cancer, n = 47). The remaining 729 patients were returned to biennial screening. Of these 729 patients, seven had false-negative findings that were identified in the subsequent screening round. Use of the highest reader recall method, in which a patient is recalled if her findings are deemed abnormal by either reader, could potentially increase the cancer detection rate by 0.6 per 1000 women screened but would increase the recall rate by 12.69% and the number of false-positive findings by 15.37%. CONCLUSION: The consensus panel identified 71 (7.33%) of 968 cancers diagnosed. Consensus review substantially reduced the number of cases recalled and was associated with a low false-negative rate.

Extension of hepatic necrosis secondary to current arcing to surgical clips: a potential complication of radiofrequency ablation.

The authors present a case report of a 67-year-old woman who underwent radiofrequency ablation of recurrent hepatic metastases. She was managed 2 years previously with a right hemi-hepatectomy. Subsequent to RF ablation she developed hepatic necrosis extending in a linear fashion to two of the metallic surgical clips at the free edge of the liver, consistent with current arcing.

CT colonography interpretation times: effect of reader experience, fatigue, and scan findings in a multi-centre setting.

Our purpose was to assess the effect of reader experience, fatigue, and scan findings on interpretation time for CT colonography. Nine radiologists (experienced in CT colonography); nine radiologists and ten technicians (both groups trained using 50 validated examinations) read 40 cases (50% abnormal) under controlled conditions. Individual interpretation times for each case were recorded, and differences between groups determined. Multi-level linear regression was used to investigate effect of scan category (normal or abnormal) and observer fatigue on interpretation times. Experienced radiologists (mean time 10.9 min, SD 5.2) reported significantly faster than less experienced radiologists and technicians; odds ratios of reporting times 1.4 (CI 1.1, 1.8) and 1.6 (1.3, 2.0), respectively (P

Polyp measurement and size categorisation by CT colonography: effect of observer experience in a multi-centre setting.

The extent measurement error on CT colonography influences polyp categorisation according to established management guidelines is studied using twenty-eight observers of varying experience to classify polyps seen at CT colonography as either 'medium' (maximal diameter 6-9 mm) or 'large' (maximal diameter 10 mm or larger). Comparison was then made with the reference diameter obtained in each patient via colonoscopy. The Bland-Altman method was used to assess agreement between observer measurements and colonoscopy, and differences in measurement and categorisation was assessed using Kruskal-Wallis and Chi-squared test statistics respectively. Observer measurements on average underestimated the diameter of polyps when compared to the reference value, by approximately 2-3 mm, irrespective of observer experience. Ninety-five percent limits of agreement were relatively wide for all observer groups, and had sufficient span to encompass different size categories for polyps. There were 167 polyp observations and 135 (81%) were correctly categorised. Of the 32 observations that were miscategorised, 5 (16%) were overestimations and 27 (84%) were underestimations (i.e. large polyps misclassified as medium). Caution should be exercised for polyps whose colonographic diameter is below but close to the 1-cm boundary threshold in order to avoid potential miscategorisation of advanced adenomas.

Virtual colonoscopy in the detection of colonic polyps and neoplasms.

First introduced in 1994, CT colonography (Virtual colonoscopy) has emerged as an accurate, non-invasive test that will likely play a future role in colorectal cancer screening. Over the past 3 years, there have been dramatic improvements in both hardware and software technology relating to CT colonography resulting in shorter scan times, enhanced user-friendliness and improved performance statistics. Published results show the accuracy of CT colonography to be comparable to conventional colonoscopy for detection of polyps >6mm in size with few false-positives. While many of the technical aspects of CT colonography have now been standardised current interest focuses on the development of faecal tagging agents to avoid full bowel catharsis and the use of low dose multislice CT acquisition to reduce patient radiation exposure. This chapter will summarise the development of CT colonography to date, document its published performance in detection of colorectal polyps and cancers, and review its current and potential future uses.