Imaging of Anal Squamous Cell Carcinoma: Survey Results and Expert Opinion from the Rectal and Anal Cancer Disease-Focused Panel of the Society of Abdominal Radiology.

The role and method of image-based staging of anal cancer has evolved with the rapid development of newer imaging modalities and the need to address the rising incidence of this rare cancer. In 2014, the European Society of Medical Oncology mandated pelvic magnetic resonance imaging (MRI) for anal cancer and subsequently other societies such as the National Comprehensive Cancer Network followed suit with similar recommendations. Nevertheless, great variability exists from center to center and even within individual centers. Notably, this is in stark contrast to the imaging of the anatomically nearby rectal cancer. As participating team members for this malignancy, we embarked on a comprehensive literature review of anal cancer imaging to understand the relative merits of these new technologies which developed after computed tomography (CT), e.g., MRI and positron emission tomography/computed tomography (PET/CT). The results of this literature review helped to inform our next stage: questionnaire development regarding the imaging of anal cancer. Next, we distributed the questionnaire to members of the Society of Abdominal Radiology (SAR) Rectal and Anal Disease-Focused Panel, a group of abdominal radiologists with special interest, experience, and expertise in rectal and anal cancer, to provide expert radiologist opinion on the appropriate anal cancer imaging strategy. In our expert opinion survey, experts advocated the use of MRI in general (65% overall and 91-100% for primary staging clinical scenarios) and acknowledged the superiority of PET/CT for nodal assessment (52-56% agreement for using PET/CT in primary staging clinical scenarios compared to 30% for using MRI). We therefore support the use of MRI and PET and suggest further exploration of PET/MRI as an optimal combined evaluation. Our questionnaire responses emphasized the heterogeneity in imaging practice as performed at numerous academic cancer centers across the United States and underscore the need for further reconciliation and establishment of best imaging practice guidelines for optimized patient care in anal cancer.

Mucinous appendiceal neoplasms: classification, imaging, and HIPEC.

Recent advances, specifically cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (CRS/HIPEC), offer advantages compared to the traditional therapeutic approach of systemic chemotherapy in the treatment of peritoneal carcinomatosis from mucinous appendiceal neoplasms (MAN). This review provides an up-to-date, comprehensive summary of the histologic classification of MAN, reviews common imaging findings of mucoceles and pseudomyxoma peritonei, and describes the radiologist's role in the multidisciplinary care team in quantifying disease and in helping select patients for definitive surgery.

Imaging and Surgical Management of Anorectal Vaginal Fistulas.

Anorectal vaginal fistulas (ARVFs) can result in substantial morbidity and potentially embarrassing symptoms in adult women of all ages. Despite having what may be obvious clinical manifestations, the fistulas themselves can be difficult to identify with imaging. MRI is the modality of choice for the diagnosis and characterization of ARVFs. A dedicated protocol involving the use of vaginal gel and optimized imaging planes with respect to the vagina, as well as an understanding of the MRI pelvic floor anatomy, is crucial for reporting surgically relevant details. Ancillary findings such as postsurgical changes, inflammation, abscess, sphincter destruction, and neoplasm are well evaluated. Vaginography, contrast enema, endoscopic US, and CT can be highly useful complementary diagnostic examinations. The entities that result in ARVFs may be obstetric, inflammatory (eg, Crohn disease and diverticulitis), neoplastic, iatrogenic, and/or radiation induced. Surgical management is heavily dependent on the cause and complexity of the fistulizing disease, which are related to the location of the fistula in the vagina, the type and extent of fistula branching, the number of fistulas, sphincter tears, inflammation, and abscess. ©RSNA, 2018.