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BACKGROUND: Multiple differentials exist for pediatric liver tumors under 2 years. Accurate imaging diagnosis may obviate the need for tissue sampling in most cases. OBJECTIVE: To evaluate the imaging features and diagnostic accuracy of computed tomography (CT) in liver tumors in children under 2 years. METHODS: Eighty-eight children under 2 years with treatment naive liver neoplasms and baseline contrast-enhanced CT were included in this institutional review board approved retrospective study. Two blinded onco-radiologists assessed these tumors in consensus. Findings assessed included enhancement pattern, lobulated appearance, cystic change, calcifications, central scar-like appearance, and metastases. The radiologists classified the lesion as hepatoblastoma, infantile hemangioma, mesenchymal hamartoma, rhabdoid tumor, or indeterminate, first based purely on imaging and then after alpha-fetoprotein (AFP) correlation. Multivariate analysis and methods of comparing means and frequencies were used for statistical analysis wherever applicable. Diagnostic accuracy, sensitivity, and positive predictive values were analyzed. RESULTS: The mean age of the sample was 11.4 months (95% CI, 10.9-11.8) with 50/88 (57%) boys. The study included 72 hepatoblastomas, 6 hemangiomas, 4 mesenchymal hamartomas, and 6 rhabdoid tumors. Presence of calcifications, multilobular pattern of arterial enhancement, lobulated morphology, and central scar-like appearance was significantly associated with hepatoblastomas (P-value < 0.05). Fourteen out of eighty-eight lesions were called indeterminate based on imaging alone; six lesions remained indeterminate after AFP correlation. Pure radiology-based diagnostic accuracy was 81.8% (95% CI, 72.2-89.2%), which increased to 92.1% (95% CI, 84.3-96.7%) (P-value > 0.05) after AFP correlation, with one hepatoblastoma misdiagnosed as a rhabdoid tumor. If indeterminate lesions were excluded for biopsy, the accuracy would be 98.8% (95% CI, 93.4-99.9%). CONCLUSION: CT had high accuracy for diagnosing liver neoplasms in the under 2-year age population after AFP correlation. Certain imaging features were significantly associated with the diagnosis of hepatoblastoma. A policy of biopsying only indeterminate lesions after CT and AFP correlation would avoid sampling in the majority of patients.
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Purpose: Magnetic resonance imaging (MRI) with the help of MRI-based tumor regression grade (mrTRG) score has been used as a tool to predict pathological tumor regression grade (pTRG) in patients of rectal cancer post-neoadjuvant chemoradiation. Our study aims to evaluate the ability of MRI in assessing treatment response comparing an objective mrTRG score and a subjective Likert score, with a focus on the ability to predict pathologic complete response (pCR). Methods: Post-treatment MRI studies were retrospectively reviewed for 170 consecutive cases of histopathologically proven rectal cancer after receiving neoadjuvant chemoradiation and prior to surgery by two oncoradiologists blinded to the eventual postoperative histopathology findings. An objective (mrTRG) and a subjective Likert score were assigned to all the cases. Receiver operating characteristic curves were constructed to determine the ability of Likert scale and mrTRG to predict pCR, with postoperative histopathology being the gold standard. The optimal cutoff points on the scale of 1 to 5 were obtained for mrTRG and Likert scale with the greatest sum of sensitivity and specificity using the Youden Index. Results: The most accurate cutoff point for the mrTRG to predict complete response was 2.5 (using Youden index), with a sensitivity of 69.2%, specificity of 69.6%, positive predictive value (PPV) of 85.6%, negative predictive value (NPV) of 46.4%, and accuracy of 69.3%. The most accurate cutoff for the Likert scale to predict complete response was 3.5, with a sensitivity of 47.5%, specificity of 89.1%, PPV of 91.9%, NPV of 39.4%, and accuracy of 59%. mrTRG had a lower cutoff and was more accurate in predicting pCR compared to Likert score. Conclusion: An objective mrTRG was more accurate than a subjective Likert scale to predict complete response in our study.
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PURPOSE: Evaluate MR patterns of response and their evolution in rectal cancer patients on watch and wait (WW). METHODS: We retrospectively reviewed 337 MRIs of 60 patients (median follow-up: 12 months; range: 6-49 months). Baseline MRIs (available in 34/60 patients) were evaluated for tumor morphology, location, thickness, circumferential involvement, nodal status and EMVI. First post-treatment MRIs (in all patients) were additionally evaluated for pattern of response on T2 and DWI. Change in post-treatment scar thickness and scar depth angle between the first and second post-treatment scans was also evaluated. Evolution of the response pattern/recurrence were evaluated till the last available scan. RESULTS: On the baseline scans, 20/34 (59%) patients had polypoidal tumor with 12/20 having ≤ 25% circumferential wall involvement. We saw five patterns of response-normalized rectal wall (2/60-3%), minimal fibrosis (23/60-38%), full thickness fibrosis (16/60-27%), irregular fibrosis (11/60-18%) and split scar (6/60-10%), with 2/60 (3%) showing possible residual disease. On the first post-treatment scans, 12/60 (20%) had restricted diffusion, with 3/12 having persistent restriction till last follow-up. Post-treatment fibrosis/split scar remained stable in 44/60 (73%) cases and improved further in the rest. 9/60 (15%) patients developed regrowth/recurrence. Patients with recurrence had < 10 mm scar thickness and < 21° change in scar angle between the first and second post-treatment MRIs. CONCLUSION: Most patients on WW protocol developed minimal or full thickness fibrosis, majority of which remained stable on follow-up.
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The Society of Abdominal Radiology's Colorectal and Anal Cancer Disease-Focused Panel (DFP) first published a rectal cancer lexicon paper in 2019. Since that time, the DFP has published revised initial staging and restaging reporting templates, and a new SAR user guide to accompany the rectal MRI synoptic report (primary staging). This lexicon update summarizes interval developments, while conforming to the original lexicon 2019 format. Emphasis is placed on primary staging, treatment response, anatomic terminology, nodal staging, and the utility of specific sequences in the MRI protocol. A discussion of primary tumor staging reviews updates on tumor morphology and its clinical significance, T1 and T3 subclassifications and their clinical implications, T4a and T4b imaging findings/definitions, terminology updates on the use of MRF over CRM, and the conundrum of the external sphincter. A parallel section on treatment response reviews the clinical significance of near-complete response and introduces the lexicon of "regrowth" versus "recurrence". A review of relevant anatomy incorporates updated definitions and expert consensus of anatomic landmarks, including the NCCN's new definition of rectal upper margin and sigmoid take-off. A detailed review of nodal staging is also included, with attention to tumor location relative to the dentate line and locoregional lymph node designation, a new suggested size threshold for lateral lymph nodes and their indications for use, and imaging criteria used to differentiate tumor deposits from lymph nodes. Finally, new treatment terminologies such as organ preservation, TNT, TAMIS and watch-and-wait management are introduced. This 2023 version aims to serve as a concise set of up-to-date recommendations for radiologists, and discusses terminology, classification systems, MRI and clinical staging, and the evolving concepts in diagnosis and treatment of rectal cancer.
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Neoplasias do Ânus , Radiologia , Neoplasias Retais , Humanos , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/terapia , Neoplasias do Ânus/diagnóstico por imagem , Neoplasias do Ânus/terapia , Neoplasias do Ânus/patologia , Reto/patologia , Estadiamento de Neoplasias , Imageamento por Ressonância Magnética/métodosRESUMO
BACKGROUND: Not all the significant progress made in the management of children with hepatoblastoma (HB) has translated into improved outcomes in limited-resource settings. There are limited data on outcomes in children with HB from India. METHODS: All patients diagnosed with HB between July 2013 and December 2020 were risk-stratified and treated as per International Liver Tumor Strategy Group (SIOPEL). Patients with standard-risk HB received cisplatin monotherapy and those with high-risk HB received alternating cycles of cisplatin and the combination of carboplatin plus doxorubicin. Data regarding demographic details, chemotherapy, surgery, liver transplantation, outcomes, prognostic factors, and toxicity were collected. RESULTS: Of 157 patients with HB, 117 (74%) were high risk, 31 (20%) were standard risk, and nine (6%) unknown. Patients with standard-risk disease had excellent outcomes, with 3-year event-free survival (EFS) and overall survival (OS) of 96% and 100%, respectively. Among high-risk HB, six underwent orthotopic liver transplantation of which four were alive at last follow-up. The 3-year EFS and OS of patients with high-risk disease was 56% and 66%, respectively. Outcomes of patients with PRETEXT IV (3-year EFS: 42%, 3-year OS: 50%) and metastatic disease (3-year EFS: 30%, 3-year OS: 50%) were dismal. Patients with serum alpha-fetoprotein (AFP) reduction greater than 90% following two courses of chemotherapy had favorable outcomes; 3-year EFS: 80% versus 58% (p = .013) and 3-year OS: 95% vs. 68% (p < .01). Only two (6%) of 31 patients with relapse/refractory HB were alive at a median follow-up of 36 months, and both had received salvage chemotherapy and surgery. CONCLUSIONS: While children with standard-risk HB had excellent outcomes, those with high-risk disease continue to do poorly. Serial monitoring of serum AFP values is a cost-effective and reliable predictor of outcomes. Orthotopic liver transplantation remains a viable option for inoperable disease in resource-limited settings as well.
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Hepatoblastoma , Neoplasias Hepáticas , Criança , Humanos , Lactente , Hepatoblastoma/patologia , Cisplatino , Prognóstico , alfa-Fetoproteínas , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Recidiva Local de Neoplasia/patologia , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Carboplatina , DoxorrubicinaAssuntos
COVID-19/terapia , Alocação de Recursos para a Atenção à Saúde/estatística & dados numéricos , Oxigênio/provisão & distribuição , COVID-19/epidemiologia , Alocação de Recursos para a Atenção à Saúde/organização & administração , Hospitais/provisão & distribuição , Humanos , Índia/epidemiologia , Unidades de Terapia Intensiva/organização & administração , Unidades de Terapia Intensiva/provisão & distribuição , Oxigênio/uso terapêuticoRESUMO
OBJECTIVE: The Liver Imaging Reporting and Data System (LI-RADS) has been widely applied to CT and MR liver observations in patients at high-risk for hepatocellular carcinoma (HCC). We investigated the impact of CT vs MR in upgrading LI-RADS 3 to LI-RADS 5 observations using a large cohort of high-risk patients. METHODS: We performed a retrospective, longitudinal study of CT and MR radiographic reports (June 2013 - February 2017) with an assigned LI-RADS category. A final population of 757 individual scans and 212 high-risk patients had at least one LI-RADS 3 observation. Differences in observation time to progression between modalities were determined using uni- and multivariable analysis. RESULTS: Of the 212 patients with a LI-RADS 3 observation, 52 (25%) had progression to LI-RADS 5. Tp ranged from 64 - 818 days (median: 196 days). One hundred and three patients (49%) had MR and 109 patients (51%) had CT as their index study. Twenty-four patients with an MR index exam progressed to LI-RADS 5 during the follow-up interval, with progression rates of 22% (CI:13%-30%) at 1 year and 29% (CI:17%-40%) at 2 years. Twenty-eight patients with a CT index exam progressed to LI-RADS 5 during follow-up, with progression rates of 26% (CI:16%-35%) at 1 year and 31% (CI:19%-41%) at 2 years. Progression rates were not significantly different between patients whose LI-RADS 3 observation was initially diagnosed on MR vs CT (HR: 0.81, Pâ¯=â¯0.44). DISCUSSION: MR and CT modalities are comparable for demonstrating progression from LI-RADS 3 to 5 for high risk patients.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Carcinoma Hepatocelular/diagnóstico por imagem , Meios de Contraste , Humanos , Neoplasias Hepáticas/diagnóstico por imagem , Estudos Longitudinais , Imageamento por Ressonância Magnética , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios XRESUMO
Background Presence of extramural venous invasion (EMVI) is a poor prognostic factor for rectal cancer as per literature. However, India-specific data are lacking. Aim The aim of the study is to determine the prognostic significance of EMVI in locally advanced rectal cancer on baseline MRI. Materials and Methods We retrospectively reviewed 117 MRIs of operable non-metastatic locally advanced rectal cancers in a tertiary cancer institute. Three dedicated oncoradiologists determined presence or absence of EMVI, and its length and thickness, in consensus. These patients were treated as per standard institutional protocols and followed up for a median period of 37 months (range: 2-71 months). Kaplan-Meier curves (95% CI) were used to determine disease-free survival (DFS), distant-metastases free survival (DMFS), and overall survival (OS). Univariate analysis was performed by comparing groups with log-rank test. Results EMVI positive cases were 34/114 (29%). More EMVI-positive cases developed distant metastasis compared with EMVI-negative cases (14/34-41% vs. 22/83-26%). The difference, however, was not statistically significant ( p = 0.146). After excluding signet-ring cell cancers ( n = 14), EMVI showed significant correlation with DMFS ( p = 0.046), but not with DFS or OS. The median thickness and length of EMVI was 6 and 14 mm, respectively in patients who developed distant metastasis, as compared with 5 and 11 mm in those who did not, although this difference was not statistically significant. Conclusion EMVI is a predictor of distant metastasis in locally advanced non-metastatic, non-signet ring cell rectal cancers. EMVI can be considered another high-risk feature to predict distant metastasis.
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PURPOSE: Signet Ring Rectal Cancer (SRRC) of rectum is rare high-grade subtype with poor prognosis and characteristic histopathology. We evaluated its imaging appearance and correlated its outcomes. MATERIALS AND METHODS: We conducted a retrospective review of the rectal MRIs of 97 patients with rectal SRRC, evaluating tumor morphology, T2 signal, length, location, pattern of tumor growth, nodal status and location, EMVI (extramural vascular invasion), site of metastases, and response to chemotherapy. The tumor signal on T2W images was categorized into intermediate, T2 hyperintense, and fluid/mucin bright. Imaging findings were correlated with risk of metastatic/ recurrent disease, disease-free survival, and overall survival. RESULTS: The median age of patients of SRRC in our study was 35 years and more frequently found in male patients. The common imaging features of SRRC were T2-hyperintense signal (63%), infiltrative growth pattern (76%), positive MR CRM (Circumferential Resection Margin on MRI) (84%), presence of EMVI (51%), and advanced T and N stage (97% and 84%, respectively). Peritoneum and nodes were the most common sites of metastases. Raised serum CEA (Carcino-embryonic Antigen) levels, positive MR CRM status, extramesorectal adenopathy, and advanced N stage had statistically significant predictive value for recurrence or metastases. Elevated serum CEA levels (p = 0.019) and intermediate T2 signal (p = 0.012) demonstrated significant independent association with poor overall survival, while advanced N stage (p = 0.033) demonstrated significant independent association with worse disease-free survival in multivariate analysis. CONCLUSION: SRRC affected young patients and demonstrated T2-hyperintense signal and subepithelial spread in an infiltrative pattern. Elevated CEA levels and T2-intermediate signal intensity are independent predictors for worse overall survival and advanced nodal stage is independent prognostic factor of poor disease-free survival. MRI rectum can pinpoint the pathology given the distinct MRI morphology and age of presentation.
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Neoplasias Retais , Reto , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Invasividade Neoplásica/patologia , Recidiva Local de Neoplasia/diagnóstico por imagem , Estadiamento de Neoplasias , Prognóstico , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Reto/patologia , Estudos RetrospectivosRESUMO
Findings with uncertain clinical significance are frequently encountered on radiographs. A structure or opacity visible on radiographs could be due to several causes ranging from artifact or external structure to malignancy or a life-threatening process. The approach that a radiologist chooses to address ambiguous findings can have a significant impact on a patient's health. In this article we discuss the causes and impact of ambiguous findings on radiographs. We also discuss the various strategies radiologists can adopt to maximize clinical value and, when needed, reach a definite diagnosis.
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Radiologistas , Humanos , RadiografiaRESUMO
AIM: Assessing metastatic mesorectal nodal involvement is a challenge in rectal cancer, especially in the post chemoradiation setting. We aim to assess the accuracy of MRI for nodal restaging and the validity of SAR criteria (≥ 5 mm size being metastatic). MATERIALS AND METHODS: This was an IRB-approved retrospective study of 166 patients with locally advanced rectal cancers, operated after neoadjuvant treatment. Two dedicated oncoradiologists reviewed the 166 post-chemoradiation presurgical MRIs in consensus. Nodal size and morphology (shape, margins, and signal intensity) were noted. The most accurate cut-off for size for predicting positive pN status was determined using the Youden index. RESULTS: MRI understaged 30/166 (18%) and overstaged 40/166 (24%) patients using the SAR criteria. The most accurate cut-off for node size was 5.5 mm, with a sensitivity of 75%, specificity of 60.2%, PPV of 40.7%, NPV of 86.9% (95% CI:78-92.5%), accuracy of 64.2%, and area under the curve (AUC) 0.657 (95% CI-0.524-0.79). Morphological characteristics were not significant to determine involvement, with positive nodes including 42% of round and 31% of oval nodes, 40% of heterogeneous and 45% of homogeneous nodes, and 31% irregularly marginated and 46% nodes with regular margins being positive on pathology. MRI was accurate in predicting pathology for mucinous nodes in 9/29 (31%) cases. Seven cases which were yN2 on MRI and yN0 on pathology demonstrated mucinous changes on MRI and had acellular mucin on histopathology. CONCLUSIONS: MRI has good negative predictive value, poor positive predictive value and moderate accuracy in nodal restaging. The cut-off of 5.5 mm demonstrated in our study is close to the SAR cut-off of 5 mm in the post-treatment setting. MRI accuracy is lower in patients with mucinous nodes.
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Neoplasias Retais , Quimiorradioterapia , Humanos , Imageamento por Ressonância Magnética , Estadiamento de Neoplasias , Neoplasias Retais/diagnóstico por imagem , Neoplasias Retais/patologia , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
Dedifferentiated liposarcoma (DDLS) is characterized by a wide histopathological spectrum. Spindle cell type of rhabdomyoblastic dedifferentiation has been rarely described in case of DDLS. A 39-year-old male presented with a recurrent retroperitoneal tumor mass, diagnosed as well-differentiated liposarcoma, for which he underwent surgical excisions on two occasions, followed by adjuvant radiation therapy previously. Computed tomogram scan his of abdomen revealed a large-sized, fat-containing recurrent, retroperitoneal mass, measuring 18.1 cm in the largest dimension. Histopathologic examination of the resected tumor revealed distinct areas of well- and dedifferentiated liposarcoma, including areas reminiscent of a myxofibrosarcoma, further progressing into a high-grade spindle cell sarcoma with fascicular and "Herringbone-like" growth patterns (fibrosarcoma-like). Immunohistochemically, high-grade spindle cell sarcomatous (dedifferentiated) component displayed distinct positivity for desmin and MyoD1, along with focal tumor nuclei, showing nuclear positivity for myogenin. Both well-differentiated liposarcomatous and dedifferentiated components displayed diffuse, intense nuclear positivity for MDM2 (overexpression) and p16INK4A. Furthermore, upon testing tumor sections displaying spindly sarcomatous areas for MDM2 amplification, by FISH technique, nearly all tumor cells displayed MDM2 gene amplification. This case constitutes one of the rare cases of DDLS displaying spindle cell rhabdomyoblastic dedifferentiation. Its diagnostic and treatment implications are discussed herewith.
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Diferenciação Celular , Lipossarcoma/diagnóstico , Recidiva Local de Neoplasia , Abdome/diagnóstico por imagem , Adulto , Biomarcadores Tumorais , Diagnóstico Diferencial , Humanos , Hibridização in Situ Fluorescente , Lipossarcoma/cirurgia , Masculino , Proteínas Proto-Oncogênicas c-mdm2/genética , Rabdomiossarcoma/diagnóstico , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND AND AIMS: Besides providing a surgical roadmap, rectal MRI plays a major role in treatment planning. We recently started using a structured template for reporting rectal cancer via MRI. We study the impact of using this template at our hospital in terms of number of essential imaging parameters described in the reports as compared to the pre-template free-text reports. METHODS: A structured rectal MRI reporting template was created in consensus with members of the colorectal tumour board and was introduced in the department, which included 14 essential parameters to be mentioned in the reports. We conducted a retrospective analysis of rectal MRI reports of 100 cases with histologically proven rectal cancer, comprising 50 consecutive free-text reports before the template was introduced and 50 consecutive structured reports after its introduction, checking for the presence or absence of inclusion of the 14 parameters. An anonymous online feedback survey was conducted as well after the introduction of the template for the members of the colorectal tumour board. RESULTS: Overall, the total number of parameters reported increased from a median value of 10 (range 6-13) to 14 (range 12-14). The common unreported parameters prior to template introduction included T staging, presence or absence of restricted diffusion, anterior peritoneal reflection (APR) involvement, and presence or absence of extramural vascular invasion; these were reported in 16%, 22%, 30% and 50% respectively. These improved to 98-100% reporting after template introduction. Maximum improvement was in T staging (16% to 98%) (P < 0.0001), restricted diffusion on DWI (from 22% to 100%) (P < 0.0001) and APR involvement (from 30% to 100%) (P < 0.0001). The most common unreported parameter after template introduction was the "tumoral T2 signal intensity" (unreported in 4% cases). The results of the survey were as follows: 100% felt a decreased need to talk to the radiologist to clarify the report, 81.8% felt an improvement in the quality of reporting as compared to free style reports, and 91% felt that the new template is easier to interpret. CONCLUSION: The introduction of a structured template for rectal cancer significantly improved the quality of rectal MRI reports, along with the satisfaction of referring providers.
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CONTEXT: Radiologists as a group face unique occupational health hazards among which musculoskeletal injuries, chronic eye strain, and others are yet to receive adequate attention. Constant mental strain due to demanding turnaround times and work pressures may lead to burnout and depression. These combine to decrease overall work satisfaction and productivity. AIMS: To study the prevalence of various health issues faced by radiologists in India and to assess whether specific demographic and occupational factors are associated with an increased risk. SETTINGS AND DESIGN: Cross-sectional observational study conducted as a voluntary anonymous electronic survey. METHODS AND MATERIALS: A 36-item survey was sent to radiologists through email and social media. All respondents who completed survey were included in the study. Questions regarding workload, repetitive stress injuries, eye strain, burnout, and so on were asked. STATISTICAL ANALYSIS USED: Chi-square test was used to test significance of correlation (P < 0.05). RESULTS: In all, 383 radiologists completed the survey. A high prevalence of repetitive stress injuries, chronic eye strain, depression, and burnout was found. Significant correlation was found between repetitive stress injuries and burnout. Pre-Conception and Pre-Natal Diagnostic Techniques Act (PCPNDT) related issues and work overload were the most common causes of high stress levels. Radiologists whose practices followed ergonomic design showed significantly less prevalence of neck pain. CONCLUSION: Radiologists in India have a high prevalence of repetitive stress injuries, chronic eye strain, and burnout, along with unique mental stressors such as PCPNDT-related issues.
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PURPOSE: To assess whether CT morphology of adnexal lesions in postmenopausal women with history of non-ovarian cancer could be used to discriminate benign and malignant lesions, particularly focusing on applicability of the ACR criteria. MATERIALS AND METHODS: This was an IRB-approved HIPAA-compliant retrospective review of contrast-enhanced CTs of 199 women, 55 years and older. Lesions were classified as simple cystic, complex cystic, solid-cystic, or solid based on CT morphology, and were diagnosed as benign, indeterminate, or malignant on follow-up imaging or pathology. Associated metastatic disease was noted, if present. Findings were analyzed to correlate CT morphology, primary tumor pathology, and metastatic disease pattern with eventual lesion diagnosis. RESULTS: There were 223 adnexal lesions, including 123 (55%) simple cystic, 48 (22%) complex cystic, 40 (18%) solid-cystic, and 12 (5%) solid lesions. 186/223 (83%) lesions were benign, and 37/223 (17%) were malignant. Primary colorectal cancer was significantly associated with an increased likelihood of malignant adnexal lesions (OR 10.2, p < 0.001) compared to patients with other cancers. Adnexal malignancy was significantly associated with the presence of non-ovarian peritoneal metastases (p < 0.001). None of the simple cysts (including 85 cysts between 1-3 cm and 38 cysts > 3 cm) were found to be malignant (malignancy rate: 0.0%, 95% CI 0.0-3.0%). Complex cysts were more likely to be malignant than simple cysts (p = 0.002) and solid-cystic lesions were more likely to be malignant than complex cysts (p < 0.001). CONCLUSION: Simple adnexal lesions on CT in this cohort were unlikely to be malignant, supporting the ACR guidelines. A higher size threshold of 3 cm (vs. 1 cm) may be preferred in all cases of simple cysts for recommending further follow-up. However, more complex-appearing cysts need further evaluation as the risk of malignancy is increased. Peritoneal metastases have a significant correlation with malignant adnexal involvement.