Myeloid Sarcoma: A Primer for Radiologists.

ABSTRACT: Myeloid sarcoma (MS) is a rare extramedullary neoplasm that can present in association with acute myeloid leukemia, most commonly in children younger than 15 years. This unique extramedullary malignancy may involve a variety of different organ systems and can present following, preceding, simultaneous with, or in insolation to acute myeloid leukemia. Common areas of extramedullary involvement include soft tissues, bones, lymph nodes, and the peritoneum. Imaging plays a critical role in the diagnosis and management of MS, with commonly used modalities including positron emission tomography-computed tomography, magnetic resonance imaging, computerized tomography, and ultrasound. The purpose of this review article is to provide radiologists with a comprehensive guide summarizing the relevant imaging and clinical features of MS, with emphasis on the role of imaging in the diagnosis, treatment, and follow-up of patients with MS. The relevant pathophysiology, epidemiology, clinical presentations, and differential diagnosis of MS will be reviewed. The relevance of different imaging modalities in diagnosis, monitoring of treatment response, and assessment of treatment-related complications will also be outlined. Through summarizing these topics, this review article aims to provide radiologists with a guide for understanding the existing knowledge of MS in the literature and the current role of imaging in the management of this unique malignancy.

Clinically Significant Prostate Cancer Detection After a Negative Prebiopsy MRI Examination: Comparison of Biparametric Versus Multiparametric MRI.

BACKGROUND. The frequency of clinically significant prostate cancer (csPCa) following negative biparametric MRI (bpMRI) and multiparametric MRI (mpMRI) has not been well investigated in direct comparative studies. OBJECTIVE. The purposes of this study were to compare the frequency of csPCa after negative prebiopsy bpMRI and mpMRI and to evaluate factors predictive of csPCa in the two cohorts. METHODS. This retrospective study included 232 men (mean age, 64.5 years) with negative bpMRI from August 2017 to March 2020 and 193 men (mean age, 69.0 years) with negative mpMRI from January 2018 to December 2018. PI-RADS category 1 or 2 was defined as negative. The study institution offered bpMRI as a low-cost self-pay option for patients without insurer coverage of prebiospy mpMRI. Patient characteristics and subsequent biopsy results were recorded. CsPCa was defined as Gleason score of 3 + 4 or greater. Multivariable regression analyses were performed to identify independent predictors of csPCa. The AUC of PSA density (PSAD) for csPCA was computed, and the diagnostic performance of PSAD was assessed at a clinically established threshold of 0.15 ng/mL2. RESULTS. Systematic biopsy was performed after negative bpMRI for 41.4% (96/232) of patients and after negative mpMRI for 30.5% (59/193) (p = .02). Among those undergoing biopsy, csPCa was present in 15.6% (15/96) in the bpMRI cohort versus 13.6% (8/59) in the mpMRI cohort (p = .69). The NPV for csPCa was 84% (81/96) for bpMRI and 86% (51/59) for mpMRI. In multivariable analyses, independent predictors of csPCa included smaller prostate volume (OR, 0.27; p < .001) and greater PSAD (OR, 3.09; p < .001). In multivariable models, bpMRI (compared with mpMRI) was not independently predictive of csPCa (p > .05). PSAD had an AUC for csPCa of 0.71 (95% CI, 0.56-0.87) in the bpMRI cohort versus 0.68 (95% CI, 0.42-0.93) in the mpMRI cohort. For detecting csPCa, a PSAD threshold of 0.15 ng/mL2 had NPV of 90% and PPV of 28%, in the bpMRI cohort versus NPV of 92% and PPV of 44% in the mpMRI cohort. CONCLUSION. The frequencies of csPCa were not significantly different at systematic biopsy performed after negative bpMRI and mpMRI examinations. PSAD had similar diagnostic utility for csPCa in the two cohorts. CLINICAL IMPACT. Either bpMRI or mpMRI, in combination with PSAD measurement, can help avoid negative prostate biopsies.

CAR T-Cell Therapy: An Update for Radiologists.

Chimeric antigen receptor-engineered (CAR) T-cell therapy is a promising novel immunotherapy that has the potential to revolutionize cancer treatment. Four CAR T-cell therapies have received FDA approval within the last 5 years, and the role of CAR T cells is anticipated to continue to evolve and expand. However, various aspects of CAR T-cell therapies remain poorly understood, and the therapies are associated with severe side effects, including cytokine release syndrome and immune effector cell-associated neurotoxicity, which require prompt diagnosis and intervention. The purposes of this review are to describe the role of imaging in diagnosing and monitoring toxicities from CAR T-cell therapies and explore the use of various imaging techniques, including PET/CT with novel radiotracers, to predict and assess treatment response and adverse effects. It is important for radiologists to recognize the imaging findings associated with each syndrome and to recognize the typical and atypical treatment response patterns associated with CAR T-cell therapy. Given the expected increase in use of CAR T cells in the near future, radiologists should familiarize themselves with the imaging findings encountered in these novel therapies so that they can provide comprehensive and up-to-date guidance for clinical management.

COVID-19 infection in the cancer population: a study of emergency department imaging utilization and findings.

PURPOSE: To analyze emergency department (ED) computerized tomography (CT) utilization in cancer patients with coronavirus disease 2019 (COVID-19). METHODS: A retrospective chart review was performed to identify cancer patients who received COVID-19 diagnosis within the single healthcare system and presented to the ED within 30 days of COVID-19 positive date between May 1 and December 31, 2020. RESULTS: In our 61 patients, the mean age was 72.5 years old, with 34% of patients (n = 21) on active cancer therapy and 66% (n = 40) on surveillance only. Most patients (n = 53) received their COVID-19 diagnosis within the ED, with 8 patients diagnosed prior to initial ED visit. The most common CT studies ordered within the ED were CT chest (n = 25), CT abdomen/pelvis (A/P) (n = 20), CT head (n = 8), and CT chest/abdomen/pelvis (C/A/P) (n = 7). COVID-19 findings were present on 33 scans, findings of worsening malignancy on 12 scans, and non-COVID non-cancer findings on 9 scans. Significant differences in CT severity score (p = 0.0001), indication for hospitalization (p = 0.026), length of hospitalization (p = 0.004), interventions (remdesivir, mechanical ventilation, and vasopressor support) while hospitalized (p < 0.05), and mortality (p = 0.042) were found between the prior diagnosis and ED diagnosis groups. No such differences were found between the active treatment and surveillance groups. CONCLUSION: ED CT imaging findings in patients with cancer and COVID-19 are predominantly related to COVID-19 infection, rather than cancer history or anti-cancer therapy status.

Decoding the Genomic Report for Radiologists.

OBJECTIVE. The purpose of this review is to provide a guide for radiologists that explains the language and format of modern genomic reports and summarizes the relevance of this information for modern oncologic imaging. CONCLUSION. Genomic testing plays a critical role in guiding oncologic therapies in the age of targeted treatments. Understanding and interpreting genomic reports is a valuable skill for radiologists involved with oncologic imaging interpretation.

A New Look at Toxicity in the Era of Precision Oncology: Imaging Findings, Their Relationship With Tumor Response, and Effect on Metastasectomy.

OBJECTIVE: As cancer care becomes increasingly personalized and patients with metastatic disease live longer, oncologists' approach to drug toxicity is also evolving. CONCLUSION: This article aims to broaden the radiologist's understanding of imaging-evident toxicity by describing how oncologists grade toxicity, exploring toxicity as a biomarker of treatment response, discussing the effect of toxicity in patients who are candidates for metastasectomy, and illustrating how combining drugs of varying classes amplifies toxicity.

Advanced High-Grade Serous Ovarian Cancer: Frequency and Timing of Thoracic Metastases and the Implications for Chest Imaging Follow-up.

PURPOSE: To study the frequency, timing, and associations of thoracic metastases in advanced (stage III and IV) high-grade serous ovarian cancer (HGSC) to help optimize the use of cross-sectional chest imaging. MATERIALS AND METHODS: This institutional review board-approved retrospective study with waived informed consent included 186 consecutive patients with pathologically proven advanced HGSC after primary cytoreduction (mean age ± standard deviation, 60 years ± 9.7) who underwent imaging at our tertiary cancer institution from January 2012 to December 2012 with at least 1 year of follow-up, unless there was thoracic metastasis or death. Electronic medical records and all available imaging studies were reviewed to record patient and tumor characteristics, frequency and timing of abdominal and thoracic metastases, and visibility of the first thoracoabdominal metastasis on abdominal images. Patient and tumor characteristics associated with thoracic metastases were studied by using univariate and multivariate Cox proportional analysis. RESULTS: After median follow-up of 57 months (interquartile range [IQR], 38-93), 175 patients (94%) developed metastatic disease; each had abdominal disease, and 76 (41%) had thoracic metastases. The first thoracoabdominal metastasis was visible on abdominal images in all 175 patients. The thoracic metastasis-free interval was longer than the abdominal disease-free interval (median, 85 months [IQR, 28-131] vs 14 months [IQR, 7-27], respectively; P < .0001). Presence of disease on abdominal images (hazard ratio, 2.56; 95% confidence interval: 1.35, 4.76) was the only factor independently associated with thoracic metastases. CONCLUSION: Thoracic metastases in advanced HGSC rarely occur before abdominal disease, and first thoracoabdominal metastases are invariably visible on abdominal images. Therefore, cross-sectional chest imaging may be deferred until development of abdominal disease, with minimal risk of missing thoracic metastases.

Role of Radiologists in Contract Research Organizations (CROs).

Clinical trials play a vital role in advancing technology and novel therapies in the healthcare world. However, the increasing scale of trials and the complexity of the regulatory approval process is often a barrier for those interested in conducting research. Contract research organizations (CROs) aim to address this problem by offering their infrastructure and expertise to bring a therapy from conception to approval without the need for in-house staff. Clinical trial imaging often plays an essential role in this process, creating a need for radiologists and a unique opportunity to provide irreplaceable value in their ability to interpret and analyze the imaging outcomes of therapies in question. This paper explores the concept of CROs, the crucial role played by radiologists in their operation, and the nature of the CRO - radiologist relationship.

Abdominopelvic CT Imaging Findings in the Emergency Department in Patients With HIV Positive Status: Single Institute Experience.

OBJECTIVE: To assess emergency department (ED) abdominopelvic computed tomography (CT) imaging utilization and findings in patients with known human immunodeficiency virus (HIV) positive status. MATERIALS AND METHODS: A retrospective chart review of imaging, clinical, and laboratory data was performed for HIV positive patients who demonstrated HIV-related findings on abdominopelvic CT imaging performed within the ED. RESULTS: One hundred and eighty-eight patients with 522 CT scans of the abdomen and/or pelvis were reviewed. 47 patients with HIV presenting to the ED on 82 separate occasions were included in this study (mean age 43.3 years). Patients presented to the ED with infectious/inflammatory disease (n = 54) or history of HIV-related malignancy or new/worsening HIV-related malignancy (n = 28). The most common findings on abdominopelvic CT were anorectal pathology including anorectal abscess or proctitis (n = 22), followed by colitis (n = 19). Findings of HIV-associated malignancy were less common, including anal/rectal cancer (n = 7), Kaposi's sarcoma (n = 4), and lymphoma (n = 2). At the time of ED visit, 25.6% (n = 21) of patients had acquired immunodeficiency syndrome (AIDS). Higher WBC counts were found in the infectious/inflammatory group (P = 0.021) and patients without AIDS (P = 0.0159), while lower WBC counts were associated with new or worsening malignancy (P = 0.007) and AIDS (P = 0.0000). Patients with AIDS were more likely to be deceased at the time of our study. CONCLUSIONS: The majority of ED visits within our population were attributed to infectious/inflammatory etiologies. CT findings demonstrated predominantly infectious/inflammatory processes, with anorectal pathology being the most common. Findings of malignancy on CT were less common, while opportunistic infections and AIDS-defining malignancies were uncommon.

Chest CT Findings in Patients with HIV Presenting to the Emergency Department: A Single Institute Experience.

PURPOSE: The aim of this study was to analyze chest CT imaging findings and relevant clinical factors in patients with HIV presenting to the emergency department (ED). MATERIALS AND METHODS: A retrospective review was performed to identify patients with HIV who received chest CT imaging evaluation in the acute ED setting. Analyzed patients included adults with a known diagnosis of HIV who presented to the ED at a single tertiary care center between 2004 and 2020 and received chest CT imaging. Chest CT findings were assessed by 2 radiologist readers, and relevant clinical data were gathered. Statistical analysis was performed to determine if imaging and clinical factors demonstrate significant associations with CD4 count, viral load, and antiretroviral therapy status. RESULTS: A total of 113 patients with HIV were identified who presented to the ED and underwent chest CT imaging evaluation (mean age 47 ± 11 years). Frequently detected chest CT findings included infectious pneumonia (24%), malignancy (11%), pleural effusion (17%), pericardial effusion (13%), and pulmonary embolism (4%). CD4 count, viral load, and active retroviral therapy demonstrated statistically significant associations with a number of key imaging and clinical factors, including presence of pneumonia, malignancy, average length of hospital admission, and survival. CONCLUSION: Patients with HIV present with a wide range of imaging findings when presenting in the acute ED setting. CD4 count, viral load, and active retroviral therapy status demonstrate statistically significant associations with multiple key imaging findings and clinical factors. Chest CT plays an integral role in the clinical management of this unique patient population.

The predictive impact of dual somatostatin receptor/fluorodeoxyglucose (FDG) positron emission tomography (PET) in metastatic gastroenteropancreatic neuroendocrine tumors (GEP-NETs): review of literature and a single institution experience.

Treatment with radiolabelled somatostatin analogs, a form of peptide receptor radionuclide therapy (PRRT), has changed the management of patients with advanced gastroenteropancreatic neuroendocrine tumors (GEP-NETs). There is a subgroup of patients who have suboptimal benefit and rapidly progress on PRRT, indicating that accurate prognostic and predictive markers are urgently needed. Currently, most of the literature concentrate on the prognostic impact of the dual positron emission tomography (PET) scan with very few information regarding the predictive value. We report a case series and review the literature to summarizes the predictive value of combined somatostatin receptor (SSTR) and fluorodeoxyglucose (FDG) PET in metastatic GEP-NETs. We conducted a review of the literature for data published from 2010 to 2021 in MEDLINE, Embase, the National Institutes of Health trial registry, Cochrane CENTRAL, and published proceedings from major gastrointestinal and neuroendocrine cancer meetings. Our main criteria included all published prospective and retrospective data in which the predictive value of dual PET scans using SSTR and FDG was correlated with PRRT response in patients with metastatic GEP-NETs. We summarized clinical outcomes including progression-free survival (PFS), overall survival (OS), and post-therapy complications associated with PRRT according to FDG avidity. We excluded studies that did not include FDG PET scan, GEP patients, studies with no clear predictive value of the FDG PET scan, and studies that did not report a direct correlation between FDG avidity and primary outcome. Additionally, we summarized our institutional experience in eight patients who progressed during or within the first year of PRRT treatment. Our search identified 1306 articles; most of them showed only the prognostic value of Integrated SSTR/FDG PET imaging biomarker in GEP-NETs. Only three studies (n=75 patients) met our inclusion criteria and retrospectively investigated the predictive value of dual SSTR and FDG imaging in subjects being considered for PRRT. The results confirmed that FDG avidity correlates with advanced NET grades. Lesions that are both SSTR and FDG avid had early disease progression. In one study, at multivariate analysis, FDG PET results were independently predictive of lower PFS for PRRT. In our case series, there were eight patients with metastatic well-differentiated GEP-NETs (grades 2 and 3) who progressed within one year of PRRT. Seven of them had positive FDG PET scan at the time of progression. In conclusion, Dual SSTR/FDG PET imaging has a potential predictive impact for PRRT in GEP-NETs. It permits the capturing of the disease complexity and aggressiveness, which correlates with PRRT response. Therefore, prospective future trials should validate the predictive value of dual SSTRs/FDG PET for better PRRT stratification.

Anorectal pathology in the HIV population: a guide for radiologists.

Patients with human immunodeficiency virus (HIV) can present with a wide range of different acute and chronic pathologies. Anorectal conditions are particularly common in this unique patient population, including pathologies, such as proctitis, anorectal abscess, anorectal fistula, and anal squamous cell carcinoma. The radiologist plays a critical role in the assessment of these common forms of anorectal disease, as these conditions can present with various findings on imaging assessment. Pelvic CT, MRI, and FDG-PET/CT are among the most common modalities used for assessment of anorectal disease in the HIV patient population. Knowledge of the fundamental clinical and imaging findings associated with these pathologies in HIV patients is critical for radiologists.

Primary peritoneal serous carcinoma: a primer for radiologists.

Primary peritoneal serous carcinoma (PPSC) is a rare primary peritoneal tumor characterized by a unique range of clinical features and imaging findings. Though it shares many clinical, histologic, and imaging features with serous ovarian carcinoma, it remains a distinct clinical entity. Although less common than its primary ovarian counterpart, PPSC is characterized by a prognosis that is often equally poor with presentations common in late stages of disease. Key imaging modalities used in the evaluation of PPSC include ultrasound, CT, MRI, and PET/CT. For radiologists, an understanding of the pertinent imaging findings, pathologic correlations, and clinical features of PPSC is essential for arriving at the correct diagnosis and guiding the subsequent appropriate management of this complex malignancy.

The modern therapeutic & imaging landscape of metastatic prostate cancer: a primer for radiologists.

Prostate cancer represents one of the leading causes of cancer-related mortality in the United States and the most common cancer among men. Treatment paradigms for the management of advanced stages of prostate cancer have continued to evolve in recent years. These advancements in the therapeutic landscape of metastatic prostate cancer and diagnostic imaging modalities have fundamentally changed the treatment of patients with prostate cancer. In this review article we provide a primer for radiologists highlighting the most recent developments in treatment options and imaging techniques utilized in the modern oncologic management of metastatic prostate cancer. We will examine current therapy options and associated toxicities with an emphasis on relevant imaging findings commonly encountered by radiologists. We also summarize the role of modalities including CT, MRI, PET, bone scintigraphy, and PET in the diagnosis and follow-up of patients with metastatic prostate cancer.

Overview of serum and tissue markers in colorectal cancer: a primer for radiologists.

Serum and tissue tumor markers provide crucial information in the diagnosis, treatment, and follow-up of colorectal cancers. Tissue tumor markers are increasingly used for determination of targeted chemotherapy planning based on genotyping of tumor cells. Recently, plasma-based technique of liquid biopsy is being evaluated for providing tumor biomarkers in the management of colorectal cancer. Tumor markers are commonly used in conjunction with imaging during initial staging, treatment determination, response assessment, and determination of recurrence or metastatic disease. Knowledge of tumor markers and their association with radiological findings is thus crucial for radiologists. Additionally, various novel imaging techniques are being evaluated as potential noninvasive imaging biomarkers to predict tumor genotypes, features, and tumor response. We review and discuss the potential role of these newer imaging techniques.

Stratification of cystic renal masses into benign and potentially malignant: applying machine learning to the bosniak classification.

PURPOSE: To create a CT texture-based machine learning algorithm that distinguishes benign from potentially malignant cystic renal masses as defined by the Bosniak Classification version 2019. METHODS: In this IRB-approved, HIPAA-compliant study, 4,454 adult patients underwent renal mass protocol CT or CT urography from January 2011 to June 2018. Of these, 257 cystic renal masses were included in the final study cohort. Each mass was independently classified using Bosniak version 2019 by three radiologists, resulting in 185 benign (Bosniak I or II) and 72 potentially malignant (Bosniak IIF, III or IV) masses. Six texture features: mean, standard deviation, mean of positive pixels, entropy, skewness, kurtosis were extracted using commercial software TexRAD (Feedback PLC, Cambridge, UK). Random forest (RF), logistic regression (LR), and support vector machine (SVM) machine learning algorithms were implemented to classify cystic renal masses into the two groups and tested with tenfold cross validations. RESULTS: Higher mean, standard deviation, mean of positive pixels, entropy, skewness were statistically associated with the potentially malignant group (P ≤ 0.0015 each). Sensitivity, specificity, positive predictive value, negative predictive value, and area under curve of RF model was 0.67, 0.91, 0.75, 0.88, 0.88; of LR model was 0.63, 0.93, 0.78, 0.86, 0.90, and of SVM model was 0.56, 0.91, 0.71, 0.84, 0.89, respectively. CONCLUSION: Three CT texture-based machine learning algorithms demonstrated high discriminatory capability in distinguishing benign from potentially malignant cystic renal masses as defined by the Bosniak Classification version 2019. If validated, CT texture-based machine learning algorithms may help reduce interreader variability when applying the Bosniak classification.

Molecular targeted therapy in gynaecologic malignancies: primer for radiologists.

The identification of characteristic genetic alteration in gynaecological malignancies has opened the door for molecular targeted therapy. The purpose of this review is to provide a primer for the radiologist on these agents with emphasis on the role of imaging in treatment response assessment and drug toxicities. The use of targeted therapy in gynaecological malignancies will likely increase in the future and make the role of the radiologist critical in response assessment and detection of toxicities.

Multimodality imaging of osseous involvement In haematological malignancies.

The purpose of this article is to provide a comprehensive review of the imaging features of osseous involvement in haematological malignancies. Osseous involvement can be seen in various haematological malignancies including lymphomas, plasma cell neoplasms, leukaemias and myeloproliferative neoplasms. Imaging plays a crucial role in initial diagnosis, staging and in the assessment of treatment response in these patients.