Current and upcoming radionuclide therapies in the direction of precision oncology: A narrative review.

As new molecular tracers are identified to target specific receptors, tissue, and tumor types, opportunities arise for the development of both diagnostic tracers and their therapeutic counterparts, termed "theranostics." While diagnostic tracers utilize positron emitters or gamma-emitting radionuclides, their theranostic counterparts are typically bound to beta and alpha emitters, which can deliver specific and localized radiation to targets with minimal collateral damage to uninvolved surrounding structures. This is an exciting time in molecular imaging and therapy and a step towards personalized and precise medicine in which patients who were either without treatment options or not candidates for other therapies now have expanded options, with tangible data showing improved outcomes. This manuscript explores the current state of theranostics, providing background, treatment specifics, and toxicities, and discusses future potential trends.

Imaging features of toxicities associated with immune checkpoint inhibitors.

The past decade has witnessed a change in landscape of cancer management with the advent of precision oncology. Immune checkpoint inhibitors (ICIs) have revolutionized cancer treatment and have played an important role in improving patient survival. While the patients are living longer, treatment with ICIs are sometimes associated with adverse effects, some of which could be fatal. Radiologists can play a crucial role by early identification of some of these adverse effects during restaging scans. Our paper focuses on the imaging features of commonly occurring ICI toxicities based on organ system.

Importance of tumor subtypes in cancer imaging.

Cancer therapy has evolved from being broadly directed towards tumor types, to highly specific treatment protocols that target individual molecular subtypes of tumors. With the ever-increasing data on imaging characteristics of tumor subtypes and advancements in imaging techniques, it is now often possible for radiologists to differentiate tumor subtypes on imaging. Armed with this knowledge, radiologists may be able to provide specific information that can obviate the need for invasive methods to identify tumor subtypes. Different tumor subtypes also differ in their patterns of metastatic spread. Awareness of these differences can direct radiologists to relevant anatomical sites to screen for early metastases that may otherwise be difficult to detect during cursory inspection. Likewise, this knowledge will help radiologists to interpret indeterminate findings in a more specific manner.

Imaging response assessment for oncology: An algorithmic approach.

Treatment response assessment by imaging plays a vital role in evaluating changes in solid tumors during oncology therapeutic clinical trials. Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 is the reference standard imaging response criteria and provides details regarding image acquisition, image interpretation and categorical response classification. While RECIST 1.1 is applied for the majority of clinical trials in solid tumors, other criteria and modifications have been introduced when RECIST 1.1 outcomes may be incomplete. Available criteria beyond RECIST 1.1 can be explored in an algorithmic fashion dependent on imaging modality, tumor type and method of treatment. Positron Emission Tomography Response Criteria in Solid Tumors (PERCIST) is available for use with PET/CT. Modifications to RECIST 1.1 can be tumor specific, including mRECIST for hepatocellular carcinoma and mesothelioma. Choi criteria for gastrointestinal stromal tumors incorporate tumor density with alterations to categorical response thresholds. Prostate Cancer Working Group 3 (PCWG3) imaging criteria combine RECIST 1.1 findings with those of bone scans. In addition, multiple response criteria have been created to address atypical imaging responses in immunotherapy.

Interventional oncology update.

Interventional Oncology (IO) is a subspecialty field of Interventional Radiology bridging between diagnostic radiology and the clinical oncology team, addressing the diagnosis and treatment of cancer. There have been many exciting advancements in the field of IO in recent years; far too many to cover in a single paper. To give each topic sufficient attention, we have limited the scope of this review article to four topics which we feel have the potential to drastically change how cancer is treated managed in the immediate future.

Teaching cancer imaging in the era of precision medicine: Looking at the big picture.

The role of imaging in cancer diagnosis and treatment has evolved at the same rapid pace as cancer management. Over the last twenty years, with the advancement of technology, oncology has become a multidisciplinary field that allows for researchers and clinicians not only to create individualized treatment options for cancer patients, but also to evaluate patients' response to therapy with increasing precision. Familiarity with these concepts is a requisite for current and future radiologists, as cancer imaging studies represent a significant and growing component of any radiology practice, from tertiary cancer centers to community hospitals. In this review we provide the framework to teach cancer imaging in the era of genomic oncology. After reading this article, readers should be able to illustrate the basics cancer genomics, modern cancer genomics, to summarize the types of systemic oncologic therapies available, their patterns of response and their adverse events, to discuss the role of imaging in oncologic clinical trials and the role of tumor response criteria and to display the future directions of oncologic imaging.

S184: preoperative sarcopenia is associated with worse short-term outcomes following transanal total mesorectal excision (TaTME) for rectal cancer.

INTRODUCTION: Malnutrition and deconditioning impact postoperative morbidity and mortality. Computed tomography (CT) body composition variables are used as markers of nutritional status and sarcopenia. The objective of this study is to evaluate the impact of sarcopenia, using CT variables, on postoperative outcomes following transanal total mesorectal excision (TaTME) for rectal cancer. METHODS: This was an institutional retrospective cohort analysis of consecutive rectal cancer patients who underwent TaTME between April 2014 and May 2020. Psoas muscle index (PMI) was calculated from diagnostic CT scans. Based on previous studies, patients in the lowest PMI tertile by gender were considered sarcopenic. Fisher's exact and Mann-Whitney U test were used to compare categorical and continuous variables, respectively. Readmission rates and postoperative complications were compared between groups. Backward stepwise logistic regression was used to determine the association between sarcopenia and 30-day postoperative complications. RESULTS: 85 patients were analyzed, of which 63% were male, with a median age of 59 (IQR: 51-65), and median BMI of 28 (IQR: 24-32). Of the entire cohort, 34% (n = 29) were sarcopenic (median PMI 5.39 IQR: 4.49-6.71). No significant difference in baseline characteristics between sarcopenic and nonsarcopenic patients were observed. 55% of sarcopenic patients experienced a complication within 30 days compared to 24% of nonsarcopenic patients (p = 0.01). 41% of sarcopenic patients required hospital readmission within 30 days compared to 17% of their nonsarcopenic counterparts (p = 0.014). Sarcopenic patients also experienced significantly higher rates of post-operative small bowel obstruction (10% vs. 0%, p = 0.04). Multivariable analyses identified that sarcopenic patients have a fourfold increase in odds of experiencing a 30-day postoperative complication (OR: 4.44, 95%CI: 1.6-12.4, p < 0.05) after adjusting for gender. CONCLUSION: Preoperative sarcopenia is associated with increased 30-day postoperative complications following TaTME for rectal cancer. Postoperative complications can have serious oncologic implications by delaying adjuvant chemotherapy. Therefore, preoperative recognition of sarcopenia prior to undergoing TaTME for rectal cancer may provide an opportunity for early intervention with prehabilitation programs.

Coordination and optimization of FDG PET/CT and COVID-19 vaccination; Lessons learned in the early stages of mass vaccination.

As the world embarks on mass vaccination for COVID-19, we are beginning to encounter unintended dilemmas in imaging oncology patients; particularly with regards to FDG PET/CT. In some cases, vaccine-related lymphadenopathy and FDG uptake on PET/CT can mimic cancer and lead to confounding imaging results. These cases where findings overlap with cancer pose a significant dilemma for diagnostic purposes, follow-up, and management leading to possible treatment delays, unnecessary repeat imaging and sampling, and patient anxiety. These cases can largely be avoided by optimal coordination between vaccination and planned imaging as well as preemptive selection of vaccine administration site. This coordination hinges on patient, oncologist, and radiologists' awareness of this issue and collaboration. Through close communication and patient education, we believe this will eliminate significant challenges for our oncology patients as we strive to end this pandemic.

COVID-19 Vaccination-Related Uptake on FDG PET/CT: An Emerging Dilemma and Suggestions for Management.

As mass COVID-19 vaccination is underway, radiologists are encountering transient FDG uptake in normal or enlarged axillary, supraclavicular, and cervical lymph nodes after ipsilateral deltoid vaccination. This phenomenon may confound interpretation in patients with cancer undergoing FDG PET/CT. In this article, we present our institutional approach for management of COVID-19 vaccine-related lymphadenopathy on FDG PET/CT according to early experience. We suggest performing PET/CT at least 2 weeks after vaccination in patients with a cancer for which interpretation is anticipated to be potentially impacted by the vaccination but optimally 4-6 weeks after vaccination given increased immunogenicity of mRNA vaccines and potentially longer time for resolution than lymphadenopathy after other vaccines. PET/CT should not be delayed when clinically indicated to be performed sooner. Details regarding vaccination should be collected at the time of PET/CT to facilitate interpretation. Follow-up recommendations for postvaccination lymphadenopathy are provided, considering the lymph node's morphology and likely clinical relevance. Consideration should be given to administering the vaccine in the arm contralateral to a unilateral cancer to avoid confounding FDG uptake on the side of cancer. Our preliminary experience and suggested institutional approach should guide radiologists in management of patients with cancer undergoing PET/CT after COVID-19 vaccination.

COVID-19 and its Mimics: What the Radiologist Needs to Know.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current outbreak of Coronavirus disease 2019 (COVID-19). Although imaging should not be used for first-line screening or diagnosis, radiologists need to be aware of its imaging features, and those of common conditions that may mimic COVID-19 pneumonia. In this Pictorial Essay, we review frequently encountered conditions with imaging features that overlap with those that are typical of COVID-19 (including other viral pneumonias, chronic eosinophilic pneumonia, and organizing pneumonia), and those with features that are indeterminate for COVID-19 (including hypersensitivity pneumonitis, pneumocystis pneumonia, diffuse alveolar hemorrhage, pulmonary edema, and pulmonary alveolar proteinosis).

The rates of second lung cancers and the survival of surgically-resected second primary lung cancers in patients undergoing resection of an initial primary lung cancer.

BACKGROUND: The Lung Cancer Screening Trial demonstrated improved overall survival (OS) and lung cancer specific survival (LCSS), likely due to finding early-stage NSCLC. The purpose of our investigation is to evaluate whether long-term surveillance strategies (4+ years after surgical resection of the initial lung cancer(1LC)) would be beneficial in NSCLC patients by assessing the rates of second lung cancers(2LC) and the OS/LCSS in patients undergoing definitive surgery in 1LC as compared to 2LC (>48 months after 1LC) populations. METHODS: SEER13/18 database was reviewed for patients during 1998-2013. Log-rank tests were used to determine the OS/LCSS differences between the 1LC and 2LC in the entire surgical group(EG) and in those having an early-stage resectable tumors (ESR, tumors <4 cm, node negative). Joinpoint analysis was used to determine rates of second cancers 4-10 year after 1LC using SEER-9 during years 1985-2014. RESULTS: The rate of 2LCs was significantly less than all other second cancers until 2001 when the incidence of 2LCs increased sharply and became significantly greater than all other second cancers in females starting in year 2005 and in men starting in year 2010. OS/LCSS, adjusted for propensity score by using inverse probability weighting, demonstrated similar OS, but worse LCSS for 2LCs in the EG, but similar OS/LCSSs in the ESR group. CONCLUSION: Because the rate of 2LCs are increasing and because the OS/LCSS of the 1LC and 2LC are similar in early-stage lesions, we feel that continued surveillance of patients in order to find early-stage disease may be beneficial.

The Incidence of Node-Positive Non-small-Cell Lung Cancer Undergoing Sublobar Resection and the Role of Radiation in Its Management.

Purpose: To identify the incidence, preoperative risk factors, and prognosis associated with pathologically positive lymph node (pN+) in patients undergoing a sub-lobar resection (SLR). Methods: This is a retrospective study using the National Cancer Database (NCDB) from 2004 to 2014 analyzing SLR excluding those with any preoperative chemotherapy and/or radiation, follow-up <3 months, stage IV disease, or >1 tumor nodule. Multivariable modeling (MVA) was used to determine factors associated with overall survival (OS). Propensity score matching (PSM) was used to determine preoperative risk factors for pN+ in patients having at least one node examined to assess radiation's effect on OS in those patients with pN+ and to determine whether SLR was associated with inferior OS as compared to lobectomy for each nodal stage. Results: A total of 40,202 patients underwent SLR, but only 58.3% had one lymph node examined. Then, 2,615 individuals had pN+ which decreased progressively from 15.1% in 2004 to 8.9% in 2014 (N1, from 6.3 to 3.0%, and N2, from 8.4 to 5.9%). A lower risk of pN+ was noted for squamous cell carcinomas, bronchioloalveolar adenocarcinoma (BAC), adenocarcinomas, and right upper lobe locations. In the pN+ group, OS was worse without chemotherapy or radiation. Radiation was associated with a strong trend for OS in the entire pN+ group (p = 0.0647) which was largely due to the effects on those having N2 disease (p = 0.009) or R1 resections (p = 0.03), but not N1 involvement (p = 0.87). PSM noted that SLR was associated with an inferior OS as compared to lobectomy by nodal stage in the overall patient population and even for those with tumors <2 cm. Conclusion: pN+ incidence in SLRs has decreased over time. SLR was associated with inferior OS as compared to lobectomy by nodal stage. Radiation appears to improve the OS in patients undergoing SLR with pN+, especially in those with N2 nodal involvement and/or positive margins.

Still Coming Out of the Dark: Enduring Effects of Simulation-Based Communication Skills Training for Radiology Residents-Four-Year Follow-Up.

PURPOSE: To evaluate the long-term efficacy of simulation-based communication skills training for radiology residents. METHOD AND MATERIALS: The simulation-based communication skills training curriculum was developed in 2014. The curriculum included a teaching module based on the essential elements of communication. Two sets of 6 communication scenarios encountered by radiologist were created. First and fourth year radiology residents reviewed the teaching module and completed the 6 simulated scenarios. They then underwent debriefing sessions, received faculty and staff evaluations. Four years later, the former first year residents (now fourth years) reviewed the teaching module again and repeated the simulation. They again underwent debriefing sessions after the simulation. This time the residents' communication skills were evaluated by faculty and staff. RESULTS: A total of 5 residents participated in this simulation-based skills training. The resident performance 4 years after initial training show not only that residents maintained their improved scores, but also that their scores improved further as compared to after the initial training. The average overall score for all but 1 resident increased at the 4 year follow-up simulation. From 2014 to 2018, the average score of all the residents increased from 72.4% to 81.4%. Comparison of the average scores of each student across 6 stations from 2014 to 2018 showed a statistically significant difference between the scores after 4 years (P = 0.014). CONCLUSIONS: Simulation-based communication skills training is effective and long lasting.

Pancreaticobiliary Trauma: A Multimodality Imaging Update.

Pancreaticobiliary injury is an uncommon entity which more often occurs in the setting of blunt than penetrating trauma. We present cases of pancreaticobiliary traumatic injuries from our Level 1 trauma center to illustrate an imaging update on the spectrum of injuries and correlation with current grading systems.