Greater imaging utilization has increased the prevalence of incidental findings or incidentalomas, but unclear clinical context and guidelines complicate management. Accordingly, these authors offer a thorough review of the literature and discuss new opportunities for improving interdisciplinary management strategies.
Incidental findings, or incidentalomas, are coincidental imaging findings in an asymptomatic patient or findings in a symptomatic patient undergoing imaging for an unrelated reason. With higher imaging utilization and improved imaging resolution, the prevalence and burden of incidentalomas are rising.1 Management of incidentalomas is frequently challenging because of uncertain or absent classification systems. Poor patient communication often complicates the situation, resulting in under- or overdiagnosis. These factors could increase clinical practice errors and raise legal liability.
Due to the heterogeneity of imaging modalities and disease processes, the prevalence of incidentalomas is highly variable. A 2018 umbrella review revealed that CT chest incidentalomas (including CT cardiac, thorax, abdomen, spine, and heart) are the most prevalent at 45 percent, followed by CT colonography (38 percent), cardiac MRI (34 percent), and MRI of the brain (22 percent) and spine (22 percent).2 Conversely, incidentalomas found on CT chest for pulmonary embolism (2 percent) and whole-body PET/CT (< 2 percent) were the least prevalent.2
Although most incidentalomas are not an immediate danger to patients, some findings, such as neoplasms, may have a significant impact on one’s health. Malignancy rates vary substantially between organs. Breast incidentalomas reportedly have the highest malignancy rates at 42 percent.2 Renal, thyroid, and ovarian incidentalomas were malignant in greater than 25 percent of cases while extra-colonic, prostatic, and colonic incidentalomas were malignant 10 to 20 percent of the time.2 Brain, parotid, and adrenal glands had the lowest malignancy rates at less than 5 percent.2
Unsurprisingly, incidentalomas have become a challenging clinical issue for radiologists, referring providers, and patients. Adherence and follow-up have ranged from 36 to 67 percent depending on patient population, availability of guidelines, clinical settings, and system-level communication.3-5
Accordingly, let us take a closer look at avenues for improvement and examples of strategies to improve the management of incidentalomas.
Addressing Communication Concerns About Incidentalomas
It is uncommon for radiologists to communicate directly with patients regarding their results as patients often receive instructions from their primary care physicians (PCPs) or the ordering physicians.6 However, Zafar and colleagues found that PCPs were unlikely to act on incidentalomas without "explicit radiologist recommendations" if they had no prior experience with the finding or if it occurred in an unusual clinical context.7 Surveys have shown that "clear and actionable follow-up recommendations" exist in only 52 percent of cases.6 As such, incidentalomas without specific recommendations may not receive adequate follow-up.
Specific and clear recommendations can also alleviate overdiagnosis. Ambiguity in reporting language has increased misunderstandings in referring providers and patients. In Rosenkrantz's study, descriptions such as "statically likely to be a cyst," “too small to characterize," or "most likely a cyst" were all associated with less than 1 percent perceived likelihood of malignancy by radiologists but resulted in up to 46 percent follow-up by the referring physician.8 Rather than qualitative recommendations, radiologists could provide a numerical risk estimate to minimize ambiguity in their reports. The increased clarity would prevent patient misunderstandings and alleviate anxiety.
The American College of Radiology (ACR) Incidental Findings Committee has published white papers outlining imaging and clinical criteria for follow-up of incidentalomas and has made them readily available for use.9 Radiologists may use these guidelines to improve potential areas of ambiguity in their reports and direct referring physicians to evidence-based management.
However, no guidelines exist for incidentalomas in the spine, breast, brain, colon, prostate, or parotid glands.2 In those cases, specific evidence-based recommendations may be challenging. Furthermore, risk assessment for some incidentalomas is not possible without further imaging. For example, liver lesions on single-phase CT require additional imaging to characterize the lesions, and multiple co-morbidities in the patient could further complicate the read.10 The incidentalomas should trigger an interdisciplinary conversation between the radiologist and the referring provider.
While the radiologist provides expertise on the image findings, the referring provider can provide clinical context via history, physical examination, and previous treatments because the clinical context may be challenging for radiologists to ascertain. The benefit of interdisciplinary collaboration would extend to the patients as it prevents discordant treatment and follow-up plans, minimizing patient confusion and alleviating anxiety.
While more precise reporting would improve incidentaloma follow-up, patients could still fall through the cracks. The Joint Commission identified timely reporting of critical tests and diagnostic procedures as part of the National Patient Safety Goals in 2005.11 In practice, however, implementation has been inconsistent. Surveys have shown that in institutions with policy guidelines requiring closed-loop communication, actual compliance with these guidelines occurred 26 percent of the time.6 Clinical effectiveness outcomes looking for rates of treatment, diagnosis, and clinical outcomes are limited so there is potential for a large number of incidentalomas going undetected.12
Emphasizing Closed-Loop Communications and System-Level Changes
Closed-loop communication requires close interdisciplinary collaboration. Multiple studies have attempted to evaluate intervention strategies that improve follow-up, and those that demonstrate the highest levels of improvement utilized system-level interventions.12 After reviewing these study findings, we have categorized three central communication nodes as common intervention points and discuss the available methods to improve incidentaloma follow-up.
Communication Node 1: Radiology Team to Clinical Team
The radiologist has reviewed the index imaging study and is now relaying the information to referring provider. Due to the 21st Century Cures Act, which was signed into law on December 13, 2016, the patient can also view the radiology report. In this communication node, the radiologist has the most expertise. The purpose of this communication node is to accurately convey findings and recommendation guidelines to the clinical care team.
Several studies have demonstrated improved adherence and management when evidence-based guidelines are readily available to radiologists. After Zygmont and colleagues created a 16-page electronic summary guideline for the emergency department (ED), the correct management of ultrasound and CT incidentalomas improved from 67.5 percent to 80.2 percent.13 Interestingly, the team did not teach radiologists guideline content but rather informed the radiologists on the importance of following guidelines. The ease of accessibility was sufficient to yield improvement in management.
Similarly, Kim et al. found that adherence for society recommendations on follow-up imaging of ovarian cysts increased from 50 percent to 80 percent after integrating electronic guidelines.14 The availability of guidelines for references eliminated potential confusion when recommending follow-up. The integration of guidelines into dictation devices would serve to optimize workflow.
However, providing electronic guidelines to radiologists without sufficient referring clinician involvement did not demonstrate a statistically significant increase in adherence.14 A potential solution without significant workflow disruption would be creating a guideline-based radiology report. In a preliminary study, Woloshin and colleagues utilized an "enhanced report" to include clinician management strategies for pulmonary nodules. Eighty-eight percent of the surveyed clinicians strongly preferred the enhanced report, and 75 percent felt that the information gave them more confidence in management.15 While the utility of the "enhanced report" has not yet been tested in clinical practice, the study demonstrates a proof of concept that would enhance communication between the radiologist and the referring clinician.
Communication Node 2: Clinical Team to Patient
Once the information has been accurately relayed, the clinical care team would inform patients about the results, educate them on treatment options, and coordinate follow-up plans. The radiologist plays a more supportive role while the clinical team takes on the primary responsibility to ensure a shared-decision plan.
The type of clinical team plays an influential role in incidentaloma follow-up. Outpatients had the highest follow-up at 66.7 percent, followed by the emergency department (ED) patients at 46.0 percent and inpatients at 36.0 percent.5 Among outpatient physicians, PCPs were most likely to follow up at 67 percent, followed by internal medicine at 50 percent and surgery at 38 percent.5 The results are unsurprising. Outpatient PCPs and internal medicine physicians are comfortable with the longitudinal management of patients whereas surgeons are more likely to be focused on surgical issues. Patients who arrive at the ED may not have regular PCPs in the institution, contributing to lower follow-up rates.
Therefore, closed-loop communication would be essential to ensure that clinicians adequately adhere to evidence-based guidelines for follow-up. Shelver and colleagues utilized a lung nodule registry that interacted with the electronic health record (EHR) to ensure tracking completion.16 If tracking is indicated for the patient, support staff will activate an EHR alert until the referring physician addresses the incidentaloma. After the implementation of the tracking system, patients who were lost to follow-up or received delayed care decreased from 74 percent pre-intervention to 10 percent post-intervention.16
Baccei and colleagues implemented a similar alert system in the ED with positive effects.17 If an incidentaloma was discovered, the radiologist selected a checkbox labeled "incidental ED findings," which would route a report directly to the ordering ED physician's email. The alert would prompt the ED physician to converse with the patient or family regarding the findings. With additional optimization, the researchers noted a greater than 93 percent compliance rate in the study.17 The dramatic improvement after implementation demonstrates the value of closing the communication loop.
Communication Node 3: Health System to Patient
Once the patients have been informed of the incidentalomas and understand the following steps, the health system must actively ensure appropriate follow-up. The support staff becomes a significant part of the communication node as time progresses beyond the index imaging and patient discussion.
The support staff role is particularly vital when physicians do not receive the radiology report prior to patient discharge, such as in the ED. Baccei and colleagues created a "safety net" that used an Outlook e-mail inbox to track incidentalomas.17 A dedicated follow-up team monitored the inbox for incidentalomas to ensure that the ED provider had completed the workflow. The radiology report was also faxed to the patient's primary care provider if one was listed in the EHR. Furthermore, phone messages and certified mail requesting a call back serve as additional protection in preventing losses through follow-up.17
In a separate study, Wandtke and colleagues took a similar approach.18 They re-sent the radiology report, called the PCP’s office, and sent a letter to the patient if follow-up was incomplete. These interventions increased the examination completion rate from 43.1 percent to 70.5 percent. This follow-up tracking system may be even more vital for ED patients, inpatients, and surgical patients who are more likely to be lost to follow-up.
Successful intervention strategies to appropriately address incidentalomas will likely involve system-level changes. The identified communication nodes serve as targets for intervention. Differences in institutional resources and workflow likely prohibit a universal solution. Therefore, early interdisciplinary involvement in designing and executing interventions would minimize misunderstandings in intervention strategies.
Managing incidentalomas presents both a challenge and an opportunity. Their increased prevalence, complicated by unclear clinical context, has the possibility of leading to critical safety errors without sufficient follow-up. At the same time, there is also a risk of overtreatment for incidentalomas, and this causes undue anxiety for patients.
However, the situation creates the opportunity to improve interdisciplinary care. When radiologists make guideline-directed recommendations, referring clinicians can become more knowledgeable in managing incidentalomas, and radiologists can receive feedback to optimize their reporting and minimize ambiguity. It also opens a discussion between different disciplines on management strategies when there are separate medical society guidelines.
When there are incidentalomas without clear guidelines, close patient follow-up would provide us with the opportunity to better characterize the disease. Despite the current challenges, interventions like the ones mentioned above have shown dramatic improvements in patient follow-up and appropriate management and have the potential to become best practices across image modalities and practice settings.
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14. Kim DC, Bennett GL, Somberg M, et al. A multidisciplinary approach to using appropriate follow-up imaging of ovarian cysts: a quality improvement initiative. J Am Coll Radiol. 2016; 13(5):535-41.
15. Woloshin S, Schwartz LM, Dann E, Black WC. Using radiology reports to encourage evidence-based practice in the evaluation of small, incidentally detected pulmonary nodules. A preliminary study. Ann Am Thorac Soc. 2014;11(2):211-4.
16. Shelver J, Wendt CH, McClure M, et al. Effect of an automated tracking registry on the rate of tracking failure in incidental pulmonary nodules. J Am Coll Radiol. 2017;14(6):773-777.
17. Baccei SJ, Chinai SA, Reznek M, Henderson S, Reynolds K, Brush DE. System-level process change improves communication and follow-up for emergency department patients with incidental radiology findings. J Am Coll Radiol. 2018;15(4):639-647.
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