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Collaboration Delivers an Unusual Diagnosis

In a recent Case in PointCase of the Month, radiology and pathology converge to diagnose a rare tumor.

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Case in Point™ actively encourages its contributors to provide so-called zebra cases: diagnoses both rare and interesting. A recent Case of the Month meets these criteria while highlighting an essential component of radiology — cross-departmental collaboration.

A 58-year-old woman with a history of breast cancer, Li-Fraumeni syndrome, and a gastric bypass presented with abdominal fullness during a physical examination. Following imaging, a mass was detected, and a biopsy was ordered.

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“I think Case in Point is used by so many because it has an engaging, convenient, and efficient way of conveying valuable and practical information.” - Omar D. Katib, MD

Soon after, Omar D. Katib, MD, a radiology resident, Christopher P. Hartley, MD, a pathology resident, and Parag P. Tolat, MD, an assistant professor, all from the Medical College of Wisconsin in Milwaukee, came to a singular diagnosis in the case of an unusually located tumor.

The diagnosis was an omental myelolipoma, a benign tumor composed of mature adipose cells and hematopoietic tissue. “I was lucky enough to assist in the biopsy for this case, and I had never seen anything like it,” Katib says. “I was surprised by the pathology results and became more interested the more I read about [this kind of ] tumor, especially after learning how rarely it presents at that location.”

The reported incidence rate for myelolipoma is less than 1 percent on autopsy. An omental myelolipoma, however, is even rarer than a standard myelolipoma, with less than five cases reported in medical literature. Due to the composition of the tumor, radiologic diagnosis can be difficult. Other types of tumors appear similar in imaging, and diagnosis hinges on histologic composition. Histology demonstrates mature adipose cells intermixed with normal trilineage haematopoietic cells in various states of maturation.

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As a regular Case in Point user, Katib submitted the case for publication because “there [wasn’t] a case exactly like it in the archives, and it needed to be shared,” he recalls. “I think Case in Point is used by so many because it has an engaging, convenient, and efficient way of conveying valuable and practical information.”

The unusual location for the mass provided an excellent learning opportunity about types of abdominal masses, but also demonstrated the complementary roles of radiology and pathology. “I learned how imaging can help depict the composition of a mass,” Katib says, “and that the imaging appearance really can correlate with pathology at the microscopic level.”

Surgery is not considered necessary for asymptomatic myelolipomas. However, the patient in this case underwent surgery to alleviate discomfort.

For more than a decade, Case in Point has been a popular source of free CME for members, delivering valuable clinical education in the form of unique presentations of common and rare maladies. Case of the Month selections are determined based on reader feedback and editor review.

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See the complete case at

Earn Daily CME Credits!

Have radiology on the brain? Of course you do. Put your mind to good use with the daily Case in Point™ program, which gives you the opportunity each weekday to work through a subspecialty case developed by a community of residents, their mentors, and others. Plus, ACR physician members can earn free CME. Credits awarded for this activity are designated SA-CME by the American Board of Radiology and qualify toward fulfilling requirements for Maintenance of Certification Part II: Lifelong Learning and Self-Assessment. Follow  to receive new cases delivered straight to your inbox every weekday.

To submit a case, visit and be sure to review the archives for presentations of similar cases at To read about other Case of the Month winners, visit

By Chad Hudnall, senior writer, ACR Press

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