Presentation of possible relapse in a patient with history of DLBCL: Classic imaging features of epiploic appendagitis

Our patient is a 59-year-old man with a history of diabetes and HIV infection. He also has diffuse large B-cell lymphoma, which was diagnosed after presenting with low back pain and having found a bulky left upper quadrant mass. He received etoposide, prednisone, vincristine, doxorubicin and cyclophosphamide (EPOCH) chemotherapy for six cycles followed by involved field radiation to the bulky retroperitoneal mass.

Six months later, the patient complained of a vague right neck pain. On examination, he was found to have a palpable firm fixed heterogeneous mass in right supraclavicular fossa. PET/CT scan showed a definite area of uptake at the lymphadenopathy, and biopsy revealed relapse of the non-Hodgkin’s lymphoma.

He received ifosfamide, etoposide, mitoxantrone and mesna (MINE) for six cycles with good response. He failed stem cell harvest, which prevented him from getting high-dose chemotherapy with stem cell transplant.

Two years later, he presented with anemia and thrombocytopenia with monocytosis: white count of 4,300/uL, monocyte of 56%, hemoglobin 9.6 g/dL and platelet of 39,000/uL.

Bone marrow biopsy revealed hypercellularity with bilinear dyspoiesis with 3% to 4% blasts; marked dyserythropoiesis and megakaryocytic atypia; left shift in myeloid lineage; no evidence of lymphoma, consistent with myelodysplastic syndrome.

One month later, he presented with left lower quadrant abdominal pain with a temperature of 99° F range. He denied night sweats, itching, change in bowel habits, nausea, vomiting or blood in the stools. Examination of the abdomen revealed a definite area of tenderness on palpation at the left lower quadrant medial to the left anterior iliac crest with an ill-defined linear mass-like area of firmness. PET/CT was done as recurrence of the lymphoma was suspected.

Figure 1. The soft tissue mass in the left abdomen on the current PET/CT scan (top row, green arrows CT, functional PET and fused images) in comparison to the most recent prior study performed six months earlier (bottom row, green arrows CT, functional PET and fused images). Corresponding functional images demonstrate mild heterogeneous FDG uptake that is not significantly changed. Courtesy of M Ghesani, MD

CT part of PET/CT showed a new focus of fat attenuation adjacent to the descending colon in the left lower quadrant with surrounding infiltration of the mesenteric fat, consistent with epiploic appendagitis. Functional images demonstrated mild FDG uptake.

Patient was given NSAIDs, and the inflammation resolved within a few days.

Discussion

Appendicitis epiploica, also termed as hemorrhagic epiploitis, epiplopericolitis, and epiploic appendagitis is a benign, self-limited inflammation of the epiploic appendages occurring secondary to torsion or spontaneous venous thrombosis of a draining vein.

Normal epiploic are peritoneal pouches arising from serosal surface of the colon; they are composed of adipose tissue and blood vessels. It is about 0.5 cm to 5 cm long, located near the sigmoid colon. It is visible on CT images only when inflamed or surrounded by fluid.

According to a study by Thomas and colleagues published in 1974, the possible causes for appendicitis epiploica are torsion and inflammation (73%), hernia incarceration (18%), intestinal obstruction (8%), or intraperitoneal loose body (<1%).

The median age of occurrence is between the fourth to fifth decades of life with a predominance in men. It presents as an acute left lower quadrant pain; with normal white count and temperature.

The usual sites affected are sigmoid colon, descending colon and right hemicolon in order of decreasing frequency. It often mimics acute abdomen as acute omental infarction, mesenteric panniculitis, fat-containing tumor, acute inflammatory processes in the large bowel (eg, diverticulitis, appendicitis) and primary tumor/metastases involving mesocolon.

CT scan will show an oval lesion 1.5 cm to 3.5 cm in diameter, with attenuation similar to fat and with surrounding inflammatory changes that abuts the anterior sigmoid colon wall.

Figure 2. Selected images of the left lower quadrant of the abdomen from the current PET/CT exam with CT, functional PET and fused images demonstrating a focus of fat attenuation with a surrounding halo of fatty infiltration and infiltration of the surrounding mesenteric fat (arrows), consistent with epiploic appendagitis, not seen on the prior examination. Functional images demonstrate mild FDG uptake, which can be seen with acute inflammation. Courtesy of M Ghesani, MD

Management is mainly conservative with NSAID for pain control. It spontaneously resolves in less than 10 days.

Malignancy was very high on our suspicion when our patient presented for the third time with pain and a mass. We should always keep broad differential diagnoses, and awareness of epiploic appendagitis mimicking acute abdomen will lead to proper medical management and thus avoid unnecessary surgeries.

Irene Dy, MD, is a Fellow in Hematology and Oncology at St Luke’s-Roosevelt Hospital Center.

Iwao Tanaka, MD, is a Resident in Radiology at St.Luke’s-Roosevelt Medical Center.

Gabriel Sara, MD, is in the Division of Hematology & Oncology at St Luke’s-Roosevelt Hospital Center and Assistant Clinical Professor of Medicine at the College of Physicians & Surgeons at Columbia University.

Deborah Rovner is a physician assistant to Dr. Sara.

Munir Ghesani, MD, is Associate Clinical Professor of Radiology at Columbia University College of Physicians and Surgeons and Attending Radiologist at St. Luke’s-Roosevelt Medical Center.