Incidental detection of rare mesenteric inflammatory pseudotumor by (18)F-FDG PET

Ultrasonic Manifestations of Mesenteric Inflammatory Myofibroblastic Tumors in Children

Objective: To explore the ultrasonic manifestations of mesenteric inflammatory myofibroblastic tumors (IMTs) in children. Methods: Seven patients with mesenteric IMTs were retrospectively analyzed. The ultrasonic manifestations, such as the locations, sizes, morphology, borders, internal echo, blood flow, and metastasis, of the tumors were detected. Results: In all the seven pediatric patients, a solitary lesion was found for the mesenteric IMTs, including five cases in the ileocecal mesentery and two cases in the mesentery of ascending colon. All the single tumors were revealed as irregular hypoechoic masses with uneven internal echoes and enhanced echoes in the surrounding intestine and omentum. Internal blood flow signals were enriched in the tumors. The borders were clear in five cases and unclear in two cases. In addition, two cases had peritoneal effusion and one case had calcified plaques. In the follow-up studies, one of the seven IMT patients had malignant transformation, and one case was transferred to the pelvic cavity. Conclusion: Ultrasonic examination can clearly demonstrate the locations, sizes, morphology, borders, internal echo, blood flow as well as metastasis of the pediatric IMT of the mesentery, having an important clinical application value as an adjunct to computed tomography (CT).

Voluminous omental inflammatory myofibroblastic tumor in an elderly man: a case report and literature review

Inflammatory myofibroblastic tumor (IMT) is a rare neoplasm of intermediate biologic potential, with uncertain etiology. This tumor occurs primarily in the lung, but the tumor may affect any organ system. A 75-year-old male was evaluated for voluminous palpable high abdominal mass with continuous and moderately abdominal pain, associated with abdominal distension for the last two months. Abdominal computed tomography showed a large (32 × 29 × 15 cm) heterogeneously enhanced mass with well-defined margins. At surgery, the mass originated from the greater omentum was completely excised. Histologically the tumor was a mesenchymal neoplasm in smooth muscle differentiation and was characterized by spindle-cell proliferation with lymphocytes, plasma cells, and rare eosinophils. Immunohistochemically, the tumor cells were positive for vimentin and smooth muscle actin and negative for anaplastic lymphoma kinase. Complete surgical resection of IMTs remains the mainstay of treatment associated with a low rate of recurrence. Final diagnosis should be based on histopathological and immunohistochemical findings. Appropriate awareness should be exercised by surgeons to abdominal IMTs in combination with constitutional symptoms, abnormal hematologic findings, and radiological definition, to avoid misdiagnosed.

Inflammatory myofibroblastic tumours: a pictorial review

Objectives

To present the most important characteristics of inflammatory myofibroblastic tumours (IMTs) arising in different locations of the body with histological correlation.

Methods

To review the symptoms and main radiological findings of IMTs. On ultrasonography (US), these tumours can appear as hypoechoic or hyperechoic masses and a variable Doppler appearance with increased vascularity. Computed tomography (CT) and magnetic resonance (MR) are the most used imaging tools in their evaluation. On contrast-enhanced CT, IMTs can appear as homogeneous or heterogeneous lesions, with variable enhancement on delayed acquisitions due to fibrosis. These findings are also present on gadolinium contrast-enhanced MR. On T1-weighted and T2-weighted sequences, IMTs usually show low signal intensity reflecting also the presence of fibrotic tissue.

Results

To show the main clinical symptoms and radiological features of IMTs in different locations: head and neck, lung, genitourinary, hepatic, splenic, gastrointestinal tract, mesenteric, muskuloskeletal.

Conclusions

Although IMTs in some organs are not uncommon, they are not usually included in the differential diagnosis of masses. Their radiological features suggest malignant neoplasms, whereas they are not. Consequently, this is an underdiagnosed entity and only after an histological exam could a definitive diagnosis be achieved.

Teaching Points

• Their radiological features suggest malignant neoplasms, whereas they are not

• CT and MR imaging are the most used tools in their evaluation

• IMT is an underdiagnosed entity

• The definitive diagnosis is only after histological exam

Mesenteric inflammatory pseudotumor: a case report and comprehensive literature review

PURPOSE

This study aims to provide an overview of the literature on mesenteric/omental inflammatory pseudotumors (IPTs).

METHODOLOGY

We present a new case of mesenteric IPT. We also conducted a systematic search of the English-language medical literature using PubMed, Medline, Google, and Google Scholar related to mesenteric or omental IPTs. The following search terms were used in various combinations: inflammatory myofibroblastic tumor, IPT, mesentery, and omentum. The search included articles published in the English language between January, 1978 and April, 2014. Studies were excluded if the full text was unavailable or missing information prohibited comparisons.

RESULTS

A total of 30 reports concerning 36 patients with inflammatory pseudotumors meeting the aforementioned criteria were included. The patients were aged from 10 months to 68 years (mean, 19.98 ± 20.5 years); 12 were female (16.75 ± 16.97 years; range, 10 months to 68 years) and 24 were male (21.6 ± 21.9 years; range, 18 months to 63 years). Detailed clinical and pathologic characteristics of 36 patients with IPTs are provided in Table 1.

CONCLUSION

IPTs may be definitively diagnosed only by histopathological examination and are most effectively treated by resection with negative surgical borders. No consensus has yet been reached regarding when nonsurgical treatment options are most appropriate in management of these lesions. IPTs often recur locally, while distant metastases are very rare. Postoperative close surveillance is essential to detect recurrences early.