Clinicopathological review of 46 primary retroperitoneal tumors

Abstract

Objectives:To clarify the clinical factors including diagnostic imaging findings that may correlate with the histopathological malignancy in primary retroperitoneal tumors. Methods:The clinical backgrounds and imaging findings of 22 benign and 24 malignant primary retroperitoneal tumors were retrospectively investigated , and the prognosis of patients with malignant retroperitoneal tumors was assessed. Results: There were significant correlations between the presence of symptoms and malignancy (P < 0.01), as well as between the irregularity of tumor margins and malignancy (P < 0.01). On dynamic magnetic resonance imaging (MRI), 90% of malignant tumors showed early enhancement either with quick or slow washout, while 75% of benign tumors showed delayed and no enhancement (P < 0.002). All malignant and benign paraganglioma showed the same early enhancement with quick washout. Malignant lymphoma showed various enhancement patterns. The 2-year and 5-year cause-specific survival rates of the patients with malignant retroperitoneal tumors were 68.0% and 43.2%, respectively. All malignant lymphoma patients were mainly treated with chemotherapy after being diagnosed histologically. Malignant paraganglioma patients who could not meet complete resection needed chemotherapy for promising survival. Conclusion:The symptoms, the irregularity of the margins, and the specific enhancement pattern on the dynamic MRI may be important predictive factors of the primary malignant retroperitoneal tumors. Histological diagnosis was needed for malignant definition of paraganglioma because both benign and malignant paraganglioma showed similar clinical and imaging findings. Preoperative biopsy should be considered for selection of the appropriate treatment particularly in patients that are likely to have malignant lymphoma that could not be diagnosed definitively by the clinical and imaging findings.

Giant retroperitoneal bronchogenic cyst mimicking a cystic teratoma: A case report

“…The cysts are lined by a pseudostratified ciliated columnar epithelium, in addition to bronchial glands, smooth muscle cells or cartilage (3,5). Bronchogenic cysts commonly occur in the mediastinal region of the thorax, and are occasionally located in subcutaneous tissue, the pericardium, the spinal canal and other areas of the body (1).…”

“…However, with the development of radiological techniques, the number of incidental discoveries of asymptomatic RBC is rapidly increasing (5).…”

“…Despite their unique histological composition, RBCs are often misdiagnosed as teratomas, pseudomyxoma peritonei, lymphocoeles, hemorrhagic cysts, or neoplasms derived from the pancreas, adrenal system or urinary system (4). According to a previous study (5), the appearance of the aforementioned diseases are similar to RBCs on radiological imaging. Thus, at present, only histopathological examination is able to determine a definitive diagnosis of RBC.…”

Non-Hodgkin's lymphoma with uncommon clinical manifestations: A case report

“…As the symptom of renal colic was increasing, it was speculated that there was a high possibility of renal involvement. It is known that the most effective treatment is surgical removal of the tumors, with the exception of chemosensitive tumors, and that a definitive diagnosis can usually be made from the surgical specimens (12). Thus, considering the patient's wishes, surgery was performed.…”

“…The absence of MRI is a limitation in our diagnostic process. In the study of Tambo et al (12), a clinicopathological review of 46 primary retroperitoneal tumors identified that MRI imaging diagnosis prior to surgery was compatible with the histological diagnosis in only 26 patients (57%), and all six malignant lymphoma patients underwent biopsy or surgical resection. Therefore, if clinical diagnosis cannot be determined by MRI, definitive histological diagnosis by biopsy or tumor resection is required in order to determine the appropriate treatment.…”