Ectopic hepatocellular carcinoma (HCC) is defined as HCC arising from hepatic parenchyma located in an extrahepatic organ or tissue without any communication with the mother liver. It is very rare and difficult to diagnose by imaging alone. We report a case of a rare ectopic HCC mimicking a right para-aortic retroperitoneal mass and present a review of the literature. It is about a 79-year-old female patient, who presented with a progressive enlarged right paraaortic retroperitoneal mass, thought first to be leiomyosarcoma of vena cava on imaging. Subsequently, high alpha-fetoprotein (AFP) level and biopsy allowed the diagnosis of primary extrahepatic hepatocellular carcinoma.

UNASSIGNED: Epithelioid angiomyolipoma (EAML), a subtype of angiomyolipoma, is distinct. It has a biologic behavior of borderline tumor, a malignant tendency, and a risk of metastasis and recurrence. Adrenal EAML is very rare. It is true that only six cases of adrenal EAML have been documented in the English-language literature.
UNASSIGNED: A 65-year-old man who underwent a laparoscopic left adrenalectomy in July 2022 has adrenal EAML and this is a case report about it. The mass was surrounded by abundant blood vessels and adherence with surround-tissue. Postoperative pathology of the tumor analysis revealed adrenal epithelioid vascular smooth muscle lipoma. The patient underwent left upper abdomen and lumbar pain in July 2022. The enhanced computed tomography (CT) scan of the abdomen showed markedly enhanced masses in and around the left adrenal gland. A second left laparoscopic adrenalectomy was performed under general anesthesia. Postoperative pathology showed two taupe nodules of left adrenal, maximum diameter 0.9 to 1.1 cm. The postoperative pathological diagnosis in combination with immunohistochemistry was EAML. The patient was discharged 10 days later with symptomatic treatment with low molecular heparin.
UNASSIGNED: Adrenal EAML has a biologic behavior of borderline tumor with malignant potential and a risk of distant metastasis and recurrence. Therefore, radical surgical resection should be considered as its necessary treatment. Long-term postoperative follow-up is an important part of the treatment.

Non-seminomatous germ cell tumors with structural components from all three cellular lineages are called teratomas. We report a rare case of a primary right adrenal teratoma in a postmenopausal female, presenting with abdominal pain. Ultrasound revealed a complex cystic shadow in the perihepatic region superior to the upper pole of the right kidney, which was suggestive of a complex supra-renal space-sequence-occupying lesion. Computerized tomography revealed a large-sized mature single multilobulated complex cystic lesion in the right hypochondrial lumbar region arising from the right adrenal gland. A right-sided transperitoneal adrenalectomy was performed. The resected mass (18 × 13 × 10 cm) was well encapsulated. Cut surfaces showed cystic mass filled with necrotic gray-white pultaceous material, along with a solid white gelatinous area. Microscopic sections showed a tumor which displayed differentiation along various tissue lineages. After immunohistochemical examinations, the tumor was confirmed to be a mature cystic teratoma. Mature teratomas show a good prognosis, and surgical resection and follow-up remain the standard approach.

Pulmonary sequestration is a congenital malformation of lung development in which part of the lung tissue is separated from the normal lung during the embryonic phase and develops separately and receives blood supply from an aberrant systemic artery forming a nonrespiratory mass. In brief, early in embryonic development, certain tissues that should have atrophied and been gradually absorbed are left behind due to impairment of the atrophy process and form anomalous branches of the aorta, which pull parts of the lung tissue, isolating them from normal lung tissue and bronchi, and thus forming separate lung tissue. According to the relationship of the mass to the pleural covering, pulmonary sequestration can be divided into two types, intralobar pulmonary sequestration (ILS) and extralobar pulmonary sequestration (ELS), of which approximately 75% of cases are ILS, but ELS is less common. Symptoms are not obvious in either type, making diagnosis and differential diagnosis more difficult. Here we report a 33-year-old patient with only insignificant abdominal distension who was eventually diagnosed with retroperitoneal ELS.

Primary retroperitoneal serous cyst adenomas (PRSCs) are extremely rare thin-walled cystic lesions whose pathogenesis is not well understood. Clinical presentation varies depending on the lesion\'s size and location, i.e., larger lesions compress adjacent organs, giving the impression of malignancy. Although advances in imaging techniques enable to identify various characteristics of retroperitoneal cystic lesions, there are no pathognomonic signs to confirm the diagnosis. The exact diagnosis is based on the histology after complete surgical excision. An open surgical approach is considered the traditional method of complete resection; however, laparoscopic techniques have increasingly been employed. Diagnostic aspiration is discouraged due to the potential risk of seeding if the lesion is malignant. We present the case of a 51-year-old woman who underwent complete excision of a large right retroperitoneal cyst, histologically confirmed as PRSC with a review of the background and management options of this phenomenon.

Retroperitoneal ganglioneuroma is a rare neuroectodermal tumor with a benign nature. We performed a literature review among 338 studies. We included 9 studies, whose patients underwent CT and/or MRI to characterize a retroperitoneal mass, which was confirmed to be a ganglioneuroma by histologic exam. The most common features of ganglioneuroma are considered to be a solid nature, oval/lobulated shape, and regular margins. The ganglioneuroma shows a progressive late enhancement on CT. On MRI it appears as a hypointense mass in T1W images and with a heterogeneous high-intensity in T2W. The MRI-\"whorled sign\" is described in the reviewed studies in about 80% of patients. The MRI characterization of a primitive retroperitoneal cystic mass should not exclude a cystic evolution from solid masses, and in the case of paravertebral location, the differential diagnosis algorithm should include the hypothesis of ganglioneuroma. In our case, the MRI features could have oriented towards a neurogenic nature, however, the predominantly cystic-fluid aspect and the considerable longitudinal non-invasive extension between retroperitoneal structures, misled us to a lymphatic malformation. In the literature, it is reported that the cystic presentation can be due to a degeneration of a well-known solid form while maintaining a benign character: the distinguishing malignity character is the revelation of immature cells on histological examination.

Leiomyomas are benign mesenchymal tumors which originate from smooth muscle cells. Extrauterine leiomyomas are rare and they may arise where smooth muscle cells are found. Their diagnosis is challenging due to their heterogeneous ways of presentation. Histological analysis may reveal areas of sarcomatous differentiation; therefore, complete resection of the entire tumor is the only curative treatment. There is no adjuvant therapy proved to increase overall survival. It is essential to develop a standardized protocol, detailing how to follow up these patients since it is not reported in the literature to date; however, it is advisable to follow them because the local recurrence rate is high if small implants remain. In this review, we present 3 cases of extrauterine leiomyomas diagnosed and treated in our hospital. The management was different in each case, highlighting the heterogeneity of this condition. According to the literature, there are no solid guidelines on their management. We compare our experience with the data available to date in order to support the existing knowledge and provide our expertise for future studies.

A malignant germ cell tumor (GCT) might contain or transform into malignant non-germ cell histology, commonly referred to as somatic-type malignancy (SM). It is a rare phenomenon with poorly understood pathogenesis. SMs are mostly associated with teratomas and are mainly observed in late relapsing cases. There are no consensus guidelines on the management of SMs; however, surgery is considered to be the mainstay of treatment. Prognosis is variable depending on the time of diagnosis, site of relapse, and type of histology. Here, we present a case of a 44-year-old male with a history of mixed GCT stage IIA, initially managed with right radical orchiectomy, who developed a relapse of GCT 10 years later with an SM of adenocarcinoma subtype.

A 17-year-old female presented to our hospital complaining of bloody diarrhea 4-6 times per day for the past month. She was a known case of inflammatory bowel disease noncompliant to her medications. Abdominal computed tomography revealed an unusually dilated mass in the retroperitoneum at L2 vertebral level connecting the lumbar and left renal veins. The renal artery was visualized separately, and a diagnosis of communicating vein varicosity was made. This lesion can be misleading on imaging, hence our aim to disseminate our findings to practicing radiologists. The differential diagnosis of these lesions include retroperitoneal lymphadenopathy, renal artery aneurysms, and testicular cancers causing retroperitoneal lymphadenopathy. To our knowledge, this is the first case to be reported in association with inflammatory bowel disease, perhaps providing a novel insight into the pathogenesis of this lesion that has not been considered in the contemporary literature.

Differential diagnosis of retroperitoneal masses may become complex and requires careful anamnesis, physical examination and several complementary tests. We present the clinical case of a male patient aged 45 years who was diagnosed with a 4cm paraaortic lesion compatible with neuroendocrine tumor in the abdominal computed tomography (CT) exam. The workup performed with SPECT-CT, somatostatin receptors scintigraphy, MIBG scintigraphy, 24-hour urine total and fractionated catecholamines and 24-hour urine 5-OH indoleacetic did not confirm the first diagnostic impression. Finally, the lesion was biopsied and presence of micro-organisms was revealed. Further exams confirmed schistosomiasis as the cause of the paraaortic lesion. Histological diagnosis can be helpful with regard to the differential diagnosis of retroperitoneal masses.