Dedifferentiated liposarcoma of the liver

Primary pleomorphic liposarcoma of the liver: a case report and literature review

Background

Primary liposarcoma arising from the liver is exceedingly rare. There have been very few reports documenting primary hepatic liposarcoma, especially of the pleomorphic subtype. Surgery is currently the only established treatment method, and the prognosis remains poor. In this report, we present an unusual case of hepatic liposarcoma of the pleomorphic subtype with literature review. In addition, we discuss theories regarding pathogenesis and the pathological and clinical features of primary hepatic liposarcoma to better outline this rare entity.

Case presentation

An asymptomatic 65-year-old female was found to have a right hepatic mass on a computed tomography scan 2 years after surgical resection of the left adrenal gland and kidney for adrenocortical carcinoma. Laboratory examinations were unremarkable. Magnetic resonance imaging demonstrated a 16-mm mass in the right hepatic lobe. Adrenocortical carcinoma metastasis was suspected. Laparoscopic partial hepatectomy completely removed the tumor with clear margins. Macroscopically, the surgical specimen contained a nodular, yellow–white mass lesion 20 mm in diameter. On pathologic examination, pleomorphic, spindle-shaped tumor cells containing hypochromatic, irregularly shaped nuclei of various sizes formed fascicular structures. Scattered lipoblasts intervened in varying stages. Mitotic cells were frequent. Ki-67 labeling index was 15%. Immunohistochemically, the tumor cells were diffusely positive for vimentin and focally positive for CD34 and alpha-SMA; lipoblasts were focally positive for S-100. Tumor cells were nonreactive for SF-1, inhibin alpha, desmin, HHF35, HMB45, Melan A, MITF, c-kit, DOG1, cytokeratin AE1/AE3, h-caldesmon, STAT6, CD68, MDM2, CDK4, c17, DHEAST, 3BHSD, CD31, Factor 8, and ERG. From these findings, primary hepatic liposarcoma of pleomorphic subtype was diagnosed. The tumor recurred intrahepatically 3 years later, and the patient died 5 months after recurrence.

Conclusions

In our report, we discussed the rarity, theories regarding pathogenesis, and a review of the literature of this atypical condition. To the best of our search, this is the 14th case of primary hepatic liposarcoma and the 2nd case of the pleomorphic subtype reported throughout the world. Further research regarding the etiology of this unusual clinical entity is warranted to establish effective diagnostic and management protocols.

Primary pleomorphic liver liposarcoma: A case series and literature review

Primary hepatic liposarcoma is an extremely rare mesenchymal tumor that accounts for only 0.1% to 2% of primary malignant liver tumors. Due to its rarity, there is a lack of knowledge about its clinical course, management, and prognosis. Only 15 cases of primary liposarcoma of the liver have been reported since 1973. Among these 15 cases, only two involved primary liver liposarcoma with a pleomorphic subtype. Here we report the third and fourth cases of primary pleomorphic liver liposarcoma. A 57-year-old female presented with abdominal discomfort and progressive abdominal distension for two weeks. Computed tomography (CT) of her abdomen revealed a large well-defined solid nodule mass with an area of necrosis and hemorrhage occupying segment IV-B of the liver. Wide local excision was performed. She had an uneventful recovery and remained well at six months post-treatment. A 65-year-old male presented with an abdominal mass for two-month. CT demonstrated a mass in the left lobe of the liver with mixed soft tissues and fat attenuation. He underwent wide local excision. He was discharged on day three postoperatively. Histological analysis for both cases revealed liposarcoma of the liver with a pleomorphic subtype.

Positron emission tomography/computed tomography manifestations of primary hepatic myxoid liposarcoma: A case report

RATIONALE

Computed tomography (CT) and magnetic resonance imaging (MRI) are conventional used to evaluate liver tumors. Detection of fat component is considered an important clue to the imaging diagnosis of hepatic myxoid liposarcoma. However, the positron emission tomography (PET)/CT report of hepatic myxoid liposarcoma is scarce, and the metabolic characteristics of primary hepatic myxoid liposarcoma are still unknown.

PATIENT CONCERNS

In this report, we report the PET/CT manifestations of a rare case of primary hepatic myxoid liposarcoma that was confirmed by pathologic examination. A 29-year-old male patient presented with a nodule adjacent to the umbilicus that had been present for 2 weeks. PET/CT showed a hypoattenuating mass with moderate uptake (maximum standardized uptake value [SUVmax] 1.9), except for a slightly hyperattenuating focal area with intense uptake (SUVmax 3.1).

DIAGNOSES

The final pathologic diagnosis was confirmed, by means of laparotomy, to be a primary hepatic myxoid liposarcoma with multiple extrahepatic metastases.

INTERVENTIONS

The lesions in the left liver and periumbilical abdominal wall were punctured. During the laparotomy, hepatic malignant tumors were confirmed and metastasized widely in the abdominal cavity.

OUTCOMES

An abdominal CT performed 4 months after initial presentation showed extensive metastasis.

LESSONS

Primary hepatic myxoid liposarcoma may manifest as moderate metabolism with less fat on PET/CT. PET/CT is not only valuable in reflecting the round cell component of hepatic myxoid liposarcoma, but also in estimating its origin.

Dedifferentiated retroperitoneal liposarcoma spontaneously occurring in an aged SD rat

Liposarcoma is a rare neoplasm in rats and is characterized by the presence of lipoblasts containing multiple cytoplasmic vacuoles. We encountered a rare type of liposarcoma in a male SD (Crj:CD(SD)IGS) rat during a long-term study to gather background data. At necropsy at 105 weeks of age, there was a large amount of fatty tissue covering the mesentery, pancreas, and retroperitoneum; a white nodule in the right kidney; and paleness of the liver. Microscopically, the tumor had a well-differentiated component and dedifferentiated high-grade component. Immunohistochemical and electron microscopic examinations revealed that the pleomorphic tumor cells retained the characteristics of lipoblasts. Distant or disseminated metastasis was also confirmed in various organs. A liposarcoma with these histological features is extremely rare in rats, and this is the first report of a highly metastatic dedifferentiated type of liposarcoma originating from the abdominal fat tissue in a rat.

Angiomyolipoma of the Liver

Angiomyolipoma, a rare benign liver tumor, was observed in a 50-year-old woman examined with US, CT, MR imaging and angiography. Dynamic studies using CT and MR imaging were valuable in differentiating the disease from hepatocellular carcinoma with fat deposits.

Primary pleomorphic liposarcoma of liver: a case report and review of the literature.Case Reports Hepatol. 2013;2013:398910. [PMID: 25374715 DOI: 10.1155/2013/398910]

Primary liver liposarcoma is a rare disease. The knowledge of the clinical course, management, and prognosis of primary liver liposarcoma are all limited because of its rarity. Twelve cases of primary liposarcoma of the liver have been previously reported. We present the thirteenth case, which occurred in an adult male patient. A 42-year-old male patient came to our outpatient department with complaints of pain abdomen, mass per abdomen, and weight loss. Ultrasonography showed a mass arising from the the left lobe of liver. CT abdomen showed a heterogenous enhancing mass from left lobe of liver with multiple cystic and necrotic areas compressing the stomach and spleen with no evidence of metastasis. Differential diagnosis included adenoma and primary malignancy. Exploratory laparotomy and resection were done. HPE was found to be pleomorphic liposarcoma of liver.

Liposomes targeting tumour stromal cells

Liposomes have found clinical application in cancer therapy in the delivery of cytostatic agents. As a result of the targeted delivery of these toxic molecules to the tumour cells coupled to avoidance of toxicity-sensitive tissues, the therapeutic window is widened. Over the past years the focus of cancer therapy has shifted towards the stromal cells that are present in the tumour. It appears that clinically relevant tumours have acquired the ability to modulate the microenvironment in such a way that a chronic pro-inflammatory and pro-angiogenic state is achieved that contributes to invasion and metastasis and continued proliferation. Over the past years, liposomal formulations have been designed that target key stromal cell types that contribute to tumour growth. At the same time, many promising cell types have not been targeted yet and most of the studies employ drugs that aim at depleting stromal cells rather than modulating their activity towards an anti-tumour phenotype. In this review these target cell types will be addressed. Complementing these targeted formulations with the appropriate drugs to optimally suppress tumour-promoting signals while preserving anti-tumour action will be the challenge for the future.

Primary liposarcoma of gallbladder diagnosed by preoperative imagings: A case report and review of literature

A 49-year-old Japanese woman was referred to our department because of high fever and a huge abdominal mass. Computed tomography (CT) and magnetic resonance (MR) imagings revealed a tumor, about 30 cm in diameter, occupied the right hepatic lobe and the peritoneal cavity. Abdominal angiography showed that the tumor was fed mainly by the cystic artery. We preoperatively diagnosed angiosarcoma of the gallbladder and performed tumor resection with cholecystectomy because the tumor was almost casplated, however the posterior wall of the gallbladder attached to the tumor firmly. Histologically, the tumor was composed of spindle cells including lipoblasts with cellular pleomorphism, which were also detected in the muscular layer of the gallbladder. We finally diagnosed pleomorphic liposarcoma of the gallbladder. At 10 mo and 29 mo after the first operation, she underwent two more operations because of recurrence. Now she has a good quality of life 3 years and 6 mo after the first operation.

A case of huge primary liposarcoma in the liver

Primary liver liposarcoma is a rare disease. Because of its rarity, the knowledge of the clinical course, management, and prognosis of primary liver liposarcoma are all limited for clinicians. A 61-year-old female patient who suffered from a huge primary liposarcoma in the central portion of the liver had the clinical presentations of fever, nausea, vomiting, jaundice, and body weight loss. The huge tumor was resected successfully. However, the tumor recurred repeatedly and she had repeated hepatectomies to remove the tumor. The tumor became aggravating after repeated surgeries. Eventually, the patient had cervical spinal metastasis of liposarcoma and she survived for 26 months after liver liposarcoma was diagnosed. Although the tumor may become aggrava-ting after repeated surgeries, repeated hepatectomies are still the best policy to achieve a long-term survival for the patients.

Malignant liver tumors

Primary malignant liver tumors can arise from different components of the liver, such as hepatocytes, bile duct epithelium, neuroendocrine cells, and mesenchymal cells. A specific diagnosis frequently can be suggested from imaging studies, but biopsy remains the gold standard for definitive diagnosis of liver tumors. Clinical history of chronic liver disease, known risk factors, or other diseases are of great importance. Patient's age is also an important discriminating feature because several tumors such as hepatoblastoma, mesenchymal hamartoma, and infantile hemangioendothelioma, are found predominantly in pediatric populations, whereas cholangiocarcinoma and hepatocellular carcinoma are rare in pediatric populations.

Primary liposarcoma of the liver: a case report and review of literature

Liposarcoma is a rare mesenchymal malignant tumor, which usually originates in the retroperitoneum and the extremities. Seven cases of primary liposarcoma of the liver have been previously reported. We present the eighth case, which occurred in an adult female patient. Primary liposarcoma of the liver, although extremely rare, must be considered in the differential diagnosis of a hepatic mass that develops in a noncirrhotic liver, especially in patients who are potential candidates for orthotopic liver transplantation. Liposarcoma is an absolute contraindication for liver transplantation.

Sonographic appearance of primary liver liposarcoma

Primary malignant mesenchymal tumors of the liver are extremely rare. We report a case of a primary liposarcoma in the right hepatic lobe of a 50-year-old man. Sonography showed a poorly defined, lobulated, infiltrating echogenic tumor with shadowing. Within the tumor were hyperechoic and hypoechoic foci thought to represent areas of hemorrhage and necrosis. Color Doppler sonography showed the mass to be avascular. A low-attenuation mass of fat density was confirmed on CT. The resected tumor was reasonably well circumscribed, with demonstrable infiltration of the liver parenchyma. Histologic analysis showed liposarcoma with high-grade sarcomatous features.

Hepatic angiomyolipoma: a clinicopathologic study of 30 cases and delineation of unusual morphologic variants

Hepatic angiomyolipoma (AML) is frequently misdiagnosed. HMB-45 is a promising immunomarker for this tumor that leads to recognition of some AMLs with unusual morphology. The purpose of this collaborative study is to better define the morphologic variations of AML. Thirty AMLs were examined, including four biopsy specimens and two fine-needle aspirates. The diagnosis was confirmed by the presence of HMB-45-positive myoid cells. Almost half the cases were originally misdiagnosed as carcinomas or sarcomas. There was marked female predominance (25:5), and the mean age was 48.7 years (range 29-68). Three patients (10%) had evidence of tuberous sclerosis and all had renal AML. According to the line of differentiation and predominance of tissue components, the tumors was subcategorized into mixed, lipomatous (> or = 70% fat), myomatous (< or = 10% fat), and angiomatous type. The mixed type was the most common (11 resected cases), comprising sheets of epithelioid muscle cells admixed with islands of adipocytes, abnormal vessels, and frequently, hematopoietic cells. Six tumors (including three from biopsy specimens) were heavily fatty and showed predominantly adipocytes with epithelioid and short spindle myoid cells webbed between fat cells. Of 10 myomatous AMLs, five tumors showed a pure sinusoidal trabecular pattern and comprised mainly epithelioid cells. Typically, mature adipocytes were absent or scanty, but fat was seen as fine droplets within cytoplasm or as occasional large globules in sinusoids. Pelioid and inflammatory pseudotumor-like patterns were identified focally. Regarding cellular features of the myoid cells, most of the epithelioid cells were either eosinophilic or clear with spiderweb cell morphology. Three AMLs showed an almost purely oncocytic appearance with scanty fat. Large pleomorphic epithelioid cells existed as small foci. Spindle cells arranged in long fascicles were uncommon. D-PAS-positive globules were common around pelioid areas. Brown pigments with staining characteristics of hemosiderin and/or melanin were noted. In conclusion, we propose HMB-45-positive myoid cells as the defining criterion of hepatic AML, which is a tumor capable of dual myomatous and lipomatous differentiation and melanogenesis. Because of its protean morphologic appearance, recognition of the various variant patterns and cell types is important for a correct diagnosis, assisted by immunohistochemical confirmation with HMB-45. Trabecular and oncocytic cell tumors appear to stand out as distinctive subtypes.

Primary hepatic osteosarcoma: case report and literature review

We describe a primary osteosarcoma of the liver in a 72 year old man. The man was symptomatic and had suffered abdominal pain and distension for four months before he died. At autopsy a large tumor of the liver with direct extension into adjacent structures was found. There was no evidence of primary tumor or primary bone lesion at any other site. Histologically, the tumor comprised malignant cells producing abundant osteoid arranged in a lace-like pattern. Smaller chondroblastic and fibroblastic components were also present. These findings were in keeping with a diagnosis of primary hepatic osteosarcoma.

Dedifferentiated liposarcoma with an inflammatory malignant fibrous histiocytoma-like component presenting a leukemoid reaction

A rare case of dedifferentiated liposarcoma (well-differentiated liposarcoma with an inflammatory malignant fibrous histiocytoma (MFH)-like anaplastic component) occurring in a 69-year-old male is presented. The patient had noticed a dull pain in his left loin and thigh for about 1 month. Computed tomography examination revealed a low-density mass lesion, measuring about 6 cm in diameter, in the left iliopsoas muscle, and it was surgically removed. Grossly, the lesion was composed of an encapsulated, soft, whitish mass and an adjacent, well-demarcated, yellowish hard nodule, measuring about 2.5 cm in diameter. Microscopically, both lesions showed features of an inflammatory variant of MFH and a sclerosing type of well-differentiated liposarcoma, respectively. To our knowledge, only two cases of dedifferentiated liposarcoma combined with inflammatory MFH as a dedifferentiated component have been recorded in the literature. The salient feature of the present case is a systemic inflammatory reaction, as shown by prominent leukocytosis (up to 73,900/mm3) and the elevated serum value of C reactive protein (up to 26.0 mg/dL), which were transiently reduced after surgery. The inflammatory reaction was suggested to be induced by cytokines, such as granulocyte colony-stimulating factor and interleukin-6, which were probably produced by the tumor cells in the present case, because the elevated serum values of those cytokines were decreased after surgery.

Hepatic neoformations

The aim of the paper is an accurate histologic description and illustration of those liver lesions that are usually summarized under the heading of "hepatic tumors and related subjects". For in some cases it may be unclear or at least controversial, whether the individual lesion is indeed an autonomous neoplasia or a malformation, regeneration or hyperplasia, the indifferent master term of neoformation is introduced, based on the fact that all of them are characterized by a cellular multiplication. According to common definitory practice the survey distinguishes between mesenchymal (angiomatous and non angiomatous) and epithelial neoformations. Among the latter hepatocellular and cholangiocellular types are distinguished, the criterium for differentiation being a phenomenological one, which is by no means identical with a histogenetical statement. The definition of subgroups mostly adheres to current nomenclatory usage; only occasionally--in the group of endothelial tumors--a novel term is employed, in view of brevity and coordination with the overall system of neoformations.

"Lipomatous" lesions of unknown cellular origin in the liver of B6C3F1 mice

The gross, microscopic, and ultrastructural features of lipomatous lesions in the liver of B6C3F1 mice are described. The cases were selected from a database of 45,406 male and 45,674 female mice used as treated, control, or vehicle-control animals in the National Cancer Institute's Bioassays or the National Toxicology Program's 2-year carcinogenicity studies. Thirteen hepatic lesions identified from cases within the database were re-evaluated microscopically and selected for further study. These lesions were present in ten males and three females that were between 85 and 113 weeks of age at the time of death. Grossly, the liver lesions were described as white to yellow or red to brown nodules/masses or foci that ranged from 2.0 to 25 mm in diameter. The lesions commonly involved the median and left lateral hepatic lobes. Microscopically, many of the lesions closely resembled lipomas described in the liver of human beings, and they consisted of nonencapsulated mature adipose-like tissue with irregular margins. The majority of the cells that comprised the lipomatous lesions were signet-ring shaped. These cells were positive for lipid as evidenced with oil red-O. The lipid droplets were also present within the hepatocytes that comprised the hepatic plates trapped within or surrounding many of the lipomatous lesions. At the margins of many of the lesions there were spindle-shaped cells that contained small intracytoplasmic lipid vacuoles. These cells were often within a stromal matrix that had focal areas of collagen and mucopolysaccharides, as evidenced by weak staining with Masson's trichrome and periodic acid-Schiff's stains, respectively. There was also disruption of the reticulum fibers in many of the lesions, as noted with a Gomori's reticulum stain. Ultrastructurally, cytoplasmic organelles, such as rough endoplasmic reticulum, free ribosomes and small lipid vacuoles, were present in the spindle-shaped cells, whereas signet-ring-shaped cells had few discernible organelles due to peripheral compression of the cytoplasm by single large vacuoles occupying the cytoplasmic space. The spindle-shaped cells were free of lysosomes. Thin collagen fibers were seen in contact with some of the spindle-shaped cells and were located between these cells and adjacent hepatocytes, or endothelial cells lining sinusoidal capillaries. A distinct basal lamina was not associated with spindle- or signet-ring-shaped cells. Similar lipomatous lesions were not found in other visceral organs. The exact cellular origin of the hepatic lesions described here is not known.

Osteosarcoma with features mimicking malignant fibrous histiocytoma

Three osteosarcomas (OS) with features resembling malignant fibrous histiocytoma (MFH) were selected and investigated to identify any clinico-pathological similarities. In all cases there was no significant difference from conventional OS on the radiography and laboratory data. The appearance of MFH-like features within the whole tumour tissue varied from 7% to 55%. It was composed of spindle-shaped cells arranged in short irregular fascicles and a storiform pattern admixed with osteoclast-like giant cells, but devoid of neoplastic osteoid. Such spindle-shaped cells had a poorly developed rough endoplasmic reticulum and expressed a strong alkaline phosphatase activity as well as vimentin. A series of allografts to athymic mice using the MFH-like tissues also showed histologically a proliferation of plump spindle-shaped cells with a storiform pattern lacking osteoclast-like giant cells, and intensely positive for alkaline phosphatase. These findings indicate that the MFH-like features are identified as modulated OS. The constituting cells are most likely to be poorly developed with possible phenotypic alteration in the maturation stage of osteoblastic cell lineage, but different from conventional MFH of bone as regards their distinct histochemical pattern.

Experimental rhabdomyosarcoma with regions like malignant fibrous histiocytoma (MFH)--a true double phenotypic pattern?

In murine sarcomas induced by 20-methylcholanthrene, histological features of malignant fibrous histiocytoma (MFH) as well as rhabdomyosarcoma were found in the same tumour both at light microscopy and at ultrastructural level. The areas showing rhabdomyomatous differentiation expressed vimentin, desmin, muscle-specific alpha-actinin, and sometimes myoglobin, but in the MFH areas only vimentin was expressed. A series of allografts in athymic mice, using tumour areas of both histological types, showed in every case a mixed pattern of tumour growth, whether the transplanted tissue was of MFH or rhabdomyosarcomatous type. This suggests that the MFH areas in the original experimental sarcomas were modulated disguised rhabdomyosarcomas. The significance of MFH-like areas in non-related soft tissue sarcomas is also discussed.