Inflammatory pseudotumor of the liver treated by hepatic resection: a case report

Inflammatory pseudotumor (IPT) of the liver is rare benign tumor. When the diagnosis of IPT is established with biopsy, simple observation or conservative therapy is preferred because of the possibility of regression. But IPT is unresponsive to the conservative treatment, surgical resection should be considered. We experienced a 63-year-old male, who was suspected hepatocellular carcinoma in abdominal computed tomography (CT) and magnetic resonance image (MRI) scan, presented with 2-month history of intermittent fever and weight loss. Percutaneous ultrasound guided core biopsy confirmed IPT of the liver. Non-steroidal anti-inflammatory drugs and antibiotics were administered for 8 and 4 weeks, respectively, but fever continued. So, extended right hepatectomy was performed for IPT of the liver and then fever subsided. The patient remains well during a follow-up period of 12 months.     

Inflammatory myofibroblastic tumor (inflammatory pseudotumor) of the breast

Inflammatory myofibroblastic tumor of the lung has often been reported but extrapulmonary cases are rare. Here we describe a case of inflammatory myofibroblastic tumor of the breast in a 60-year-old woman. This is only the eleventh case reported in the English language literature. The patient was free of disease 85 months after surgery.     

Inflammatory myofibroblastic tumor of the central nervous system and its relationship to inflammatory pseudotumor

Inflammatory myofibroblastic tumor (IMT) is a distinctive spindle cell lesion and occurs primarily in soft tissue. Recent evidence suggests a neoplastic nature, although historically, both neoplastic and nonneoplastic processes were combined in this category. Originally described as a nonneoplastic process, the term inflammatory pseudotumor (IP) has been used synonymously with IMT. IMTs have been linked to ALK gene (2p23) rearrangements, and some have suggested an association with the human herpesvirus 8 (HHV-8). IMT in the central nervous system (CNS) is rare, its characteristics are poorly defined, and its relation to similar tumors at other sites is unclear. To better characterize IMT within the CNS, we studied clinicopathologic features of 6 IMTs and compared them with 18 nonneoplastic lesions originally classified as IP. The IMT group consisted of 2 male and 4 female patients with a median age of 29 years. Of the six IMTs, 5 occurred within the cerebral hemispheres, and one was in the posterior fossa. All tumors were composed of neoplastic spindle cells and a variable amount of inflammatory infiltrate. Eighteen IPs included in this study consisted of predominantly inflammatory masses occasionally seen in the setting of systemic diseases. Only 1 IMT and none of the IPs recurred during the follow-up period. Four IMTs had either ALK protein overexpression or 2p23 rearrangement, and 1 case demonstrated both. None of the IPs were positive for ALK. Neither IMT nor IP cases demonstrated HHV-8 expression. We suggest that IMT in the CNS is distinct from the nonneoplastic IP, and distinguishing IMT from nonneoplastic lesions should enable better decisions for patient management.     

肝脏炎性假瘤与炎性假瘤样滤泡树突状细胞肿瘤的病理学诊断

目的探讨肝脏炎性假瘤及肝脏炎性假瘤样滤泡树突状细胞肿瘤的临床病理学特征及诊断、鉴别诊断要点。方法对肝脏炎性假瘤及肝脏炎性假瘤样滤泡树突状细胞肿瘤各1例进行临床病理分析、免疫组织化学染色及EBV-encoded RNA（EBER）原位杂交检测。结果肝脏炎性假瘤的临床症状包括右上腹不适或疼痛、发热、肝肿大、体重减轻等。大体肿瘤呈实性,境界清楚;镜下肿瘤细胞呈梭形,波浪状排列,其间可见大量淋巴细胞及浆细胞浸润以及散在分布的大的多形性细胞。核仁明显。肝脏炎性假瘤样树突状细胞肿瘤的临床症状、影像学表现及镜下表现均与肝脏炎性假瘤十分相似。但肿瘤细胞边界不清,胞质嗜酸性,除R—S样细胞外,还可见到不少形态怪异的巨细胞,且免疫表型CD21、CD35阳性。EBER（EBV—encoded RNA原位杂交）阳性。结论肝脏炎性假瘤样滤泡树突状细胞肿瘤是罕见的肿瘤,诊断时需注意与肝脏梭形细胞肿瘤甚至霍奇金淋巴瘤鉴别,树突状细胞免疫标记CD21、CD35阳性,特别是EBER原位杂交阳性有助于诊断。     

Post-traumatic inflammatory pseudotumor of the breast with atypical morphological features: A potential diagnostic pitfall. Report of a case and a critical review of the literature

Although inflammatory pseudotumor (IPT) and inflammatory myofibroblastic tumor (IMT) may share a common morphology, they are distinct clinico-pathologic entities. Unfortunately, the terms IMT and IPT are still used interchangeably, especially when lesions occur in unusual sites, including breast. All the cases of IMT/IPT involving the breast have raised spontaneously without any apparent prior injury. We herein report the first case of a post-traumatic IPT of the breast parenchyma in a 22-year-old male. Histologically, the lesion was highly cellular and composed of spindle cells arranged in a predominant fascicular pattern. Notably, mono- or multi-nucleated large pleomorphic cells were observed. Inflammatory cells, especially plasma cells and lymphocytes, were closely admixed with the spindle cell proliferation. The overall picture was reminiscent of an “IMT with atypical features”, typically seen in lung, abdomen, pelvis, and retroperitoneum of children. Immunohistochemically, the spindle-shaped and large pleomorphic cells were immunoreactive to vimentin, α-smooth muscle actin, and desmin. No immunoreactivity was obtained with ALK-1 protein. The present case contributes to widening the morphological spectrum of IPT of the breast, emphasizing the possibility that a reactive lesion may contain large pleomorphic cells that may represent a potential diagnostic pitfall. Lastly, we suggest that the diagnosis of IMT of the breast should be rendered with caution when dealing with ALK-negative spindle cell lesions in adult patients, and alternative diagnoses, including IPT, should be seriously considered.     

Inflammatory pseudotumor of the liver associated with malignant disease: report of two cases and a review of the literature

Two cases of inflammatory pseudotumor (IPT) of the liver associated with gastrointestinal tract cancer are reported. In addition, the etiological correlation between IPT and abscesses of the liver in cancer patients is discussed. The first patient was a 63-year-old woman who underwent distal gastrectomy and partial hepatectomy under a diagnosis of stomach cancer with liver metastasis. The second patient was a 66-year-old man who had undergone surgery for rectal cancer 6 years previously and underwent partial hepatectomy under a diagnosis of metastasis of rectal cancer to the liver. The gastric cancer was a papillary adenocarcinoma limited to the mucosa, and the rectal cancer was a moderately differentiated adenocarcinoma limited to the subserosa. The resected liver tumor in the first case measured 5.5×5.0×4.0 cm and was 2.5×1.9×1.6 cm in the second. The cut surface showed that both masses were well circumscribed and divided into lobules by fibrous tissue. They were yellowish white in color and there was no evidence of necrosis or hemorrhage. Histologically the masses consisted of fibrous areas and cellular areas, and the cellular areas consisted of fascicles of plump spindle cells mingled with varying numbers of plasma cells, lymphocytes, and histiocytes. The masses were diagnosed as IPTs. Obliterating phlebitis suggesting infection via the portal vein was seen in the adjacent liver tissue in both cases. According to previous cases reported in the literature, there are three types of cancers associated with hepatic IPT: gastrointestinal tract cancer, biliary tract cancer, and cancers that need strong systemic chemotherapy. The underlying cancer types of IPT of the liver are almost similar to those associated with pyogenic liver abscesses suggesting the etiological correlation between IPT and abscesses of the liver.     

Hepatic angiomyolipoma: a series of six cases with emphasis on pathological-radiological correlations and unusual variants diagnosed by core needle biopsy

Hepatic angiomyolipoma is rare and may pose differential diagnostic difficulty, particularly if encountered in core needle biopsy. We studied 6 cases from 5 males and one female (median age, 48.6 yrs). All presented with non-specific symptoms or an incidentally discovered tumor mass. Two patients had a remote history of chemotherapy for hematological neoplasms (acute lymphoblastic leukemia and Hodgkin lymphoma respectively) and another had clear cell renal cell carcinoma and anaplastic pancreatic carcinoma diagnosed at autopsy without definable syndrome. None of the patients had evidence of the tuberous sclerosis complex or renal or other extra-renal angiomyolipoma. Three tumors were resected completely and three have been only biopsied and followed up. None of the resected cases recurred at a mean follow-up of 35 months. Histologically, tumors were classified as classical triphasic (1), lipomatous (2), epithelioid/oncocytoid (1), epithelioid trabecular (1) and myelolipoma-like (1). The adjacent liver parenchyma was normal in 3 cases, showed pigment cirrhosis in one case and mild fatty change in another case. One case had clinically diagnosed but histologically unverified cirrhosis. The initial diagnostic impression/frozen section was misleading in 5 of the cases and included vascular lesion, focal fatty change, myelolipoma, hepatocellular tumor and oncocytic neoplasm. All tumors expressed HMB45 and variably desmin. One epithelioid lesion expressed HMB45 and TFE3, but lacked desmin expression. In conclusion, hepatic angiomyolipomas are increasingly recognized as incidental findings during surveillance for cirrhosis or investigations for unrelated conditions. Awareness of their diverse morphological spectrum in liver biopsy is necessary to avoid misdiagnosis as hepatocellular carcinoma, metastatic melanoma or other malignant neoplasms.     

Hepatic epithelioid angiomyolipoma with an unusual pathologic appearance: expanding the morphologic spectrum

Hepatic epithelioid angiomyolipoma (AML) is a rare lesion that is characteristically composed of a predominant or exclusive population of epithelioid cells coexpressing melanocytic and myogenic markers. The cystic variant of epithelioid AML is exceedingly uncommon. In this study, we present the clinicopathological features of a case of hepatic epithelioid AML with remarkable cystic degeneration in a 34-year-old female as well as with a literature review. A magnetic resonance imaging scan revealed a well-defined 30 cm × 25 cm hepatic mass. Sectioning of the well-defined mass revealed a non-encapsulated tumor that was multiloculated with amorphous necrotic tissue and hemorrhagic fluid. The inner cystic wall was rough and brownish-black in color. Microscopically, the tumor largely consisted of epithelioid cells that comprised approximately 95% of the total neoplastic components but also contained some spindle myoid cells, mature fat, and a thick-walled vasculature. Both intracellular and extracellular hyaline globules were frequently identified. Necrosis and invasive growth patterns were also present. By immunohistochemistry, spindle-epithelioid neoplastic cells were variably positive for Melan-A, HMB45, and SMA but were uniformly negative for epithelial and hepatocytic markers. This is the third report of a cystic AML in liver. The patient was followed for 71 months without any evidence of metastasis or recurrence.     

Malignant angiomyolipoma in the liver: a case report with pathological and molecular analysis

Malignant angiomyolipoma (AML) of the liver is rare. We report a case of AML with malignant transformation and metastases. A 30-year-old man had developed giant hepatic masses. Microscopically, the periphery of the tumor showed components of classic hepatic AML, but the central region contained atypical epithelioid components with extremely pleomorphic and hyperchromatic nuclei with frequent mitotic figures. Immunohistochemical analysis revealed that the epithelioid cells were positive for HMB-45 and smooth muscle actin. Furthermore, the atypical epithelioid cells displayed P53 immunoreactivity and mutation at exon 7 for p53. The tumor showed a typical monoclonal pattern but no loss of heterozygosity or microsatellite instability. Markedly atypical epithelioid cells with vascular invasion, distant metastasis, and fatal outcome were interpreted as malignant characteristics of hepatic AML. It is suggested that large tumor size, pleomorphic nuclei with high proliferation activity, and P53 immunoreactivity may predict the existence of malignant transformation of hepatic AML.     

Monotypic epithelioid angiomyolipoma of the liver

AIMS: Monotypic epithelioid angiomyolipoma is a recently recognized renal tumour, which is composed purely of epithelioid cells coexpressing markers of both smooth muscle differentiation and melanogenesis (HMB45). We report here the first case of monotypic epithelioid angiomyolipoma arising in the liver. CASE DETAILS: A 30-year-old woman without tuberous sclerosis complex (TSC) was incidentally found to have a hepatic mass by ultrasonography. Grossly, the resected tumour showed a nodule-in-nodule appearance, with large areas of haemorrhagic necrosis. Microscopically, the tumour was composed of pleomorphic epithelioid cells with clear, eosinophilic cytoplasm. Neither adipocytes nor abnormal vessels were recognized in the tumour. Immunohistochemically, the tumour cells were strongly positive for HMB45 and S100 protein, focally positive for desmin, vimentin and smooth muscle actin, and negative for epithelial markers (cytokeratins, EMA). Ultrastructural analysis showed numerous dense granules with some striated ones resembling melanosomes, myofilaments and pinocytic vesicles in the cytoplasm. Molecular analysis showed no allelic loss of the TSC2 region or 12 other chromosomal regions. The patient is free of disease over 1 year after the operation. CONCLUSION: We consider that this hepatic tumour is closely related to angiomyolipoma, and a counterpart of renal monotypic epithelioid angiomyolipoma.     

Uterine angiomyolipoma: case report and review of the literature

Extrarenal angiomyolipomas (AML) have been reported at various anatomical sites, but infrequently in the gynecological region. In the uterus, only a few cases have been described. We describe a uterine angiomyolipoma occurring in a 40-year-old woman without evidence of tuberous sclerosis. The tumor arose on the right wall of the uterine body and was partially cystic, and it was associated with marked degeneration. It was composed of mature adipose tissue, anomalous blood vessels and non-vascular smooth muscle cells. Immunohistochemistry revealed that non- vascular smooth muscle cells were positive for alpha-smooth muscle actin (alpha-SMA), desmin, vimentin, antihuman muscle actin (HHF35) and progesterone receptor (PR), and negative for cytokeratin, antihuman melanoma (HMB45), CD34, S-100 and estrogen receptor (ER). It is of particular interest that non-vascular smooth muscle cells were negative for HMB45, in contrast to renal and other extrarenal AML in which HMB45 immunoreactivity has been demonstrated in these cells.     

Clinicopathologic characteristics of inflammatory pseudotumor-like follicular dendritic cell sarcoma

Inflammatory pseudotumor (IPT)-like follicular dendritic cell (FDC) sarcoma is a recently described rare tumor and considered a unique entity, with different histologic appearances and behavior from those of the classical FDC sarcoma. This study analyzed the clinical and pathological findings of two such cases that the authors encountered and 36 previously reported cases identified in the literature. Assessment of all 38 cases showed a slight female predominance (2.2:1) with a median age of 56.5 years. Seventeen patients complained of abdominal discomfort or pain, while fifteen patients had no clinical symptom. Almost all cases occurred in liver (n = 20) or spleen (n = 17). Except in one case, all patients underwent surgical resection of the tumor alone. Histologic features showed a mixture of chronic inflammatory cells and variable amounts of spindle cells with vesicular nuclei and distinct nucleoli. The tumor cells expressed conventional FDC markers such as CD21 (75%), CD35 (92%), CD23 (62%), clusterin (75%), and CNA.42 (100%). EBV was detected in thirty-five cases (92.1%) by Epstein-Barr virus (EBV)-encoded RNA in situ hybridization, and EBV-latent membrane protein-1 was expressed in 90% of the cases. With a median follow-up of 21 months, 29 patients (85.3%) were alive and well, 4 (11.8%) were alive with disease, one patient (2.9%) died of disease. Only four patients with hepatic tumors underwent recurrence or metastasis after initial treatment. Epstein-Barr virus is thought to play a role in the development of the tumor; however, the pathogenesis of the disease and the origin of tumor cells remain unclear.     

Cytological features of inflammatory pseudotumor‐like follicular dendritic cell sarcoma of spleen: A case report

Here, we present the first cytological report of a primary splenic inflammatory pseudotumor‐like follicular dendritic cell sarcoma. The 57 year‐old male was incidentally found with a 2.2 cm well‐demarcated splenic nodule. A sonography guided fine needle aspiration of the lesion was performed. The cytologic smears revealed loosely cohesive fragments of oval to spindle cells in a background of prominent lymphoplasmacytic infiltration. The cells showed sparse chromatin, distinct nucleoli, syncytial cell borders, and occasional cytoplasmic processes. On the liquid‐based preparation, several histiocyte‐like cells with emperipolesis phenomenon were noted. Scant large atypical cells with prominent, cherry‐red nucleoli were found on the cell block sections. The initial cytologic interpretation was “atypical cells cannot exclude classical Hodgkin lymphoma.” The subsequent partial splenectomy showed an inflammatory pseudotumor‐like follicular dendritic cell sarcoma. The tumor cells were positive for CD21, CD35, smooth muscle actin, and EBER in situ hybridization. The cytologic differential diagnoses are briefly discussed. The knowledge of this rare entity, awareness of its cytomorphology, and proper ancillary tests would be helpful for correct cytologic diagnosis. Diagn. Cytopathol. 2017;45:230–234. © 2016 Wiley Periodicals, Inc.     

Hepatic angiomyolipoma. A case report with review of the literature

Hepatic angiomyolipoma in a 59-year-old woman is reported. The tumor was located at the lower edge of the left lobe of the liver, measured 3 x 2 x 2 cm, and appeared solid. Histologically, it consisted of abundant blood vessels of varying caliber, mature fat cells, and round, spindle-shaped or epithelioid interstitial cells. The latter were considered to be of smooth muscle origin, because myofilamentous structures were demonstrated ultrastructurally in the cytoplasm and because they were positive for desmin by the PAP method. Based on these findings, the diagnosis of angiomyolipoma was confirmed. A review of the literature revealed only 15 cases of hepatic angiomyolipoma. From a clinicopathological viewpoint, a comparison was made between hepatic angiomyolipoma and its more frequent renal counterpart. The hepatic tumor is considered to be a kind of hamartoma.     

Inflammatory myofibroblastic tumor with valvular involvement: a case report and review of the literature

BACKGROUND: Inflammatory myofibroblastic tumor (IMT) of the heart is extremely rare with unpredictable clinical expression. IMTs, characterized by spindle cells, plasma cells, and a polymorphic inflammatory infiltrate, have a predilection for children and young adults. Clinically, IMT mimics malignancy, making a definitive diagnosis difficult, prior to histopathological examination. METHODS AND RESULTS: We describe a case of an intracardiac IMT in a 69-year-old woman. Histopathological examination of excised specimens revealed a marked, polymorphic, infiltrate of lymphocytes and plasma cells. CONCLUSIONS: Cardiac IMTs are benign lesions with favorable prognosis. Herein, we present this case, along with a review of all cardiac IMTs published after the last review in 2002, with emphasis on clinical, pathologic, and immunohistochemical features.     

Monotypic epithelioid angiomyolipoma of the adrenal gland: an unusual site for a rare extrarenal tumor

Epithelioid angiomyolipoma (AML) is an uncommon renal mesenchymal tumor with malignant potential and is frequently associated with tuberous sclerosis. Extrarenal AMLs are rare, and to the best of our knowledge, this is the first reported case of a primary monotypic epithelioid AML of adrenal gland in a patient without evidence of tuberous sclerosis. The patient is a 42-year old man who presented with retroperitoneal hemorrhage resulting from spontaneous rupture of adrenal mass. Histologically, the tumor showed a prominent component of epithelioid smooth muscle cells with slightly pleomorphic nuclei, sometimes with prominent nucleoli and eosinophilic cytoplasm resembling oncocytic tumors. Epithelioid cells were positive for melanoma (HMB45 and positive MelanA) and smooth muscle markers (α-smooth muscle–specific actin), but not for epithelial markers (cytokeratin, EMA). Differential diagnosis from renal cell carcinoma, adrenal gland carcinoma, and metastatic carcinoma is often challenging because of its epithelioid morphology. Because primary and secondary malignant tumors are much more common and aggressive neoplasms, establishing the correct diagnosis has important therapeutic and prognostic implications.     

Transthoracic fine-needle aspiration cytology of inflammatory pseudotumor,fibrohistiocytic type: A case report with immunohistochemical studies

Inflammatory pseudotumor, fibrohistiocytic type, also called benign fibrous histiocytoma, is a rare reactive entity usually found incidentally on routine chest roentgenography. We present a case of inflammatory pseudotumor, fibrohistiocytic type, initially diagnosed by fine-needle aspiration (FNA) cytology in a 39-yr-old woman with a history of breast carcinoma. Cytomorphologic characteristics were confirmed by a cell block examination and immunohistochemical findings. The differential diagnoses of the fine-needle aspiration cytology of this type of inflammatory pseudotumor are discussed. Diagn. Cytopathol. 1998:19:216—220. © 1998 Wiley-Liss, Inc.     

Detection of Epstein–Barr virus-encoded small RNA-expressed myofibroblasts and IgG4-producing plasma cells in sclerosing angiomatoid nodular transformation of the spleen

Sclerosing angiomatoid nodular transformation (SANT) of the spleen is a rare inflammatory tumor-like lesion composed of vascular nodules and non-neoplastic stroma including spindle cells and inflammatory cells. The focus of our study was on the stromal proliferating process in SANT. Nine cases of SANT were examined. All cases showed alpha-smooth muscle actin (alpha-SMA) and vimentin on the spindle cells but not CD21, CD31, CD34, CD68, desmin, S100, human herpes virus-8, or anaplastic lymphoma kinase-1. In one case, 20-30% of the myofibroblasts in Epstein-Barr-virus (EBV)-positive spindle cells were detected using double-labeling immunohistochemistry for alpha-SMA and EBV-encoded small RNA in situ hybridization. A quantitative analysis of IgG and IgG4-positive plasma cells (pPCs) in SANT was performed. The median densities of IgG-pPCs and IgG4-pPCs in SANT were approximately four-fold and 13-fold higher than those in the normal spleens, respectively. In addition, there was a statistically significant increase of IgG4/IgG-pPCs ratio in SANT in comparison to the control specimens. In conclusion, the fibrogenesis in a subset of SANT may be associated with EBV-infected myofibroblasts in an overlapping immune reaction indicated by the presence of infiltrating IgG4-pPCs. Further investigation is needed to elucidate the association between SANT and IgG4-related sclerosing disease.     

Inflammatory pseudotumor (inflammatory myofibroblastic tumor) of the mitral valve of the heart

We report a rare case of inflammatory pseudotumor/inflammatory myofibroblastic tumor (IPT/IMT) of the heart, involving the mitral valve. A 58‐year‐old woman presenting with dyspnea was immediately admitted to the hospital, and found to have congestive heart failure due to the invagination of a tumor‐like mass of the mitral valve. This mass arose from and involved almost the entire posterior leaflet of the mitral valve and occupied almost the entire mitral valve orifice. The tumor was a yellowish‐white well‐circumscribed mass with a smooth surface. The excised mass was 3.0 × 2.3 × 1.8 cm, and consisted of abundant Sudan III‐positive foam cells, histiocytes, lymphocytes, plasma cells, and loosely arrayed spindle cells, in vascular‐rich fibrous tissue. Immunohistochemistry showed that the spindle cells were positive for vimentin and α‐smooth muscle actin, and negative for desmin, CD34, and human muscle actin (HHF‐35), suggesting they were myofibroblastic cells. The plasma cells and lymphocytes showed no monoclonality. There were few mitotic cells, and, except for the lymphocytes, few Ki‐67‐positive cells. The findings suggested IPT/IMT. The 39 cardiac IPT/IMT cases appearing in the English‐language literature are discussed.