Paratesticular liposarcoma: coexistence with urinary bladder cancer

A 58-year-old man with liposarcoma originating from the right paratesticular area was reported. Histologically, liposarcoma showed a well-differentiated sclerosing type. Coexistence of transitional cell carcinoma of the urinary bladder and liposarcoma was also revealed. The cases of paratesticular liposarcoma in the literature are briefly reviewed.     

Paratesticular liposarcoma--a case report

A case of paratesticular liposarcoma in a 60 year male is presented for its rarity. The tumour was a dedifferentiated liposarcoma (DDL) seen in the original excision.     

Paratesticular myxoid liposarcoma: a case report

Liposarcoma of the paratesticular region is a rare malignant soft tissue neoplasm. Out of all the possible sites of liposarcoma, the incidence in spermatic cord is rare, accounting for only 5% of these neoplasms. Among the various subtypes of liposarcoma described in the paratesticular region, myxoid variant of liposarcoma is seen very rarely. One such case is we ported here for its rarity and also to draw attention to the fact that, early diagnosis and complete excision carry better prognostic value.     

Well-differentiated liposarcoma of the paratesticular area: report of a case with fine-needle aspiration preoperative diagnosis and review of the literature

This article presents a rare case of well-differentiated liposarcoma of the paratesticular area (spermatic cord) with a preoperative cytological diagnosis. A 0.6-mm fine-needle aspiration biopsy (FNAB) of a paratesticular lump showed many spindle and polygonal atypical cells with numerous cytoplasmic vacuoles. On the basis of a diagnosis of "malignant mesenchymal neoplasia consistent with liposarcoma," the patient underwent radical orchiectomy. A 8 x 7 x 8.5 cm, whitish mass was found, which was histologically classified as a "well-differentiated liposarcoma" (with lipoma-like, sclerosing, and myxoid areas), according to the classification of Enzinger and Weiss. A review of the literature is presented.     

Paratesticular myxoid/round cell liposarcoma harboring type 3 DDIT3-FUS fusion gene: Report of a very rare case

Myxoid/round cell liposarcomas are rare mesenchymal neoplasms. They preferentially occur in the lower extremity, and most of them have type 1 or type 2 DDIT3-FUS fusion gene. We report here a very rare case of myxoid/round cell liposarcoma of the paratesticular region with type 3 DDIT3-FUS fusion gene. A 46-year-old Japanese man noticed a gradually enlarged intrascrotal mass without pain. Surgical resection of 3.4 cm × 2.1 cm oval mass was carried out, and it was located in the right paratesticular region apart from the spermatic cord and epididymis. Histological examination of the tumor revealed ovoid cell proliferation with anastomosing vascular network and scattered lipoblasts. Genetic analysis elucidated that the tumor had a chromosomal translocation, type 3 DDIT3-FUS chimeric gene. The tumor was definitely diagnosed as myxoid/round cell liposarcoma of the paratesticular region.     

Paratesticular liposarcoma with smooth muscle differentiation mimicking angiomyolipoma

AIMS: To discuss the differential diagnosis of a case of well-differentiated liposarcoma which had areas resembling angiomyolipoma-a feature which, to our knowledge, has not been reported previously. METHODS AND RESULTS: A tumour in the paratesticular region had apparently been present for 40 years, but had grown recently. A fat component containing lipoblasts was admixed with areas resembling angiomyolipoma, i.e. desmin positive, but HMB45-negative smooth muscle proliferation with atypia and thick-walled blood vessels devoid of elastin. CONCLUSION: The diagnosis of liposarcoma, rather than angiomyolipoma with adipose atypia, in this case is based on the fact that smooth muscle differentiation is documented in liposarcoma, lack of HMB45 staining and recent clonality studies which suggest that the fat in angiomyolipoma is not neoplastic.     

Well-differentiated liposarcoma (atypical lipomatous tumors).

Well-differentiated (WD) liposarcoma accounts for about 40% to 45% of all liposarcomas therefore representing the larger subgroup of adipocytic malignancies. It tends to occur equally in the retroperitoneum or the limbs followed by the paratesticular area and the mediastinum, with a peak incidence between the fifth and the seventh decades. WD liposarcoma is further subdivided in the adipocytic (lipoma-like), sclerosing, inflammatory, and spindle cell subtypes, of which the first two are by far the commoner. WD adipocytic liposarcoma is composed of a relatively mature adipocytic proliferation, featuring cell size variation as well as at least focal nuclear atypia. A varying number (from many to none) of lipoblasts may be found. Sclerosing WD liposarcoma is characterized microscopically by the presence of scattered distinctive bizarre stromal cells and multivacuolated lipoblasts set in a fibrillary collagenous background. Inflammatory liposarcoma represents a rare variant of WD liposarcoma in which a chronic inflammatory infiltrate predominates to the extent that the differential diagnosis is mainly with nonadipocytic lesions such as inflammatory myofibroblastic tumor, Castleman's disease, and Hodgkin's as well as non-Hodgkin's lymphomas. Spindle cell liposarcoma is the rarest variant and is composed neural-like spindle cell proliferation set in a fibrous and/or myxoid background and associated with an atypical lipomatous component which usually includes lipoblasts. Cytogenetically, WD liposarcoma appears to be relatively homogenous exhibiting characteristic ring as well as giant marker chromosomes containing amplified genetic material derived from the 12q13-15 chromosome region. As WD liposarcomas of any type have no potential for metastasis unless they undergo dedifferentiation, the opportunity to replace the term "WD liposarcoma" with a less frightening denomination has produced a long, sharp debate. WD liposarcoma and atypical lipoma should be considered as synonyms and their use should therefore be determined by the degree of reciprocal comprehension between the surgeon and the pathologist to prevent either inadequate or excessive treatment.     

Lipid rich rhabdomyosarcoma.

A lipid rich rhabdomyosarcoma of the paratesticular region was studied by light microscopy, histochemistry, immunohistochemistry and electron microscopy. The tumour was composed of primitive looking, vacuolated, and pleomorphic cells. Lipid was present in varying amounts in all cells but was especially abundant in the vacuolated and pleomorphic cells. Some cells showed eosinophilic fibrillary cytoplasm but cross-striations were not seen. Tumour cells were positive for desmin, muscle specific actin, and vimentin. A few cells were myoglobin positive. At electron microscopy, the presence of lipid was confirmed, while thick and thin filaments, Z disks, lamina and glycogen were observed, thereby confirming striated muscle differentiation. Although moderate amounts of lipid can be expected in almost any tumour, lipid rich rhabdomyosarcomas have received little attention. The present report provides a comprehensively examined case of such a tumour initially presenting diagnostic difficulty because of its possible confusion with liposarcoma.     

Ultrastructural and histochemical identification of sclerosing liposarcoma

A paratesticular tumour by light microscopy showed large amounts of partly hyalinized collagenous stroma, spindle shaped fibroblast-like cells, pleomorphic cells with foamy cytoplasm, multinucleated tumour type giant cells and lipid inclusions. By light microscopy, there was a problem as to whether the tumour should be classified with the liposarcomas or with the fibrous histiocytic group. Ultrastructurally, spindle shaped cells resembled fibroblasts and, in a few cells, intracellular collagen fibres were seen. Histochemical studies revealed the presence of mannose-rich glycoprotein which is characteristic for collagen producing cells, but frequently these cells also showed numerous lipid inclusions. The foamy cytoplasmic areas of pleomorphic cells were shown to consist of dilated ergastoplasmic sacs and large vacuoles lined by smooth endoplasmic reticulum negating the possibility that these cells were of histiocytic origin. This is supported further by the dearth of lysosomes and absence of lysozyme (muramidase) in the tumour cells. The presence of numerous lipid inclusions in many of the tumour cells, which are otherwise ultrastructurally similar to fibroblasts, suggests that these cells represent precursors of lipoblasts. The above findings taken together allowed the tumour to be categorized as a sclerosing liposarcoma.     

Seltene Tumoren und tumorähnliche Läsionen des Hodens und der paratestikulären Region

Tumors and tumor-like lesions of the testes and paratesticular structures are rare neoplasms often documented solely in case reports but are morphologically similar to their counterparts in other organ systems. According to the World Health Organization (WHO) classification, miscellaneous tumors of the testis, tumors of collecting ducts and rete testis, tumors of paratesticular structures are differentiated from mesenchymal tumors of the spermatic cord and testicular adnexa. In the differential diagnostics of a space-occupying mass in the testis or paratesticular region, tumor-like lesions should be considered because these lesions represent a large collection pot and occur more often than was originally assumed.     

The paratesticular region: histoanatomic and general considerations

The paratesticular region includes the testicular collecting system, the testicular tunics, and spermatic cord. For the purpose of discussion in this issue, the rete testis is also considered part of the paratestis, although it is principally intratesticular in location. The embryologic origins of the paratesticular components and their detailed anatomic and histologic features are presented to provide a background to better understand the pathologic processes affecting the paratestis. A wide variety of cysts, hyperplasias, neoplasms, and tumor-like conditions may affect the paratesticular region, at times resulting in challenging problems in differential diagnosis. An approach to the paratesticular causes of an intrascrotal mass lesion is presented.     

Paratesticular solitary fibrous tumor: a case report and review of literature

Solitary fibrous tumor (SFT) is a rare spindle cell neoplasm that usually arising from the pleura, but has been reported in diverse extrapleural sites. Urogenital localization is rare, and only several cases of paratesticular SFT have been reported. In the present report, we present the case of a 61-year-old male suffering from a paratesticular SFT. A surgical excision of the lesion was performed. The tumor was well circumscribed and consisted of a mixture of bland spindle cells and dense collagen bands. Immunohistochemical studies showed positive reactivity for CD34, CD99 and vimentin, but stained negative for CD117, S100, SMA, HMB45, Desmin and CD68. All these clinicopathologic features are suggestive of the diagnosis of paratesticular SFT.     

Clear cell adenocarcinoma of the tunica vaginalis of the testis with an adjacent uterus-like tissue

Testicular and paratesticular neoplasms that resemble the common epithelial type of ovarian tumor are quite rare. Paratesticular clear cell carcinoma is very uncommon in the testis, with no reported cases of a tumor arising from the tunica vaginalis in the literature to our knowledge. The present case shows that it is highly malignant and metastatic. The differential diagnosis of the tumor was made after thorough clinical, pathological and immunohistochemical investigations, from the mesothelioma of the tunica vaginalis, paratesticular serous papillary carcinoma, carcinoma of the rete testis, epididymal adenocarcioma, yolk sac tumor of the testis and metastatic carcinoma. The tumor showed Bcl-2 and Her-2/neu immunoreactivity, but was non-reactive for p53. This tumor, with a uterus-like structure as a paratesticular tumor-like mass, was composed of endometrial-type glands and stroma surrounded by bundles of smooth muscle, and is the third example of this kind of structure in English written literature. The patient, having normal external genitalia and fertility, represents the first reported case of paratesticular malignant differentiation of müllerian-type epithelium in the normal gonadal state. Müllerian-type epithelium located in the vicinity of the testis and/or endometriotic metaplasia of the mesothelium of the tunica vaginalis might be the possible origins for this uterus-like structure, and as a result, for this tumor.     

Primary soft tissue tumors of the epididymis, paratesticular tissue and spermatic cord

The present study comprises 23 primary soft tissue tumors of the epididymis, paratesticular tissue and of the spermatic cord. These tumors were reclassified according to the diagnostic criteria of the WHO. The most common tumor of the paratesticular tissue is the adenomatoid tumor (65%), followed by the leiomyoma (17%). Other recognized tumors are: two typical lipomas, one lipo- and one leiomyosarcoma. Because of its relatively high frequency the adenomatoid tumor is reviewed more in detail with regard to its morphology and histogenesis. Some problems of the clinical pathology of paratesticular soft tissue tumors are briefly discussed.     

Pleomorphic liposarcoma: a clinicopathologic analysis of 19 cases.

Pleomorphic liposarcoma is a variant of liposarcoma defined morphologically by the presence of pleomorphic lipoblasts. Because of its rarity, there are limited studies with long-term follow-up information. Nineteen pleomorphic liposarcomas were studied. Unequivocal pleomorphic lipoblasts were required for inclusion. In each case, the following features were noted: tumor site; tumor size; tumor depth; predominant histologic pattern (epithelioid or malignant fibrous histiocytoma [MFH]-like); extent of necrosis (absent, less than 15%, or at least 15%); mitotic counts; treatment and clinical follow-up. Patients were 11 females and 8 males, aged 33-87 years (mean, 64.5 y; median, 70 y). Tumors involved the extremities (13 patients: intramuscular in 10, subcutaneous in 2, depth unknown in 1), retroperitoneum (4 patients), mediastinum (1 patient), and paratesticular region (1 patient). Size ranged from 4.5--31 cm (mean, 11.9 cm; median, 12.0 cm). Predominant pattern was epithelioid in 7 and MFH-like in 12. Necrosis was present in 15 (79%) and was extensive (36 15%) in 14 patients. Mitotic counts ranged from 0.2--3.4/10 high-power fields (mean, 1.4; median, 1.4) by the average-count method and from 1--6/10 high power fields by the highest count method (mean, 2.9; median, 3.0). All patients were treated surgically; 10 patients received adjuvant chemotherapy and/or radiation therapy. On follow-up of 18 patients (range, 2--129 mo; mean, 35.4 mo; median, 23 mo) nine (50%) were dead of disease (range, 2--48 mo; mean, 20.1 mo; median, 12 mo), one died of other causes 2 months after diagnosis, two were alive with disease, five were disease free, and one was alive at 129 months (tumor status unknown). Five had recurrences (range, 3--28 mo; mean, 14.4 mo; median, 8 mo), and four of five (80%) with recurrences were dead of disease. Metastases developed in eight patients (range, 4--48 mo; mean, 19.5 mo; median, 11.5 mo), most commonly to the lungs. In conclusion, pleomorphic liposarcoma is a rare tumor of adulthood that occurs most commonly in the deep, soft tissues of the extremities. It behaves as a high-grade sarcoma that frequently metastasizes, most commonly to the lungs. Although this tumor has a wide range of histologic appearances, no clinical or pathologic feature is predictive of a more aggressive clinical course.     

Primary retroperitoneal myxoid/round cell liposarcoma is a nonexisting disease: an immunohistochemical and molecular biological analysis

Almost all primary retroperitoneal liposarcomas can be classified as well-/dedifferentiated liposarcoma. Rarely, however, primary retroperitoneal liposarcoma is classified as myxoid/round cell liposarcoma, based on the presence of myxoid areas and vascular crow's feet pattern, which has resulted in a debate on the classification of liposarcoma in the retroperitoneum. Genetically, myxoid/round cell liposarcoma and well-/dedifferentiated liposarcoma are different diseases. Myxoid/round cell liposarcoma is characterized by a translocation causing FUS-CHOP or EWSR1-CHOP fusion, whereas well-/dedifferentiated liposarcoma is characterized by an amplification of the 12q13-15 region, including MDM2 and CDK4 genes. As myxoid/round cell liposarcoma is highly radio- and chemosensitive, differentiation between subtypes is important to optimize treatment. We studied whether primary retroperitoneal liposarcomas diagnosed as myxoid/round cell liposarcoma represent molecularly true myxoid/round cell liposarcoma or are histopathological mimics and represent well-/dedifferentiated liposarcoma. Primary retroperitoneal myxoid/round cell liposarcoma (n=16) were compared to primary extremity myxoid/round cell liposarcoma (n=20). Histopathological and immunohistochemical features were studied. Amplification status of the 12q13-15 region was studied using a multiplex ligation-dependent probe amplification analysis, and FUS-CHOP or EWS-CHOP translocations were studied using RT-PCR. In primary retroperitoneal myxoid/round cell liposarcoma, MDM2 and CDK4 staining was both positive in 12 of 15 cases. In primary extremity myxoid/round cell liposarcoma, MDM2 was negative in 18/20 and CDK4 was negative in all cases. Multiplex ligation-dependent probe amplification showed the amplification of 12q13-15 region in 16/16 primary retroperitoneal myxoid/round cell liposarcomas and in 1/20 primary extremity myxoid/round cell liposarcomas. Translocation was present in all (18/18) primary extremity myxoid/round cell liposarcomas, but absent in all primary retroperitoneal myxoid/round cell liposarcomas. On the basis of immunohistochemical and molecular characteristics, apparent primary retroperitoneal myxoid/round cell liposarcoma can be recognized as well-/dedifferentiated liposarcoma with morphological features mimicking myxoid/round cell liposarcoma. In these cases, treatment should probably be specifically designed as for well-/dedifferentiated liposarcoma. Moreover, finding of myxoid/round cell liposarcoma translocations in a retroperitoneal localization is highly suggestive of metastasis and should prompt search for a primary localization outside the retroperitoneum.     

Dedifferentiated myxoid liposarcoma: a clinicopathological study suggesting a closer relationship between myxoid and well-differentiated liposarcoma

Myxoid/round cell liposarcoma is arguably the commonest type of liposarcoma occurring in the extremities and may show gradual progression from low-grade, pure myxoid liposarcoma to high-grade round cell liposarcoma. Rarely myxoid/round cell liposarcoma is associated with areas of well-differentiated or pleomorphic liposarcoma (mixed liposarcoma). We describe the clinicopathological features of three unusual myxoid/round cell liposarcomas which showed morphological features of de novo dedifferentiation. All patients were male and were aged 66, 70 and 76 years, respectively. One lesion each arose in the retroperitoneum, inguinal region and peritoneal cavity. Histologically, in one case the myxoid/round cell component was juxtaposed to a high-grade non-lipogenic component resembling non-pleomorphic storiform 'malignant fibrous histiocytoma' ('MFH'), one case showed a combination of myxoid liposarcoma and a high-grade myxofibrosarcoma-like component (so-called myxoid 'MFH'), and in the third case, a well-differentiated myxoid liposarcoma with a discontinuous micronodular pattern of dedifferentiation was seen. Follow-up information of 30, 28 and 26 months revealed two recurrences each in two patients. These patients died of postoperative pulmonary embolism and abdominal haemorrhage, respectively; systemic metastases were not noted. These cases demonstrate that myxoid/round cell liposarcoma can show, albeit very rarely, histological features of dedifferentiation. Cases like these, combined with the occurrence of mixed-type liposarcoma (well-differentiated/myxoid liposarcoma) and the vicinity of chromosomal regions involved by specific karyotypic aberrations in these tumours, suggest that myxoid/round cell liposarcoma and well-differentiated liposarcoma (including its dedifferentiated variant) are more closely related in biological terms than is generally believed.     

脂肪组织源性肿瘤中c-myc和p53基因的异常表达

目的：探讨脂肪组织源性肿瘤与ｃ－ｍｙｃ和ｐ５３基因的关系。方法：采用ＬＳＡＢ免疫组化法,检测６２例脂肪组织源性肿瘤及瘤样病变ｃ－ｍｙｃ和ｐ５３蛋白表达。结果ｃ－ｍｙｃ在正常脂肪组织、脂肪组织良性病变中几乎不表达,主要在脂肪肉瘤中表达。ｐ５３只在脂肪肉瘤中表达。分化较高类型脂肪肉瘤ｃ－ｍｙｃ和ｐ５３表达阳性率明显低于分化较低类型脂肪肉瘤,脂肪肉瘤中,ｃ－ｍｙｃ和ｐ５３表达呈正相关。结论：实验结果提示     

Apropos of 1 case of paratesticular papillary serous cystadenocarcinoma

The occurrence within the testis or paratesticular tissue of serous tumors, similar to ovarian tumors, is rare. This article reports a primary serous paratesticular cystadenocarcinoma in a 39 year-old man. From data of the literature, we offer guidelines for diagnosis, histogenesis and treatment of this rare tumor.