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PubMed2006

Metastasis predictive signature profiles pre-exist in normal tissues.

Previous studies from our laboratory have demonstrated that metastatic propensity is significantly influenced by the genetic background upon which tumors arise. We have also established that human gene expression profiles predictive of metastasis are not only present in mouse tumors with both high and low metastatic capacity, but also correlate with genetic background. These results suggest that human metastasis-predictive gene expression signatures may be significantly driven by genetic background, rather than acquired somatic mutations. To test this hypothesis, gene expression profiling was performed on inbred mouse strains with significantly different metastatic efficiencies. Analysis of previously described human metastasis signature gene expression patterns in normal tissues permitted accurate categorization of high or low metastatic mouse genotypes. Furthermore, prospective identification of animals at high risk of metastasis was achieved by using mass spectrometry to characterize salivary peptide polymorphisms in a genetically heterogeneous population. These results strongly support the role of constitutional genetic variation in modulation of metastatic efficiency and suggest that predictive signature profiles could be developed from normal tissues in humans. The ability to identify those individuals at high risk of disseminated disease at the time of clinical manifestation of a primary cancer could have a significant impact on cancer management.

Animals↗

PubMed2006

Ovarian involvement by metastatic colorectal adenocarcinoma: still a diagnostic challenge.

Ovarian involvement by metastatic colorectal adenocarcinoma, although not an uncommon occurrence, remains a diagnostic challenge. The gross and histologic features of such metastases overlap those of primary ovarian epithelial neoplasms such as endometrioid or mucinous adenocarcinoma. The clinical and pathologic features of 86 cases of metastatic colorectal adenocarcinoma involving the ovary were reviewed. Patients ranged in age from 19 to 85 years (median, 51 years); 24% were younger than 40 years. Presenting symptoms included abdominal or pelvic pain (45 cases), rectal bleeding (13 cases), change in bowel habits (20 cases), and vaginal bleeding (5 cases). In 23 cases, an ovarian mass was the first manifestation of the disease. Ovarian involvement was bilateral in 49 cases and unilateral in 33 (including 20 cases in which the only involved ovary measured at least 10 cm in greatest dimension). Involved ovaries ranged from 2 to 24 cm (mean, 10.1 cm), and most featured both solid and cystic areas. Many involved ovaries featured smooth capsules without gross evidence of surface involvement by tumor. In general, the tumors had typical histologic features of metastatic colorectal adenocarcinoma, including a garland pattern and dirty necrosis. In 23 cases, foci with a benign or low malignant potential appearance were seen. Immunohistochemical studies showed that 29 of 29 tumors (100%) were positive for CK20; focal CK7 positivity was seen in 5 of 30 cases (17%). In 9 of the cases, an ovarian primary was diagnosed or favored initially, and 5 of these cases were initially treated as ovarian primaries. Metastatic colorectal adenocarcinoma should be considered in the differential diagnosis of an ovarian mass, even if the mass is large and unilateral or in a young patient, to secure proper treatment of these patients.

Adenocarcinoma↗

PubMed1987

Tissue polypeptide antigen (TPA) in pleural effusions.

The usefulness of tumor marker assay in pleural effusions for differential diagnosis is still debated. From the observation of common antigens on tissue polypeptide antigen (TPA) and keratins 8, 18 and 19 and vimentin, all substances contained in normal and neoplastic mesothelium, we felt it opportune to evaluate the use of TPA assay in 105 pleural effusions (46 benign and 59 malignant). The values were much higher than those found in blood. In hydrothorax the median value was 454 U/l (range, 59-1923), in exudative effusions 846 U/l (range, 258-4485), in metastatic pleural effusions 1277 U/l (range, 58-32352) and in mesotheliomas 7705 (range, 759-16000). The maximum value found in nonmalignant effusions was 4485 U/l; this value was taken as a cutoff level, so only 29.9% of the tumors were positive to the test. Our results showed this assay to be not very important for a differential diagnosis of malignant and nonmalignant pleural effusions. Nevertheless, the different TPA patterns in mesotheliomas (66.6% positive) and metastatic pleural effusions (15.9%) suggest that further studies are warranted.

Adult↗

PubMed1999

p53, p16 and RB expression in adenosquamous and squamous cell carcinomas of the stomach.

The expression of p53, p16 and RB proteins and their clinicopathologic correlation were investigated in 15 cases of primary gastric adenosquamous carcinoma and 2 cases of squamous cell carcinoma of the stomach. The male to female ratio of the patients was 13:4 and the average age was 55.7 years. None of the cases was early gastric carcinoma, and none of the adenocarcinoma components were of the diffuse or signet ring cell types. Fourteen cases showed metastasis to regional lymph nodes and/or other organs at the time of surgery. The adenocarcinoma component was metastasized to lymph nodes in 12 cases, and both adenocarcinoma and squamous cell carcinoma components were metastasized in three cases. The altered expression of p53 correlated with the advanced stage, but did not correlate with the depth of invasion, lymph node metastasis or recurrence. The altered expression of p16 and RB proteins did not correlate with any of the above clinico-pathologic factors. Both the adenocarcinoma and squamous cell carcinoma components revealed an inverse correlation between the expression pattern of p16 and RB proteins (p < 0.05). This suggests that the two proteins share a role in the carcinogenesis of these tumors. The expression pattern of p53 proteins in the adenocarcinoma and squamous cell carcinoma components was exactly the same in all of the cases. The expression patterns of p16 and RB protein were also identical in most of the cases. The expression patterns of all three proteins in the metastatic lesions were also identical to those in the primary lesions. The fact that the alteration of the three tumor suppressor gene products shares the same pattern suggests that squamous and adenocarcinoma components in the stomach originate from the same or a genetically related clone.

Adult↗

PubMed1987

Endometrioid-like variant of ovarian yolk sac tumor. A clinicopathological analysis of eight cases.

The clinical and pathological features of eight ovarian yolk sac tumors with glandular patterns resembling those of endometrioid adenocarcinoma are described. The patients ranged in age from 11 to 34 years (mean, 22 years) and presented with abdominal pain or swelling. The serum alpha-fetoprotein (AFP) level was elevated at the time of presentation or later in all seven patients in whom it was measured. Seven tumors were unilateral, one was bilateral, and three had spread beyond the ovary. There was a contralateral streak gonad in two cases. The tumors were 6-35 cm in diameter; seven were solid and cystic, and one was a unilocular cyst with a small solid nodule in the wall. Microscopic examination revealed a prominent, and in two cases, pure endometrioid-like glandular pattern that often simulated that of an early secretory endometrium. Reticular, polyvesicular-vitelline, and hepatoid patterns of yolk sac tumor were also present in five tumors; minor teratomatous foci (squamous epithelium and cartilage) were present in one. Immunohistochemical staining revealed AFP, alpha-1-anti-trypsin (AAT), and carcinoembryonic antigen within the glandular epithelium; AFP and AAT were also present in areas showing the other patterns. Three patients died of recurrent or metastatic tumor 19-60 months postoperatively; in the remaining cases, there was a tumor-free follow-up of short duration. The endometrioid-like pattern reflects an unusual form of endodermal differentiation within yolk sac tumors that should be distinguished from endometrioid carcinoma.

Adolescent↗

PubMed1988

Influence of host age on lung colony forming capacity of injected rat rhabdomyosarcoma cells.

Intravenous administration of RA-2 transplantable rhabdomyosarcoma cells produces development of metastatic tumour cell colonies in the lungs of host rats. After administration of 2 X 10(3), 5 X 10(3) or 10 X 10(3) RA-2 cells, different patterns of dependence of the number of metastatic clones in the lungs on injected cell number have been observed. The numbers of tumour cell colonies were shown to be highest in immature (1-month-old) and old (15-month-old) female rats compared to middle-age groups (3- and 12-month-old). A similar age-related pattern was observed in male rats. Analysis of the results obtained has revealed positive correlation between tumour cell colony numbers and both somatomedin activity and proliferation rate of neoplastic tissue.

Age Factors↗

PubMedDate not supplied

From the archives of the AFIP: benign fibrous tumors and tumorlike lesions of the mesentery: radiologic-pathologic correlation.

Mesenteric fibromatosis, sclerosing mesenteritis, inflammatory pseudotumor, and extrapleural solitary fibrous tumor constitute a loosely associated group of benign fibrous tumors and tumorlike lesions of the mesentery. These lesions are linked histologically by the presence of fibroblasts or fibrosis and anatomically by their location within the mesentery. Although rare, and distinctly different in pathogenesis and biologic behavior, these fibrous lesions have pathologic and radiologic features that overlap with one another and with more common neoplastic and nonneoplastic lesions of the mesentery. Mesenteric fibromatosis is a locally aggressive, benign proliferative process that may occur sporadically or in association with familial adenomatous polyposis. It most frequently manifests as a focal mesenteric mass and may simulate lymphoma, metastatic disease, or a soft-tissue sarcoma. Sclerosing mesenteritis is a rare idiopathic disorder that most commonly produces a stellate mass within the mesentery and should be differentiated from metastatic disease, specifically metastatic carcinoid, because it frequently responds to conservative or medical management. Inflammatory pseudotumor (inflammatory myofibroblastic tumor) is a benign, chronic inflammatory disorder of unknown cause that manifests as a solid mesenteric mass, indistinguishable from malignancy. Extrapleural solitary fibrous tumor is a tumor of submesothelial origin that is identical to the solitary fibrous tumor of the pleura. When located in the mesentery or peritoneal cavity, extrapleural solitary fibrous tumor has an imaging pattern that must be differentiated from metastatic disease, soft-tissue sarcomas, and other benign and malignant neoplasms of the mesentery and peritoneum. Knowledge of this group of benign fibrous tumors and tumorlike lesions of the mesentery is important in the preoperative evaluation of a mesenteric mass.

Adult↗

PubMed1985

Patterns of recurrence in patients with high-grade soft-tissue sarcomas.

From July 1975 to December 1982, 563 patients were referred to the Surgery Branch of the National Cancer Institute with the diagnosis of soft-tissue sarcoma. Three hundred and seven of these patients had fully resectable, localized high-grade soft-tissue sarcomas and were treated at the National Cancer Institute using standard protocols with surgery alone, or in combination with chemotherapy and/or radiotherapy. An aggressive surgical approach was undertaken in the management of patients who subsequently developed recurrent disease. These 307 cases have been reviewed, with a median duration of follow-up of 30 months, to determine the frequency of recurrent disease, the patterns of recurrence, and the impact of surgery on the survival of patients who developed recurrent disease. Disease recurred in one hundred seven patients (107/307, 35%), with a median disease-free interval of 18 months (range, 0.5 to 72.0 months). The frequency of recurrence by site of primary sarcoma was extremity, 31% (65/211); head and neck, 33% (4/12); trunk, 40% (17/42); retroperitoneum, 47% (17/36); and breast, 67% (4/6). Isolated pulmonary metastatic disease was the most common pattern of initial recurrence (56/107, 52%) followed by isolated local recurrence (21/107, 20%). Single other sites of recurrence and multiple concurrent sites of recurrence each accounted for 14% (15/107) of all initial recurrences. The relative frequency of each of these four patterns of recurrence varied with the site of the primary sarcoma. The outcome for patients with recurrent disease depended on the site of recurrence, rather than on the site of the primary sarcoma. Sixty-six patients (66/107, 62%) with recurrent disease were rendered surgically disease-free with the first recurrence, including 40 (40/56, 72%) patients with isolated pulmonary metastases, 20 patients (20/21, 96%) with isolated local recurrences, five patients (5/15, 33%), with isolated other sites of recurrence and one patient (1/15, 7%) with multiple sites of initial recurrence. Following surgical resection, the actuarial three-year survival for the 66 patients rendered disease-free was 51%. The median survival for the 41 patients not rendered surgically disease-free with the first recurrence was only 7.4 months. Thirty of the sixty-six patients (30/66, 45%) rendered disease-free with the first recurrence remained disease-free at follow-up, with a median follow-up of 28 months from the time of resection of the first recurrence. The remaining 36 patients (36/66, 55%) subsequently recurred, with a median disease-free interval of 7.3 months.(ABSTRACT TRUNCATED AT 400 WORDS)

Adolescent↗

PubMed2005

Altered expression and deletion of RMO1 in osteosarcoma.

In order to increase our understanding of the molecular events underlying osteosarcoma progression, the expression of approximately 950 genes was examined in 24 primary and metastatic osteosarcoma tumor specimens. A gene, RMO1, was isolated with decreased expression in metastatic samples. Real-Time PCR corroborated this pattern, revealing lower expression in the primary sample in 6 of 7 cases for which both primary and metastatic osteosarcoma samples were available from the same patient (p = 0.034). RMO1 is located at 2q33, a region of frequent loss of heterozygosity in cancer, and exhibited loss of heterozygosity in 6 out of 9 primary osteosarcoma tumor samples (67%). Loss of heterozygosity is evident in primary tumors while the decrease in gene expression is seen in the metastatic samples, indicating that these 2 events are separately implicated in cancer progression. Cloning of RMO1 revealed an open reading frame with multiple splice forms with significant homology to GRB7, 10 and 14 and MIG10 in the region containing a Pleckstrin homology domain and a Ras association domain, suggestive of a role in cell signaling and migration. Northern blot analysis indicated that RMO1 mRNA is ubiquitously expressed in tissues except for peripheral blood leukocytes. These data suggest that RMO1 may be a candidate for a protein involved in inhibiting tumor progression.

Alternative Splicing↗

PubMed1981

In vitro chemotherapeutic testing of urologic tumors.

We studied 20 transitional cell tumors of the bladder and 25 adenocarcinomas of the kidney in vitro to determine their chemotherapeutic sensitivity. The different sensitivity patterns among the individual tumors were demonstrated. Identical drug sensitivity patterns could be identified in the primary and metastatic sites, and in tumor tissue removed from the primary and metastatic deposits in the same patient. Human renal adenocarcinoma maintained in the athymic mouse demonstrated identical chemotherapeutic sensitivity patterns in vitro and in vivo. Our data would support that these in vitro chemotherapy studies may assist in the selection of agents to use in human tumor-bearing hosts.

Adenocarcinoma↗

PubMed1987

Glycosphingolipids of lectin-resistant mutants of the highly metastatic mouse tumor cell line, MDAY-D2.

Neutral and acidic glycolipids in MDAY-D2, a highly metastatic murine tumor cell line, were examined and compared with glycolipids of MDW4 and D33W25-1, two lectin-resistant mutants of MDAY-D2 from distinct genetic complementation classes. D33W25-1 remained highly metastatic while MDW4 cells were found to be nonmetastatic (Dennis, J. W., Donaghue, T., Florian, M., and Kerbel, R. S., Nature (Lond.), 292: 242-245, 1981 and Dennis, J. W. et al., Cancer Res., 46: 4594-4600, 1986). Glycolipid structures were identified by fast-atom bombardment mass spectrometry, methylation analysis, exoglycosidase treatment, and immunostaining. The metastatic MDAY-D2 was found to contain GM3, GM2, IV3GalNAc-GM1b, and high levels of GM1a, GM1b, and GD1a. MDW4 showed a 3-fold decrease in total ganglioside content compared to MDAY-D2 and a corresponding increase in the precursor, glucosylceramide. MDW4 was deficient in GM1 and accumulated GM2 and NeuNG-GM2, indicating a lack of gangliosides having NeuNAc alpha 2-3Gal beta 1-3 terminal sequence. Neosynthesis of GD3 was also observed in MDW4. The metastatic mutant D33W25-1 had a similar pattern of gangliosides as that found in MDAY-D2 cells with N-glycolyl rather than N-acetyl neuraminic acid. These results suggest that the metastatic property of these cell lines may be related to the level of ganglioside, and that the substitution of N-glycolyl for N-acetyl neuraminic acid does not reduce metastatic capacity.

Animals↗

PubMed1996

Lack of adhesion molecules in testicular diffuse centroblastic and immunoblastic B cell lymphomas as a contributory factor in malignant behaviour.

Diffuse large B-cell lymphoma of the testis is a rare tumour, often with disseminated disease. According to the Kiel Classification, these lymphomas are of centroblastic or immunoblastic type, corresponding in the Working Formulation to malignant lymphoma, large cell non-cleaved and large cell immunoblastic, respectively. Adhesive cell-cell and cell-matrix interactions are generally assumed to play an important part in the metastatic process, and to find clues to the highly malignant biological behaviour of this tumour we examined expression of integrins and other adhesion molecules on the tumour cells and the presence of matrix proteins. Few adhesion molecules appeared to be expressed. CD44 was expressed in 10/12 lymphomas, CD49f/VLA-6 was positive in 5/12 cases, and CD49d/VLA-4, CD54 and CD62L were detectable in a small number (2-3) of lymphomas. All other adhesion molecules were lacking. This expression pattern is suggestive of a high metastatic potential: the tumour cells seem to be poorly attached to the extracellular matrix, to each other and to other cells (CD54-, CD11a-, CD58-). The adhesion molecules expressed, CD44, CD49f/VLA-6 and CD49d/VLA-4, have been reported to play a part in dissemination, mediating intravasation (CD49f/VLA-6) and extravasation (CD44, CD49d/VLA-4). This profile of adhesion molecules may explain, at least in part, the specific biological behaviour of these lymphomas with early and rapid dissemination.

Cell Adhesion Molecules↗

PubMed2000

Immunohistochemical localization of ornithine decarboxylase in skin tumors.

BACKGROUND: Ornithine decarboxylase (ODC) plays an important role in the biosynthesis of polyamines. Induction of ODC and polyamine synthesis has been demonstrated in neoplastic tumors and is thought to be related to the degree of malignancy. METHODS: In this study, we investigated a series of basal cell epitheliomas (BCE), Bowen's disease, squamous cell carcinomas (SCC), and metastatic tumors of the skin using an antibody against ODC for immunohistochemistry. RESULTS: Eight of 12 cases of BCE failed to show a positive reaction for ODC. In Bowen's disease, 5 of 13 cases diffusely showed positive reaction for ODC. Fourteen of 15 cases of SCC showed ODC expression, the intensity of which was decreased in the peripheral layer. At higher magnification, the distribution of ODC in the positive SCC cases showed granular and heterogenous patterns. Ten of 14 cases of metastatic skin tumors exhibited positive reactions, and well-differentiated adenocarcinomas tended to show more strongly positive than poorly-differentiated ones. CONCLUSIONS: These results support the conclusion that the intensity and the incidence of positive immunohistochemical staining for ODC correlate with the degree of cellular differentiation, and furthermore, that heterogenous distribution of ODC staining may be associated with heterogeneity of tumor cells.

Bowen's Disease↗

PubMedDate not supplied

[Correlation of steroid receptors and growth factors expression with peritumoral edema accompanying cerebral neoplasms].

The aetiology of peritumoral brain oedema still remains unclear, despite investigations, attempted to study the role of various clinical factors and histological features of the tumour. The aim of this investigation was to the evaluate correlation of peritumoral brain oedema with expression of progesterone (PR) and oestrogen (ER) receptors and vascular--endothelial growth factor (VEGF). Eighty nine samples of brain tumours were examined, among them 28 meningiomas, 43 gliomas and 18 metastatic tumours. Expression of steroid receptors was examined with the radioreceptor assay method and expression of VEGF by radioimmune assay. A statistically highly significant correlation was found of VEGF expression with the incidence of diffuse pattern of brain oedema around gliomas and metastatic tumours (p < 0.01). PR expression was associated significantly with the occurrence of localized type of oedema around meningiomas, but in gliomas the expression of this receptor correlated with a diffuse pattern of oedema. No correlation was found between ER expression and peritumoral brain oedema.

Brain Edema↗

PubMed2004

Dynamic computed tomography and color Doppler ultrasound of renal parenchymal neoplasms: correlations with histopathological findings.

BACKGROUND: We evaluated whether color Doppler ultrasound (US) had diagnostic accuracy equal to dynamic computed tomography (CT) and whether performing dynamic CT and Doppler US together would be more informative in preoperative diagnosis of renal solid tumors. METHODS: A total of 110 renal solid tumors smaller than 7 cm were evaluated with dynamic CT and Doppler US. We compared the enhancement and the color flow patterns with the histopathological subtypes. RESULTS: Eighty-seven (95.6%) of 91 clear cell carcinomas showed rich enhancement in the cortical nephrographic phase (CNP) and 82 (90.1%) of them had color flow in the Doppler US. Of the total of 110 tumors, nine (8.1%) did not show color flow in spite of rich enhancement in the CNP. Conversely, eight (7.2%) of the 110 tumors showed color flow in spite of poor enhancement, including two chromophobe cell carcinomas and two metastatic renal tumors. CONCLUSIONS: The enhancement pattern in dynamic CT and the color flow pattern in Doppler US were different among the subtypes of RCC. Color Doppler US had diagnostic accuracy equal to dynamic CT in most patients with renal solid tumors. Although Doppler US may play a unique role in the diagnosis of some renal parenchymal solid tumors, it is sufficient to perform dynamic CT alone for diagnosis of clear cell carcinoma.

Adenocarcinoma, Clear Cell↗

PubMed1990

The role of platelets in cancer metastasis.

Clinical, experimental and ultrastructural studies strongly suggest a role for platelets in metastatic dissemination. Several mechanisms have been proposed to explain the potential contribution of blood platelets to the metastatic cascade. Experimentally, many tumour cells of either animal or human origin have the capacity to activate platelets, although the mechanisms by which malignant cells exert this effect is not yet fully understood. Possible mechanisms include: (1) generation of thrombin; (2) activation by ADP; (3) release of cathepsin B; (4) eicosanoid metabolism. A number of observations also indicated that tumour-cell-induced platelet aggregation required specific receptor sites. We have shown that platelet glycoprotein GPIb and the complex GPIIb/IIIa are necessary for tumour-cell-induced platelet aggregation. We and others reported the isolation of a microparticulate aggregating material from different types of tumour cell lines. This material has been identified as a sialolipoprotein complex which possesses tissue-factor-like activity. The role of sialic acid in the metastatic potential of cells is also believed to be important and may partly modulate their interactions with platelets. In vivo, rheological factors may also regulate the interactions of tumour cells with blood and vascular structures and an alternative approach to the evaluation of platelet-tumour-cell interaction under dynamic conditions has been the use of perfusion systems. Thus, we have established the crucial role of Ca2+ in supporting tumour-cell-platelet activation and subsequent thrombus formation. More recently we investigated the patterns of adhesion of a highly metastatic human adenocarcinoma of the lung to exposed extracellular matrix generated by human vascular endothelial cells in culture.(ABSTRACT TRUNCATED AT 250 WORDS)

Adenosine Diphosphate↗

PubMed2002

Metastatic squamous cell carcinoma of the neck from an unknown primary: management options and patterns of relapse.

PURPOSE: Management of squamous cell carcinoma of undetermined primary tumors in the head and neck region is controversial. Here we report the Southern California Kaiser Permanente experience with these patients. METHODS AND MATERIALS: From January 1969 through December 1994, 106 patients were eligible for this retrospective analysis. Distribution of nodal staging was as follows: 14 N1, 27 N2A, 39 N2B, 2 N2C, and 24 N3. Initial treatment included excisional biopsy alone in 12, radical neck dissection alone in 29, radiotherapy alone in 24, excisional biopsy followed by radiotherapy in 15, and radical neck dissection plus postoperative radiation in 26 patients. RESULTS: Except for two patients, all patients have had a minimum follow-up of 5 years. Overall, 57 patients (54%) have had recurrences. Only two patients (3%) who had received radiotherapy as part of their initial treatment had an appearance of a potential primary site inside the irradiated field vs 13 patients (32%) who had not received radiotherapy (p =.006). Combined modality therapy resulted in fewer neck relapses, particularly in patients with advanced neck disease. Including salvage, surgery alone as the initial treatment resulted in 81% ultimate tumor control above the clavicle for patients with N1 and N2a disease without extracapsular extension. The 5-year survival for the entire population was 53%. Radiotherapy alone resulted in poor survival in patients with advanced/unresectable neck disease. No significant difference in survival based on the initial treatment was found. The statistically significant adverse factors in determining survival included advanced nodal stage and the presence of extracapsular extension. CONCLUSIONS: Radiotherapy is very effective in reducing the rate of appearance of a potential primary site. However, in the absence of advanced neck disease (N1 and N2A without extracapsular extension), radiotherapy can be reserved for salvage. Radiotherapy alone results in poor outcomes in patients with advanced/unresectable neck disease, and incorporation of concurrent chemotherapy and cytoprotective agents should be investigated.

Carcinoma, Squamous Cell↗

PubMed2005

Distant metastasis in retroperitoneal dedifferentiated liposarcoma is rare and rapidly fatal: a clinicopathological study with emphasis on the low-grade myxofibrosarcoma-like pattern as an early sign of dedifferentiation.

The metastatic incidence of retroperitoneal dedifferentiated liposarcoma is comparatively lower than other pleomorphic sarcomas, varying widely from 1 to 18%. Low-grade dedifferentiation resembling low-grade fibrosarcoma has been recently accepted as part of the morphologic spectrum of dedifferentiated liposarcoma and was reported to have similar metastatic and survival rates to its high-grade counterpart. We sought to determine the metastatic incidence of retroperitoneal dedifferentiated liposarcoma, the clinicopathological features related to metastasis, and their postmetastatic behavior. Of all 354 retroperitoneal liposarcoma cases diagnosed at Memorial Sloan-Kettering Cancer Center during 1982-2003, we identified seven patients developing distant metastases, occurring in four females and three males, ranging from 35 to 73 years in age at presentation. They were all de novo dedifferentiated, while none of the well-differentiated liposarcoma or secondary dedifferentiated liposarcoma developed distant metastasis. Primary tumor sizes varied from 7.5 to 25 cm. All seven patients developing metastases contained >or=50% dedifferentiated elements in the primary tumor, with a predominant morphology resembling myxofibrosarcoma in five cases. The metastatic sites included the lung in four patients, somatic soft tissue in two, and liver in one. The median metastasis-free survival was 48 months, with only two patients experiencing local recurrences before developing metastasis. Six patients died of disease at median follow-up of 53 months after diagnosis and only 5 months after their first metastases. In conclusion, retroperitoneal dedifferentiated liposarcoma have a low metastatic rate, which is strongly related to de novo dedifferentiated histology that usually constitutes a prominent component of the primary tumor. Irrespective of the grade dedifferentiated liposarcoma with myxofibrosarcoma-like features should be closely monitored. Once metastases occur, they tend to follow a rapidly fatal course.

Adult↗