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PubMed1997

Malignant mucosal melanoma of the head and neck: review of the literature and report of 14 patients.

BACKGROUND: Fortunately, primary malignant mucosal melanoma of the head and neck is a rare entity. A paucity of data elucidating the predictive factors as well as the unpredictable and aggressive biologic behavior of mucosal melanoma compound the vexing clinical situation. This review summarizes what the literature reveals about the epidemiology, patient survival, patterns of local recurrence, and local and distant metastasis of the disease. Over 1000 patients with this disease have been reported. Survivals at 5 and 10 years is 17% and 5%, respectively. Approximately 19% of patients present with lymph node metastasis and another 16% develop lymph node metastases after treatment, whereas 10% present with distant metastasis. Local metastasis does not affect survival; this is in sharp contrast with skin melanoma. Over 50% of patients experience local treatment failure, and salvage treatment is effective in only 25% of these cases. Local failure is the harbinger of distant metastases. Patients with nasal mucosal melanoma have a 31% 5-year survival rate, whereas sinus melanoma patients fare poorly, with a 0% rate of 5-year survival. METHODS: The authors conducted a retrospective review of 14 patients with characteristics similar to those in the literature in terms of outcome. RESULTS: The 5-year survival rate for these patients was 14%. Whole-body positron emission tomography was performed on 3 patients to detect metastatic disease. The patterns of local recurrence, distant metastasis, and survival for these patients were compared with the same data for patients described in the literature. CONCLUSIONS: Surgery appears to have the greatest efficacy in the management of mucosal melanoma, although radiation therapy may play an increasingly important role in the future.

Aged↗

PubMed2000

Pulmonary metastasis with an endobronchial growth pattern: report of a case.

We herein report a case of a pulmonary metastatic tumor with an endobronchial growth pattern. A 75-year-old female was operated on for pulmonary metastasis which originated from a malignant melanoma of the upper gum. Computed tomography (CT) of the chest demonstrated a solitary mass in right S6 region and a preoperative bronchoscopic examination revealed an endobronchial tumor in rtB6b. A retrospective analysis of the chest CT showed a thickened bronchial wall extending to the entrance of rtB6b. Therefore, not a wedge resection but a segmentectomy (rtS6) was performed. When the surgical margin is determined, we should therefore keep in mind the possibility of an endobronchial growth pattern if only a solitary mass is recognized on the CT, even though pulmonary metastatic tumors showing an endobronchial growth pattern is uncommon.

Aged↗

PubMed2002

Case report. Metastatic pulmonary calcification in renal failure: a new HRCT pattern.

A 56-year-old male with chronic renal failure presented with a 6 month history of progressive dyspnoea. High resolution CT of the chest showed multiple, peripheral, centrilobular nodules in the upper and mid zones, consistent with metastatic pulmonary calcification. Some of these pulmonary nodules showed ring calcification, a pattern that to our knowledge has not been described before. Calcification was also seen in the segmental pulmonary arteries, bronchi, trachea and subcutaneous vessels of the chest wall.

Calcinosis↗

PubMed2001

Metastatic metaplastic carcinoma of the breast (MCB): an uncharacteristic pattern of presentation with clinicopathologic correlation.

Metaplastic carcinoma of the breast (MCB) is a well recognized but uncommon aberrant manifestation of poorly differentiated invasive carcinoma containing both epithelial (ductal) and mesenchymal elements as well as a transitional form between them. This heterogeneous tumor characteristically contains ductal carcinoma cells mixed with areas of diverse morphologic phenotype displaying spindle, squamous, chondroid, or osseous differentiation. Some studies have suggested that certain types of metaplastic carcinoma have a more favorable prognosis as compared with others. We describe a case involving a 67-yr-old woman who presented with metastatic nodules in the lungs and a vague but recent history of breast cancer. The case highlights a subtype of MCB with a predominant spindle cell component metastatic to the lung. Fine-needle aspiration biopsy (FNAB) smears of the nodules revealed a bland, spindle cell, mesenchymal proliferation with minimal evidence of an epithelial component. A second primary was clinically excluded and a request for review of the original slides identified a metaplastic component to the original tumor with a histologic and immunohistochemical profile identical to the metastatic tumor, confirming origin from the breast. Metaplastic carcinomas of the breast commonly bypass axillary lymph nodes and present as distant metastases. FNAB diagnosis of metaplastic carcinoma of the breast is quite difficult at the primary site and poses a formidable diagnostic challenge at a metastatic site, especially when the dominant pattern is not of the usual type. The literature is reviewed, confirming the rarity of such a presentation and the novelty of this case. Confirmation by FNAB is also quite difficult but may become more commonplace as a trend toward minimal intervention continues to gain popularity. This case emphasizes the importance of recognizing and reporting metaplastic elements in primary breast tumors, as well as the value of direct morphologic comparison of cytologic material from FNABs with archival histologic material. In such situations, the importance of complete and accurate clinicopathologic information is underscored.

Aged↗

PubMed1985

The changing management of Wilms' tumor over a 30-year period. 1949-1978.

Seventy-four patients with histologically confirmed diagnoses of Wilms' tumor were treated between 1949 and 1978 at the Mallinckrodt Institute of Radiology and St. Louis Children's Hospital. The results have been divided into two eras of therapy, i.e., before and after 1965, when chemotherapy became a major modality for Wilms' tumor therapy. Analysis at 5 years by era of therapy has shown similar disease-free survival results for Stage I ("prechemotherapy" era 67% versus "chemotherapy" era 75%), whereas the Stage II ("prechemotherapy" era 33% versus "chemotherapy" era 100%) and Stage III ("prechemotherapy" era 0% versus "chemotherapy" era 70%) are significantly different (P less than 0.001). This suggests that chemotherapy has substituted for postoperative irradiation in Stage I patients; whereas in Stage II and III, improved survival occurs as a result of the eradication of subclinical metastatic disease. The patterns of failure by era of treatment are presented and the literature is discussed.

Adolescent↗

PubMed1989

Gastric cancer heterogeneity.

This study was carried out on 222 samples from 37 gastric carcinomas to assess the incidence of multiple stem lines in primary tumors and metastasis as reflected by multiple DNA stem lines and their relationship to epidermal growth factor (EGF) receptor expression, histologic grade, tumor size, and degree of wall infiltration. Fifteen primary tumors (40.5%) were homogeneously diploid/peridiploid whereas 22 (59.5%) were aneuploid. In the lymph node metastasis, seven patients (29.2%) had an homogeneous diploid/peridiploid pattern in all metastatic lymph nodes. On the other hand, 17 (70.8%) had at least one aneuploid peak in the lymph node metastasis. DNA content heterogeneity was seen in 12 (33%) of primary tumors whereas 14 (66.6%) of 21 patients had multiple cell clones in the metastasis. Therefore, 12 patients had a metastatic clone which was not observed in the primary tumor. DNA content heterogeneity was seen even in tumors with submucosal invasion suggesting that this phenomenon is also present at earlier stages. No correlation between the histologic grade and the DNA distribution was observed. Furthermore, histologic heterogeneity was independent of DNA content heterogeneity. The EGF receptor expression was observed in six of the 23 patients in whom this analysis was done. The EGF receptor expression was constant in all samples which were studied and even samples with a different DNA content and histologic grade were stables for the EGF receptor expression.

Carcinoma↗

PubMed2006

Follicular variant of papillary thyroid carcinoma: a clinicopathologic study of a problematic entity.

BACKGROUND: There is continuous debate regarding the optimal classification, prognosis, and treatment of the follicular variant of papillary thyroid carcinoma (FVPTC). The objective of this study was to assess the behavior of FVPTC, especially its encapsulated form, and shed more light on its true position in the classification scheme of well differentiated thyroid carcinoma. METHODS: All patients with FVPTC, follicular thyroid adenoma (FTA), and follicular thyroid carcinoma (FTC) who were diagnosed between 1980 and 1995 were reviewed and reclassified according to the currently accepted definition of FVPTC. The tumors were separated into encapsulated and nonencapsulated (infiltrative/diffuse) types. Encapsulated tumors were subdivided further into tumors with or without capsular/vascular invasion. These different subtypes of FVPTC were correlated with outcome and with other clinicopathologic parameters. RESULTS: After review by 4 pathologists, 78 patients were included in the study. Sixty-one of 78 patients (78%) had encapsulated tumors (18 invasive, 43 noninvasive), and 17 patients had nonencapsulated tumors (infiltrative/diffuse). The gender distribution, age at presentation, and tumor size did not differ between patients with encapsulated and nonencapsulated FVPTC. Patients who had encapsulated FVPTC had a significantly lower rate of marked intratumor fibrosis (18%), extrathyroid extension (5%), and positive margins (2%) compared with patients who had nonencapsulated tumors (88%, 65%, and 50% respectively; P < .0001). Regional lymph node metastases were present in 14 of 78 patients (18%), and no patients had distant metastases. The lymph node metastatic rate was significantly higher in patients who had nonencapsulated tumors (11 of 17 patients; 65%) compared with patients who had encapsulated neoplasms (3 of 61 patients; 5%; P < .0001). In addition, lymph node metastases were not detected in any noninvasive, encapsulated FVPTCs. With a median follow-up of 10.8 years, only 1 patient developed a recurrence, which occurred in an encapsulated FVPTC that had numerous invasive foci. None of the patients with noninvasive, encapsulated FVPTCs developed recurrences, including 31 patients who underwent lobectomy alone, with a median follow-up of 11.1 years. CONCLUSIONS: FVPTC appeared to be a heterogeneous disease composed of 2 distinct groups: an infiltrative/diffuse (nonencapsulated) subvariant, which resembles classic papillary carcinoma in its metastatic lymph node pattern and invasive growth, and an encapsulated form, which behaves more like FTA/FTC. Patients who had noninvasive, encapsulated FVPTCs did not develop lymph node metastases or recurrences and could be treated by lobectomy alone. If the current findings are confirmed, then strong consideration should be given to reclassifying encapsulated FVPTC as an entity that is close to the FTA/FTC class of tumors.

Adenocarcinoma, Follicular↗

PubMedDate not supplied

Role of modern imaging in decision-making for elective neck dissection.

This study examines patterns of early metastatic spread as recorded in 19 clinically negative, histologically positive (occult) neck dissection specimens. Microscopic metastatic deposits were detected in this study in nodes measuring 10 mm and less. No nodes with extension of tumor beyond the capsule and into adjacent structures were noted. Central necrosis was detected in only one node. We suggest that the first stages of metastatic disease as evaluated by the pathologist in clinically occult nodes are minimal and may easily evade the eyes of both pathologists and radiologists. Imaging proved to be efficacious in upstaging clinically occult necks that were previously irradiated.

Head and Neck Neoplasms↗

PubMed1984

Nonmetastatic tumor cells acquire metastatic properties following somatic hybridization with normal cells.

Somatic cell hybridization between nonmetastatic tumor cells and normal cells of the lymphoreticular system results in hybrid cells manifesting metastatic properties of defined target organ specificity. Thus, fusion of the nonmetastatic BALB/c originated NSI plasmacytoma with C57BL B lymphocytes resulted in hybridomas, each of which were metastatic. Of 10 hybridomas, 7 generated metastases in the spleen and liver, whereas 3 generated liver metastases. The generation of liver metastases by hybridomas which homed to both spleen and liver, but not by those which homed to the liver only, was controlled by the spleen. The acquisition of metastatic properties via somatic cell fusion seems to represent a general principle, in which the normal partner determines the target organ specificity for the metastatic growth. Thus, fusion of SP2/O myeloma cells with syngeneic B lymphocytes also resulted in a hybrid cell metastasizing to the spleen and liver, yet a somatic hybrid between NSI and a macrophage or dendritic-like cell metastasized to the lung. Cell surface molecules encoded by the genome of the normal partner was demonstrated to control the target organ specificity: antibodies against MHC-encoded antigens of the normal B cell partner prevented the generation of metastases by hybridomas metastasizing to the spleen and liver, but not by those metastasizing to the liver only. This is in accordance with the function of MHC molecules on lymphocytes in controlling their homing to lymphoid organs. Hybridomas of T cell lymphomas also manifested metastatic properties. Analysis of the cell surface Thy-1 antigens of a hybridoma (DCH10), produced via somatic fusion between BW5145 lymphoma and a putative macrophage cell indicated that cells of liver metastases (DCH10-Li) generated by the hybrid cells might have undergone further somatic cell fusion in vivo with host (T?) cells. These cells have acquired new metastatic properties, generating metastases in spleen, liver and kidneys. In fact, even the inoculation of the parental BW lymphoma cells resulted in a case of liver metastasis (BW-Li). Such BW-Li cells, upon reinoculation, also generated metastases in the spleen, liver and kidneys. Analysis of the Thyl phenotype indicated that BW-Li cells may also have undergone somatic cell fusion in vivo with host (T?) cells, resulting in the acquisition of metastatic properties. The pattern of cell-cell interactions (adhesion, infiltration) with liver cell monolayers of BW-Li cells and of DCH10-Li (T-cell lymphomas) was identical, and differed from cells of liver metastases of the myeloma-B cell hybridomas which might be based on responses to liver growth signals.(ABSTRACT TRUNCATED AT 400 WORDS)

Animals↗

PubMed2005

Proteomic analysis on metastasis-associated proteins of human hepatocellular carcinoma tissues.

PURPOSE: A comparative proteomic approach was used to identify and analyze proteins related to metastasis of hepatocellular carcinoma (HCC). METHODS: Proteins extracted from 12 HCC tissue specimens (six with metastases and six without) were separated by two-dimensional gel electrophoresis (2-DE). The protein spots exhibiting statistical alternations between the two groups through computerized image analysis were then identified by mass spectrometry. In addition immunohistochemistry (IHC), Western blotting and RT-PCR were performed to verify the expression of certain candidate proteins. RESULTS: 16 proteins including HSP27, S100A11, CK18 were annotated by mass spectrometry, relevant to chaperone function, cell mobility, cytoskeletal architecture, respectively. Most were previously unconnected with metastasis of HCC. Of these HSP27 was found overexpressed consistently in 2-DE patterns of all metastatic HCC tissues compared with nonmetastatic ones. IHC and Western blotting of HCC tissues confirmed this difference while RT-PCR did not. CONCLUSION: There are various proteins joined together in HCC metastasis. The overexpression of HSP27 may serve as a biomarker for early detection and therapeutic targets unique to the metastatic phenotype of HCC.

Actins↗

PubMed2001

Pattern of lymph node micrometastasis and prognosis of patients with colorectal cancer.

BACKGROUND: Studies of lymph node micrometastases in patients with colorectal cancer have ignored the prognostic significance of the number and level of lymph node micrometastases. The aim of this study was to clarify the prognostic significance of the status of lymph node micrometastases in histologically node-negative colorectal cancer. METHODS: We used immunohistochemistry with anti-cytokeratin antibody CAM5.2 to examine 1013 lymph nodes in 42 patients (12 recurrent and 30 nonrecurrent) with histologically determined Dukes' B colorectal cancer. Five serial 6-microm sections were used for immunohistochemical staining. The frequency, tumor cell pattern, and number and level of lymph node micrometastases were compared between the recurrent and nonrecurrent groups. RESULTS: Micrometastasis was confirmed in 16% (59/373) of lymph nodes in the recurrent group and 12% (77/640) of lymph nodes in the nonrecurrent group, and the frequency of lymph node micrometastases was 92% (11/12) in the recurrent group and 70% (21/30) in the nonrecurrent group. The tumor cell pattern in the metastatic lymph nodes was similar in the recurrent and nonrecurrent groups. Micrometastasis in four or more lymph nodes occurred more frequently in the recurrent group than in the nonrecurrent group (58% vs. 20%, P < .05), and micrometastasis to N2 or higher nodes occurred more frequently in the recurrent group than in the nonrecurrent group (92% vs. 47%, P < .01). CONCLUSIONS: The number and level of positive micrometastatic lymph nodes was significantly correlated with postoperative recurrence of histologically determined Dukes' B colorectal cancer. This parameter is a useful prognostic indicator in histologically node-negative colorectal cancer and is helpful in planning adjuvant chemotherapy.

Aged↗

PubMed1985

Development of nongerm cell malignancies in nonseminomatous germ cell tumors.

We report 2 cases of sarcomatous transformation of mixed germ cell tumors of the testis. Both patients received cisplatin-based combination chemotherapy. Embryonal rhabdomyosarcoma, chondrosarcoma and spindle cell sarcoma were the dominant pathological patterns in the metastatic sites. Nongerm cell malignancies in mixed germ cell tumors following chemotherapy may be more common than previously described.

Adult↗

PubMed1999

Progression-related expression of beta3 integrin in melanomas and nevi.

The expression of the beta3 integrin subunit was investigated in 130 fixed, paraffin-embedded specimens of human melanomas and nevi using two different monoclonal antibodies. Expression was not observed in melanocytes and was absent or low in most nevi. In primary melanomas, expression was absent or low in the nontumorigenic radial growth phase, which includes the classes of in situ and microinvasive melanomas. In contrast, expression was high in the tumorigenic or vertical growth phase compartment of many primary melanomas and in most metastatic melanomas. Expression patterns were similar with the two antibodies, SSA6 and SAP, and was membrane-related as well as cytoplasmically expressed. In those nevi that reacted focally, the reactivity tended to occur in the dermal component of neurotized nevi, and in Spitz nevi, where the reactivity was stronger and more diffuse. A few dysplastic nevi showed focal reactivity of the junctional component. These results are consistent with tumor progression-related expression of the beta3 integrin, which is expressed in melanocytic tumors as the alphavbeta3 integrin, having affinity for matrix molecules, including vitronectin and fibronectin. In all melanomas, and in the subset of tumorigenic vertical growth phase melanomas, expression increased with thickness (P < .01). For this reason, and because ligation of this integrin has been shown in vitro to have several properties that may be related to the malignant phenotype, it is likely that expression of this marker may have prognostic value. However, because of its consistent and strong expression in Spitz nevi, the diagnostic utility of this marker will likely be limited.

Aged↗

PubMed2002

Complex microcirculation patterns detected by confocal indocyanine green angiography predict time to growth of small choroidal melanocytic tumors: MuSIC Report II.

PURPOSE: Multiple independent laboratories have confirmed the histologic observation that some tumor microcirculation patterns (MCPs) in uveal melanomas are associated strongly with death resulting from metastatic disease. Because these patterns are imageable with confocal indocyanine green angiography (ICG), we designed a prospective study to evaluate whether these angiographically detectable MCPs predict time to tumor growth. DESIGN: Observational case series, prospective, non-randomized. PARTICIPANTS: Ninety-eight patients with unilateral, small, choroidal melanocytic tumors. METHODS: The following information and tumor characteristics were recorded for each patient: demographic parameters, best-corrected visual acuity, intraocular pressure, related visual symptoms, location and dimension of tumor, pigmentation, orange pigment, drusen, tumor-associated hemorrhage, subretinal fluid, and confocal ICG angiographically determined microcirculation patterns-silent (avascularity), normal (preexisting normal choroidal vessels within the tumor), straight vessels, parallel without and with cross-linking, arcs without and with branching, loops, and networks. MAIN OUTCOME MEASURES: Time to growth of the tumor, with growth defined as an increase in the maximal apical tumor height of 0.5 mm measured by standardized A-scan ultrasonography, photographic documentation of an increase of the largest basal diameter of at least 1.5 mm, advancement of one tumor border of at least 0.75 mm, or a combination thereof. RESULTS: Twenty-eight of the 98 tumors in this study (29%) met the predetermined criteria for tumor growth. The median time to growth was 127 days (range, 51-625 days). The following tumor characteristics were significantly associated with time to tumor growth: flashes (P = 0.0224), orange pigment (P = 0.012), subretinal fluid (P < 0.001), maximum basal tumor diameter at initial examination (P = 0.015), maximum apical tumor height (P < 0.001), parallel with cross-linking MCP (P < 0.001), arcs with branching MCP (P = 0.006), loops (P < 0.001), and networks (P < 0.001). Of these, the angiographic documentation of any of the complex MCPs (parallel with cross-linking, arcs with branching, loops, networks, or a combination thereof) showed the strongest association with the time to tumor growth in a Cox proportional hazard model. CONCLUSIONS: The characteristics of our patient cohort are comparable by clinical and echographic parameters with cohorts for predicting tumor growth, described previously in the literature. In addition, we detected a novel clinical predictor of tumor growth: the confocal ICG angiographic detection of complex MCPs.

Adult↗

PubMed1998

Doxorubicin induced expression of P-glycoprotein in a canine osteosarcoma cell line.

Canine and human osteosarcoma are very similar with respect to clinical presentation, radiological and histopathological features, metastatic rate and pattern and response to therapy. For these reasons, canine osteosarcoma is a useful intermediate model for the disease in humans. Overexpression of P-glycoprotein, the product of the MDR1 gene, is the most important predictor of an adverse clinical course in human patients with osteosarcoma. Exposure of canine osteosarcoma cells to doxorubicin resulted in overexpression of MDR1 mRNA and P-glycoprotein. Furthermore, these cells failed to accumulate doxorubicin intracellularly and were less sensitive to vincristine-induced cytotoxicity as compared to parental cells.

ATP Binding Cassette Transporter, Subfamily B, Mem↗

PubMed1995

An analysis of radiotherapy in the management of 104 patients with parotid carcinoma.

A retrospective analysis was made of 104 patients with parotid carcinoma treated with radical radiotherapy between 1977 and 1986. Eighty-seven patients received postoperative radiotherapy and 17 had radiotherapy alone. The 5- and 10-year survival figures, corrected for intercurrent deaths, were 60% and 49% respectively, with primary control rates of 68% and 58%. Local control was significantly better for patients initially presenting with T1/T2 disease, but local relapse still occurred in 23% of these patients. Of 13 patients with acinic cell tumours, four developed local recurrence and a further two had metastatic disease. These patterns of relapse suggest that patients with parotid carcinoma should receive postoperative radiotherapy irrespective of disease stage or histological type.

Adolescent↗

PubMed2001

Comparison of German language versions of the QWB-SA and SF-36 evaluating outcomes for patients with prostate disease.

BACKGROUND: The quality of well-being scale (QWB) and the Medical Outcome Study 36-item short form (SF-36) are alternative methods for measuring general health outcomes. Few studies compare these approaches against one another and no studies have compared German language versions. METHOD: A German language version of the self-administered quality of well-being scale (QWB-SA) was developed using forward and back translation methods. The German QWB-SA and a German language version of the SF-36 were administered to clinical population groups with current diagnoses of prostate cancer, benign hyperplasia of the prostate, colon cancer, and rectal cancer. Data were obtained from four German clinics. In addition to the quality of life measures, data on cancer stage and disease state were obtained. RESULTS: The QWB-SA and SF-36 were highly correlated. The QWB-SA was systematically related to disease state. Those with no symptomatic evidence had the highest scores followed by those who were stable with no metastatic disease and those with metastatic progression. Similar patterns were found for most SF-36 scales although the SF-36 failed to discriminate between those with no evidence of disease and those with stable disease without metastasis. CONCLUSIONS: Both the QWB-SA and SF-36 perform as expected using German language translations. Although both measures differentiate patients with metastasis from those without symptoms, the QWB-SA better differentiated those with no evidence of disease from those with stable disease without metastasis.

Aged↗

PubMed1995

In vivo and in vitro invasion in relation to phenotypic characteristics of human colorectal carcinoma cells.

In this study we investigated the tumorigenicity, growth pattern and spontaneous metastatic ability of a series of nine human colorectal carcinoma cell lines after subcutaneous and intracaecal xenografting in nude mice. CaCo2 cells were found to be poorly tumorigenic to non-tumorigenic in either site; the other cell lines were tumorigenic in both sites. SW1116, SW480 and SW620 did not show local invasive in the NCI-H716 and LS174T cells were both invasive in the caecum, but only NCI-H716 was invasive in the subcutis. HT29 and 5583 (S and E) cells were invasive in the caecum and from that site metastatic to the lungs and/or the liver. HT29 and 5583S cells were both invasive in the subcutis, but 5583E cells were not. Of each category of in vivo behaviour in the caecum, one cell line was further investigated with regard to invasion in vitro (into embryonic chick heart fragments), E-cadherin expression in vivo and in vitro and in vitro production of u-PA and t-PA. These parameters were chosen in view of their purported role in extracellular matrix degradation and intercellular adhesion, which are all involved in the invasive and metastatic cascade. Invasion in vitro was not predictive for invasion or metastasis in vivo. In the cell line which showed invasion in embryonic chick heart tissue, heterogeneous E-cadherin expression was observed in vitro together with a relatively high production of u-PA. The non-invasive cell lines showed in vitro homogeneous expression of E-cadherin with a relatively low production of u-PA. In vivo expression of E-cadherin was either absent or heterogeneous. We conclude that: (1) colorectal carcinoma xenografts show site-specific modification of in vivo invasive and metastatic behaviour; (2) invasion in vitro does not correlate with invasion and metastasis in vivo; (3) in vitro non-invasion might be associated with homogeneous E-cadherin expression and low production of u-PA; (4) E-cadherin expression in vitro differs from E-cadherin expression in vivo. The results support the notion that the microenvironment in which cancer cells grow is one of the factors involved in the regulation of invasive and metastatic behaviour.

Animals↗