SEARCH · PubMed Health
Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
A patient with oat cell carcinoma had circulating carcinoma cells, which initially suggested a diagnosis of acute leukemia. The correct diagnosis was made only by histopathologic examination of the bone marrow. A case of a similar bone marrow disorder, which developed after diagnosis of oat cell carcinoma, is also presented.
Circulating tumor cells can be detected by means of flow cytometry in the blood of mice bearing i.m. Lewis lung carcinoma. This technique can be applied in the case of aneuploid tumors and does not require either concentration of nucleated cells or other processing of the blood samples. It offers the advantages of simplicity and speed and allows quantitative measurement of the number of circulating tumor cells. It can be applied to the study of the effects of drug treatment on the number of circulating tumor cells, for those drugs which do not cause alterations in the nuclear DNA content of normal diploid blood cells. The number of circulating tumor cells determined by flow cytometry is markedly reduced by treatment with ICRF-159, by dimethyltriazene DM-COOK, and also by its clinically used analog, DTIC.
The objectives of this study were to assess whether the use of two reverse transcription-PCR (RT-PCR) cDNA assays and multiple blood sampling increased circulating tumor cell detection in colorectal cancer patients. Systemic blood was sampled three times at 1-min intervals in 100 colorectal cancer patients (50 primary tumors only and 50 liver metastases), and in 70 control patients without known cancer. After removal of the erythrocytes, samples were subjected to separate RT-PCR reactions using specific primers for carcinoembryonic antigen (CEA) and cytokeratin 20 (CK20). Statistical analysis was performed by the two-sample binomial test and the one-sided McNemar test. There were significant increases in circulating tumor cell positivity when CEA and CK20 assays were used together as compared with either CEA or CK20 assay used alone. There were also significant increases in circulating tumor cell positivity for either CEA or CK20 assay used alone when the results from two blood samples were compared with the results from one sample. Circulating colorectal cancer cell positivity rose from 48% (CEA) and 34% (CK20) with one assay of one sample to 74% when both assays of three samples were used to identify circulating tumor cells. Three non-cancer control patients (4.3%) were positive for either CEA (two patients) or CK20 (one patient). Tumor cells were identified more frequently in the circulation of colorectal cancer patients than had been suggested previously. RT-PCR-based studies of the clinical significance of circulating cancer cells in colorectal cancer should involve multiple blood samples with identification of multiple tumor-related cDNA products.
BACKGROUND: Tumourous invasion into the portal circulation is a frequent and typical complication of primary carcinoma of the liver. No imaging method can, however, assess unequivocally the biological nature of the vascular occlusion and rule out reliably the possibility of benign thrombosis. The objective of the present work was to evaluate the yields of percutaneous thin-needle aspiration biopsy for the verification of intraluminal growth of a tumour, which influences to a considerable extent decisions and possible subsequent therapeutic provisions. METHODS AND RESULTS: Aspiration biopsy of the thrombus was performed in 33 patients with an ultrasonographically apparent occlusion of the portal circulation associated in 29 observations with primary carcinoma of the liver and in four instances with secondaries in the liver. For puncture thin needles--0.8-0.9 mm (21-20 G) were used inserted under ultrasonographic control. The presence of tumourous cells in the portal vessels was proved in 31 patients, i.e. in 94%. An oncologically negative result of biopsy was recorded in one patient with primary carcinoma of the liver and in a female patient with secondaries. Among morphologically verified tumourous occlusions complicating primary carcinoma of the liver a multinodular variant of a tumour was found in 11 observations and a solitary form (mean size of the focus 9 cm) in 10 observations. In 7 patients the vascular occlusion and positive result of biopsy revealed the existence of a diffuse infiltrating type of tumour. In the histological structure of the tumour which was assessed in 13 primary carcinomas of the liver differentiated types of neoplasms predominated unequivocally (10 cases) over non-differentiated tumours (3 cases). CONCLUSIONS: Thin-needle aspiration biopsy is a highly sensitive method for the detection of vascular expansion of liver tumours. It can be used successfully and without risk to assess staging of the disease where necessary.
Following the injection of B16 melanoma cells into the portal veins of mice, all animals developed liver tumors, but only 16% developed lung tumors. Portal vein injections of radiolabelled B16 and Walker 256 cancer cells into mice and rats, respectively, revealed that all of the cells were temporarily arrested in the liver and most were then slowly released. Bioassays indicated that of 8 X 10(4) B16 cells released from the liver over 24 h after portal vein injections of 10(5) cells, only approximately 1% were delivered to the lungs in a viable state. Experiments made with radiolabelled B16 cells showed that transit through either the liver or lungs following portal vein or tail vein injections, respectively, resulted in massive death of cancer cells. It is suggested that the death of most circulating cancer cells passing through the first organ encountered after leaving their primary tumor, serves to severely limit their further direct spread to other organs. It is therefore expected that metastases to these other organs would, to a large extent, be generated by cancer cells from metastases in the "first organs" as distinct from direct seeding from cancer cells released from the primary tumor. If the results of the present experiments have general application, they serve to emphasize the importance of metastasis of metastases in the natural history of the spread of cancer. In a previous publication (Weiss, 1980), studies of lung-to-liver traffic of cancer cells in rats revealed that, after tail vein injections, most Walker 256 cells were temporarily arrested in the pulmonary vasculature and then slowly released. A large proportion of the released cancer cells were dead or lethally injured on release from the lungs, and this "first organ processing" apparently accounted for the comparative rarity of extrapulmonary tumors following tail vein injections. In this communication, the concept of "first organ processing" of circulating cancer cells is further examined with respect to the liver-to-lung traffic of B16 melanoma and Walker 256 cells injected into the portal veins of mice or rats respectively. Both of these cell types grow well in the lungs following tail-vein injection.
PURPOSE: To examine the utility of guanylyl cyclase C (GC-C)-specific nested reverse transcriptase polymerase chain reaction (RT-PCR) to detect circulating tumor cells in patients with colorectal cancer. PATIENTS AND METHODS: Peripheral-blood mononuclear cells from 24 patients with Dukes' stage D colorectal cancer were analyzed by GC-C-specific nested RT-PCR using 1 microg of total RNA. Peripheral-blood mononuclear cells from 20 healthy volunteers served as controls. Additionally, peripheral-blood CD34+ progenitor cells were assayed for the expression of both GC-C and other epithelial cell-specific markers. RESULTS: GC-C mRNA was detected in blood mononuclear cells from all 24 patients with colorectal cancer and all healthy volunteers. These unexpected positive results reflected low-level ectopic transcription of GC-C in CD34+ progenitor cells. Moreover, CD34+ progenitor cells expressed other epithelial cell-specific markers, including prostate-specific antigen, prostate-specific membrane antigen, carcinoembryonic antigen, CK-19, CK-20, mucin 1, and GA733.2. Limiting the quantity of mononuclear cell total RNA analyzed to < or = 0.8 microg eliminated detection of GC-C and other tissue-specific transcripts in blood of healthy volunteers. However, under the same conditions, GC-C mRNA was detected in mononuclear cells from all 24 patients with metastatic colorectal cancer. Using 0.5 microg of total RNA and GC-C-specific primers, nested RT-PCR detected a single human colon carcinoma cell (approximately 20 to 200 GC-C transcripts/cell) in 10(6) to 10(7) mononuclear blood cells. CONCLUSION: These data suggest that GC-C may be useful for detecting circulating colorectal cancer cells. They also demonstrate that CD34+ cells are a source of ectopically expressed epithelial cell-specific markers and that CD34+ cells may contribute to the high false-positive rate generally observed when those markers are used to detect rare circulating metastatic cancer cells by RT-PCR.
BACKGROUND: Renal cell carcinoma (RCC) is characterized by von Hippel-Lindau gene inactivation and vascular endothelial growth factor (VEGF) overproduction. The mechanism of VEGF overproduction may involve protein kinase C (PKC) delta and zeta isoforms. UCN-01 (7-hydroxystaurosporine) is a selective inhibitor of PKC. Given the historically low objective response rate in RCC, time to disease progression (TTP) as an alternative endpoint was employed to evaluate the antitumor activity of UCN-01 in RCC. METHODS: Patients with progressive, metastatic RCC received UCN-01 intravenously on Day 1 of each 21-day cycle. The initial dose was 90 mg/m(2) and all subsequent doses were 45 mg/m(2) unless modified for toxicity. TTP was the primary endpoint, defined as the period from the first day of treatment until disease progression. Detection of circulating EpCAM-positive renal carcinoma cells was undertaken for predictive or prognostic potential. RESULTS: Twenty-one patients were enrolled in this Phase II study. Accrual was halted after failure to reach a predetermined efficacy requirement with 7 patients remaining disease progression free after 4 months (6 cycles). The median TTP for all patients was 2.67 months (range, 0.4-7.6 months). There were no objective responses. Therapy was generally well tolerated. Thirteen patients had < 0.6 EpCAM-positive cells/mL (considered negative) at all time points measured. Two patients had detectable EpCAM-positive cells at a single time point with other measurements being negative. CONCLUSIONS: TTP is a novel endpoint for the evaluation of agents in RCC. UCN-01 did not demonstrate significant antitumor activity. No evidence for significant circulating EpCAM-positive cells was found in this study cohort.
Patients who receive peripheral blood stem cell transplants are at risk of developing cancer recurrence due to the presence of malignant cells in the transplants. We investigated a sensitive method to detect malignant cells in the peripheral blood and peripheral blood stem cells of patients with testicular cancer using nested, reverse transcription-polymerase chain reaction (RT-PCR) to measure alpha-fetoprotein gene expression. Using this technique, a single cancer cell could be detected in 10(6) peripheral blood mononuclear cells. This is the first report of an attempt to detect circulating malignant cells in the peripheral blood of patients with testicular cancer by nested RT-PCR.
The only hope of long-term survival for patients with hepatocellular carcinoma (HCC) is surgical resection or liver transplantation. However, recurrence or metastasis formation is common after surgery. We aim to assess whether surgical resection leads to hematogenous dissemination of malignant and nontumor hepatocytes and determine the quantity and timing of hepatocyte shedding into the circulation. Using semiquantitative reverse transcription-PCR for alpha-fetoprotein (afp) and albumin (alb) mRNAs, we measured the mass of malignant and nontumor hepatocytes in 53 peripheral blood samples collected preoperatively, intraoperatively, and postoperatively from 13 HCC patients. We compared these data with those in 54 control samples collected from 24 healthy subjects and patients with chronic hepatitis/cirrhosis and 10 hepatocellular adenoma patients who underwent resection. Clinicopathological information of HCC patients was obtained during 3-year follow-up. In 100% (23 of 23) of HCC and adenoma patients, alb mRNA levels increased 10-10(6)-fold intraoperatively and then markedly declined within 8 weeks after operation. Levels of afp mRNA increased 5-7600-fold preoperatively in 8% (1 of 13) and postoperatively in 70% (9 of 13) of HCC patients. All five HCC patients with persistently elevated afp mRNA levels died from intrahepatic/extrahepatic metastasis, liver recurrence, or persistent HCC within 1 year after surgery. The absence/clearance of afp mRNA in 75 % (six of eight) of survivors was strongly associated with the absence of metastasis/recurrence (P = 0.02). We present evidence that alb-expressing hepatocytes are released intraoperatively into the circulation, and afp-expressing tumor cells are disseminated mostly postoperatively that may potentially be the source of recurrence or metastasis. Sequential quantification of both alb and afp mRNAs may provide insights for risk assessment and prognostic indication.
Early detection of recurrence is valuable for monitoring hepatocellular carcinoma (HCC) progression. By quantitative reverse transcriptase polymerase chain reaction (RT-PCR), we derived calibration curves for alpha-fetoprotein (afp) and albumin (alb) mRNAs using 40 matched tumors and non-tumor liver tissues from HCC/adenoma patients. We prospectively quantified tumor cells and non-tumor liver cells in 62 patients' blood samples before, during and after surgery. Expression of both mRNAs was heterogeneous (1-10(5)-fold) between tumors and HepG2 cell line. The alb-mRNA levels in non-tumor liver cells were 2-10-fold higher than in tumor cells. The afp-mRNA levels in HCC cells were 30-1000-fold higher than in non-tumor cells. The alb-mRNA level in blood may reflect the number of liver cells, whereas the afp-mRNA level may represent mostly the number of HCC cells. We found different ratios of circulating HCC cells to non-tumor liver cells during the clinical course of patients, in association with the subsequent development of recurrence/metastasis. This approach may prove useful for detecting and monitoring HCC progression.
We have investigated whether liver resection and needle liver biopsy cause dissemination of liver cells into peripheral blood circulation, using a reverse-transcription polymerase chain reaction (RT-PCR)-based assay targeted against alpha-fetoprotein (AFP) mRNA. Twelve patients with and 16 without primary liver cancer (PLC) undergoing liver resection were tested before skin incision, after liver mobilization, after hepatic parenchyma transection, after abdominal wall suture, and 4 days after surgery. Two patients with and 20 without PLC were tested before, 20 minutes after, and 24 hours after needle liver biopsy. Six of 14 patients with and 0 of 36 patients without PLC scored positive before intervention (P <.001). Liver cell spreading was induced at different times after surgery and liver biopsy in 14 of 14 patients with but also 23 of 36 without PLC (P <.05). We conclude that liver resection and needle liver biopsy induce release of cells from the liver, which are not necessarily liver tumor cells, into the peripheral blood circulation. This may be, however, an important mechanism of liver cancer cell dissemination deserving further investigations.
Adhesion molecules and stromal cell-derived factor-1 (SDF-1)/CXCR4 signaling play key role in homing and mobilization of hematopoietic progenitor (HPC) and hematopoietic cancer clonogenic cells (HCC). High expression of VLA-4 is required for homing of HPC and HCC, whereas downregulation of these molecules is required for successful mobilization of HPC and HCC. Upregulation and activation of the SDF-1/CXCR4 signaling is required for homing of HPC and HCC, whereas disruption of the SDF-1 signaling is required for mobilization of HPC and HCC. Hence, mobilizations of HPC and HCC occur concurrently. It is proposed that drug resistance evolves as a result of repeated cycles of chemotherapy. Following each cycle of chemotherapy, HCC lose adhesion molecules and SDF-1 signaling. Surviving cells, released from tumor sites, circulate until re-expression of adhesion molecules and CXCR4 occurs, then homing to stroma of distal tissues occurs. Cytokines secreted by cells in the new microenvironment induce proliferation and drug resistance of HCC. This process is amplified in each cycle of chemotherapy resulting in disease progression. A novel model for treatment is proposed in which circulating HCC are the target for clinical intervention, and concurrent treatment with chemotherapy and antilineage-specific antibodies will result in abrogation of the 'vicious cycle' of conventional anticancer therapy.
PURPOSE: We previously developed a quantitative system for the detection of cytokeratin 19 (CK-19) transcripts using reverse transcriptase polymerase chain reaction (PCR) to detect breast carcinoma cells in blood and bone marrow. The aim of this study was to determine the value of this system in monitoring patients with metastatic disease and to compare it with an established immunocytochemical method. PATIENTS AND METHODS: Patients with progressive, locally advanced, and metastatic breast cancer (all stage IV) who were due to start systemic treatment were recruited. Blood samples were analyzed for CK-19 transcripts using quantitative PCR (QPCR) and immunocytochemistry (ICC) throughout their course of treatment. RESULTS: One hundred forty-five blood samples were obtained from 22 patients over 13 months. Seventy-two (49.6%) of these samples were positive by QPCR, and 56 (42%) of 133 were positive by ICC. Of the 133 specimens analyzed by both techniques, 95 (71.4%) had the same results for each, and of the 71 samples that were positive, 40 (56%) were positive by both methods. The relationship between the number of cells detected and the QPCR values was statistically significant (P <.0001). Of the 25 courses of assessable treatment, 17 (68%) of 25 treatment outcomes (either response or disease progression) were reflected by QPCR measurements, and 12 (57%) of 21 were reflected by ICC. During the course of the study, five patients showed a response, and of these, ICC was in agreement in four cases (80%) and QPCR in three cases (60%). Eighteen courses of treatment resulted in progression of the disease; however, only 15 of these were assessable by ICC. ICC was in agreement in eight (53%) of 15 of these cases, and QPCR in 15 (83%) of 18 cases. CONCLUSION: Circulating carcinoma cells are frequently found in patients with metastatic breast cancer. In the majority of patients, cancer cell numbers as evaluated by QPCR or ICC reflected the outcome of systemic treatment.
We attempted to detect circulating hepatocellular carcinoma by demonstrating hepatocyte-associated mRNA in the nuclear cell component of peripheral blood using nested reverse transcription-polymerase chain reaction because of the extremely small number of tumor cells in the circulation. Albumin mRNA was demonstrated not only in the liver tissue (hepatocytes) and HepG2 cells but also in nuclear cells of the blood from normal healthy volunteers (neutrophils and lymphocytes) by reverse transcription-polymerase chain reaction. In contrast, alpha-fetoprotein mRNA was demonstrated in the liver tissue, as well as in HepG2 cells, but not in peripheral blood of normal healthy volunteers, indicating the possibility of using alpha-fetoprotein mRNA for detection of benign and malignant hepatocytes among the population of neutrophils and lymphocytes. alpha-Fetoprotein mRNA in peripheral blood was detected in 17 of 33 cases of hepatocellular carcinoma (52%), 2 of 13 cases of cirrhosis (15%) and 2 of 17 cases of chronic hepatitis (12%). alpha-Fetoprotein mRNA was not demonstrated in 26 cases of normal healthy volunteers (0%). Among the patients with hepatocellular carcinoma, total volume of tumor tissue, maximum size of tumor and serum alpha-fetoprotein level were markedly increased in the patients with alpha-fetoprotein mRNA in blood. In addition, alpha-fetoprotein mRNA was detected in the blood of all 6 patients showing metastasis at extrahepatic organs (100%), in contrast to 11 of 27 cases without metastasis (41%). From these results, we conclude that the presence of alpha-fetoprotein mRNA in peripheral blood may be an indicator of circulating malignant or benign hepatocytes, which might predict hematogenous spreading metastasis of tumor cells in patients with hepatocellular carcinoma.
Virtually every modality employed in the treatment of cancer has demonstrated an adverse effect upon metastasis under some conditions. This review surveys the experimental and clinical literature pertaining to the untoward effects of ionizing radiation upon metastatic processes. Two processes are described: (1) enhancement of metastases following local tumor irradiation; (2) localization of metastasis in previously irradiated normal tissues. In the first process the experimental evidence indicates a local effect of irradiation upon the tumor-stroma interface. It predominates under conditions of non-curative radiation doses. There is no proof that this process occurs in clinical practice, but a review of data provides suggestive evidence for its existence following non-curative therapy. The second process is documented both experimentally and clinically. It requires the presence of viable, circulating tumor cells and appears mediated through vascular damage. The few clinical reports suggest that this effect is rare in practice. The clinical significance of both processes appears small under conditions of effective tumor therapy, but it is speculated that inadequate tumor irradiation, or irradiation of normal tissues with uncontrolled tumor elsewhere, may be deleterious.
We prospectively analyzed the circulating tumor burden in colorectal cancer patients using semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) for carcinoembryonic antigen (CEA) and cytokeratin 19 (CK19 ). We distinguished the mRNA levels in peripheral blood between 33 patients and 26 healthy controls with reference to SK-BR-3 cell line. We found CEA-mRNA in 88% of patients and 92% of controls, and CK19 mRNA in 64% of patients and 19% of controls. Our CK19 mRNA assay was sufficiently sensitive to detect one SK-BR-3 cell among 10(6) normal blood cells. The upper limit of CK19 mRNA among controls was exceeded by 14 patients, and 12 patients (86%) developed systemic metastases/recurrence. Significantly elevated CK19 mRNA levels appeared to originate from circulating malignant cells (P<0.0001). Of relevance, the CK19 mRNA level increased with advancing Dukes' stage and correlated directly with the serum CEA level (P=0.016). CK19 mRNA quantification may prove valuable for cancer staging and disease monitoring.
At present, sampling of the lymph nodes or bone marrow for the detection of regions of metastatic disease in patients with breast cancer can only be undertaken at the time of initial diagnosis and surgery. However, the sampling of these tissues and the methods used are inaccurate, time consuming, and cannot be used for easy routine screening to determine disease recurrence and response to treatment. Because of the problems encountered with current methods and tissues sampled at the time of breast cancer diagnosis, this review discusses the urgent requirement for and potential development of a quick, simple, and accurate diagnostic test utilising the haematogenous system, a source of circulating tumour cells in patients with breast cancer, and highly sensitive molecular biological techniques, such as reverse transcription polymerase chain reaction. In addition, this review also highlights potential problems that may be encountered and should be avoided when devising such a test.
The hyaluronan (HA) receptor CD44 has a well documented role in tumour metastasis. This review focuses on the potential significance of CD44 expression and function in regulating the metastasis of both haematological malignancies and solid tumours to the bone. Specifically, the review will discuss the evidence that HA-CD44 interactions facilitate the arrest of circulating malignant cells upon the bone marrow endothelial cells and discuss data that suggests CD44 may orchestrate the ability of tumour cells to regulate the modification of the bone matrix and support its colonisation by malignant cells.