PLA2 (group IIA phospholipase A2) as a prognostic determinant in stage II colorectal carcinoma.

BACKGROUND: Approximately 30% of all colorectal cancer (CRC) patients are diagnosed with stage II disease. Adjuvant therapy is not widely recommended. However, it is well established that a subgroup of patients with stage II are at high risk for recurrence within their lifetime and should be considered for adjuvant chemotherapy. The present work was designed to assess the value of group IIA phospholipase A2 (PLA2) as a predictor of disease outcome in stage II CRC patients with long-term follow-up. PATIENTS AND METHODS: The present study comprises a series of 116 patients who underwent bowel resection for stage II CRC during 1981-1990 at Turku University Hospital. Archival paraffin-embedded CRC tissue samples were used to prepare tissue microarray blocks for immunohistochemical staining with PLA2. RESULTS: Fifty-five percent of all tumors were positive for PLA2. There was no significant correlation between PLA2 expression and age, sex, depth of invasion and lymph node status. In Kaplan-Meier survival analysis, there was a significant (P = 0.010) difference in disease-free survival (DFS) between patients with negative tumors (longer DFS) and those with positive tumors. The same was true with disease-specific survival (DSS), patients with PLA2-negative tumors living significantly longer (P = 0.025). In multivariate (Cox) survival analysis, however, PLA2 was not an independent predictor of DFS or DSS. In subgroup analysis, the right-sided tumors with negative PLA2 staining had remarkably better prognosis (P = 0.010) than PLA2-positive left-sided tumors. CONCLUSIONS: Quantification of PLA2 expression seems to provide valuable prognostic information in stage II CRC, particularly in selecting the patients at high risk for recurrent disease who might benefit from adjuvant therapy.

DNA image cytometry predicts disease outcome in stage II colorectal carcinoma.

BACKGROUND: Approximately 30% of all colorectal cancer (CRC) patients are diagnosed with stage II disease. Adjuvant therapy is not widely recommended. However, it is well established that a subgroup of patients with stage II are at high risk for recurrence within their lifetime and should be considered for adjuvant chemotherapy. The present work was designed to study the prognostic value of nuclear DNA content in stage II CRC of patients with long-term followup. PATIENTS AND METHODS: Isolated nuclei from 50 microm-thick paraffin sections of tissue samples from 253 patients with stage II CRC, who had undergone bowel resection at Turku University Central Hospital were cytocentrifuged on slides, stained with Feulgen staining, and DNA was measured using a computer-assisted image analysis cytometry system. Different approaches were applied in analysis of DNA histograms. RESULTS: DNA content did not show any relation with age (p < 0.96), sex (p < 0.35), tumor invasion (p < 0.77), or grade (p < 0.31). Aneuploid DNA content was significantly more frequent in the cancer of the left colon and rectum than the right colon (p = 0.02). S-phase fraction analysis revealed that a higher proportion (62%) of the older patients (>65 years) had high proliferation rates than did the younger patients (p < 0.05). Patients with narrow range histograms had a better disease-free survival (DFS) (narrow range: 70%, wide range: 60% at 10 years). Tumors with >9c nuclei were associated with significantly better DFS and disease-specific survival (DSS) as compared with the patients who did not have >9c nuclei in their tumor samples (p < 0.003 and p < 0.0001, respectively). Multivariate survival (Cox) model showed that only classification of the basic pattern of the histogram [odds ratio OR) = 29.14; 95% confidence interval (CI) 2.350-361.57] (p = 0.009) and recurrence (OR = 165.35; 95% CI 48.42-564.7) (p = 0.0001) proved to be independent predictors of clinical outcome. CONCLUSION: Our results seem to suggest it truly is possible, by using DNA cytometry, to find groups with different prognosis among stage II cases. Those with a high recurrence rate should be considered for adjuvant chemotherapy.

Expression of the cell-cell adhesion molecule beta-catenin in colorectal carcinomas and their metastases.

To study the dynamic events leading to impaired cell-cell adhesion upon transition to the invasive phenotype of colorectal cancer (CRC), we examined three distinct beta-catenin expression patterns (membranous, cytoplasmic, and nuclear) in the paired samples of the primary tumours (P) and their metastatic lesions (M). beta-catenin expression was detected by immunohistochemistry (IHC) in 33 pairs of the primary CRC and their metastases. In a pair-wise (P-M) comparison, the membranous index (MI) was significantly different between P and M (p=0.036, Wilcoxon Signed-Ranks test), while cytoplasmic index (CI) and nuclear index (NI) values did not significantly deviate between P and M. MI in primary tumours was inversely related to the patient's age (p=0.04) and tumour grade (p=0.03), while patients with low MI in M had a high rate of metastasis at diagnosis (p=0.06). CI in P was lower in patients with LN involvement (p=0.02) and in advanced tumour stage (p=0.002). Tumours of the ascending colon had the highest CI in their M (p=0.04). Interestingly, high MI of the M lesions was a significant predictor of favourable overall survival (OS) in univariate (Kaplan-Meier) survival analysis (p=0.035). In conclusion, significant aberrations in beta-catenin expression probably take place in CRC cells during the development of metastatic phenotype, but a change from membrane expression to cytoplamic and/or nuclear expression is not a prerequisite for metastasis in all cases.

Comparison of CD44 expression in primary tumours and metastases of colorectal cancer.

A better understanding on the development of a metastatic phenotype in colorectal cancer (CRC) is essential to help identify patients at high risk for metastasis. Therefore, we have studied the role of the CD44 family of trans-membrane glycoprotein in the process of CRC metastasis, by examining the expression of CD44s and CD44v6 in primary tumours and their metastatic lesions in 46 patients using immunohistochemistry. The expression of both CD44s and CD44v6 was significantly higher (moderate/strong) in primary tumours as compared to their metastases (p=0.008, p=0.0001, respectively). CD44s expression in metastases increased with the degree of the histological grade (p=0.009) and invasiveness of the primary tumour (p=0.002). Disease-free survival (DFS) was shorter in patients who had metastases with a strong/moderate expression of CD44s as compared to those with negative/weak expression (8.3 months vs 16.9 months p=0.221, respectively). Our finding that CD44s expression in metastatic lesions may reflect the aggressiveness of the primary tumour from which it has originated implicates an important link between the two lesions. CD44 expression may also provide valuable biological information as suggested by the observation that up-regulated CD44s expression in metastases is associated with a shorter DFS.

Cysteine proteinase inhibitor cystatin A in breast cancer.

Cystatin A (acid cysteine proteinase inhibitor; ACPI) is a natural inhibitor of cysteine proteinases. It has been suggested that an inverse correlation exists between cystatin A and malignant progression. We wanted to assess the biological and clinical significance of cystatin A in infiltrative breast carcinoma by immunohistochemical staining. Formalin-fixed paraffin-embedded material from 440 cases treated during the years 1988-1991 was used in the study. After exclusion of patients with disseminated disease at diagnosis, previous contralateral breast carcinoma, and absence of follow-up data, 384 patients could be included in the survival analysis. For immunohistochemical analysis of cystatin A, we used monoclonal cystatin A antibody WR-23/2/3/3, the binding of which was detected by the avidin-biotin-peroxidase method. Immunohistochemical analysis of Bcl-2 and p53 was also done, and mitotic activity was evaluated. Positive staining for cystatin A was found in 52 of 440 cases. The staining was irregular but showed irrefutably positive areas within neoplastic tissue. Most of the positive tumors were of the ductal infiltrative type, but two were mucinous carcinomas, one medullary and one squamous cell carcinoma. No lobular carcinomas showed positive staining. Focal cystatin A positivity was seen in myoepithelial cells of benign ducts. Occasional apoptotic bodies within the neoplasm showed strong positivity for cystatin A. Tumors positive for cystatin A were of larger size and had higher mitotic activity than cystatin A-negative tumors. Cystatin A was associated with negative Bcl-2 staining, but there was no statistically significant association between axillary lymph node status or p53 immunostaining. The risk for breast cancer-related death was significantly higher in patients with cystatin A-positive tumors than in those with cystatin A-negative ones. The risk increase was significant also in lymph node-negative patients. After adjusting for the effect of tumor size, histological grade, and lymph node status, cystatin A-positive patients still had a higher risk of death. Patients with cystatin A and p53 coexpression had a higher risk of death than the other patients. The findings reveal a new variant of aggressive breast cancer. This type of carcinoma may develop during tumor progression through genetic instability that allows cystatin A expression and gives growth advantage to a clone of tumor cells.

Changes in mitochondrial lipids of rat kidney during ischemia.

Lipid changes in mitochondria isolated from rat kidney after various periods of ischemia were analysed by thin-layer chromatography and gas-liquid chromatography. Free fatty acids were increased at 30 min and more so thereafter. Total phospholipid fatty acids decreased steadily. The proportion of diphosphatidylglycerol (cardiolipin) in the total phospholipid fraction decreased at 30 min, but the proportion of phosphatidylcholine and phosphatidylethanolamine in the total phospholipid fraction did not change until the irreversible phase of ischemic injury. We have shown that decrease of cardiolipin in mitochondrial membrane occurs early during ischemia, and only during the irreversible phase of ischemia are phosphatidylethanolamine and phosphatidylcholine broken down. It is postulated that these phenomena are due to activation of phospholipase in the mitochondrial membrane.

E-cadherin, CD44s and CD44v6 correlate with tumour differentiation in colorectal cancer.

Cell adhesion molecules (CAMs) are cell surface glycoproteins that are important in cell-cell and cell-matrix interactions and play an important role in cell growth and differentiation. We examined immunohistochemically CD44s, CD44v6 and E-cadherin expression in 86 formalin-fixed, paraffin-embedded primary tumours and 5 metastases. Lower levels of CD44s, CD44v6 and membranous E-cadherin expression were significantly associated with higher tumour grade (p=0.022, p=0.016 and p= 0.041, respectively). Moreover, CD44v6 and membranous E-cadherin expression were correlated with the depth of primary tumour invasion (p=0.030 and p=0.020, respectively), and increased expression of CD44v6 and decreased membranous E-cadherin expression were associated with increased primary tumour invasion. The results suggest that these CAMs are associated with tumour differentiation and invasion in locally advanced and metastatic colorectal carcinoma.

A molecular and epidemiological study on bladder cancer: p53 mutations, tobacco smoking, and occupational exposure to asbestos.

In this study, we found an unexpected association (crude odds ratio = 2.8; 95% confidence interval = 0.9-8.4) between definite work-related exposure to asbestos and carcinoma of the urinary bladder in a small group of patients (n = 28) initially recruited as referents for an epidemiological feasibility study on the occupational causes of lung cancer. We extended the study by using molecular methods to examine mutations in the p53 tumor suppressor gene in the same cases of bladder cancers. The same number of archival samples of transitional cell carcinoma, mainly of grade 3, were added to the analysis. We failed to show any association between occupational exposure to asbestos and p53 mutations among bladder cancer patients. We observed an increasing occurrence of p53 mutations in nonsmokers (5 of 17, 29%), former smokers (8 of 21, 38%), and current smokers (9 of 16, 56%) in that order; however, this was not statistically significant. The most prevalent type of mutation was G:C to A:T transition. Tumor grade was not associated with the frequency of mutations, but the higher stage (T3-T4) tumors appeared to have mutations more frequently than did the less invasive tumors (T1-T2).

The role of nucleolar organiser regions as prognostic factors in breast cancer.

Nucleolar organiser regions (NORs) were stained in paraffin-embedded biopsy specimens of 80 female breast carcinomas by the silver (Ag) technique. The patients were prospectively followed up for a mean of 12.4 years (range 11.5-13.3). The number of different types of Ag-NORs was correlated with the histological grade, clinical stage, DNA ploidy, S-phase fraction (SPF) and clinical outcome. Grade III tumours showed higher Ag-NOR counts than low grade tumours. The total number of Ag-NORs (P = 0.0059) and the number of dispersed Ag-NOR (P = 0.0199) were significantly related to DNA ploidy aneuploid tumours showing higher Ag-NOR counts. The number of aggregated Ag-NORs was predictive (P = 0.0413) for the development of metastatic disease during follow-up. On the other hand, crude, cancer-related or recurrence-free survival could not be predicted significantly by the Ag-NORs. The results suggest that the number of Ag-NORs is clearly related to the proliferative activity in breast cancer, but the prognostic value of Ag-NOR counting is inferior to the previously recognised prognostic factors.

Hypomagnesemia due to renal disease of unknown etiology.

A young man, investigated because of tetanic convulsions and arthritic pains, was shown to have hypomagnesemia, hypermagnesuria, hypokalemia, hypercalciuria, progressive nephrocalcinosis and chondrocalcinosis. In this syndrome, renal function was normal except for the abnormal excretion of electrolytes. Renal sodium conservation was normal. Light and electron microscopic studies of renal biopsy specimens showed the presence of several abnormal tubules. Immunofluorescent staining showed deposits of immunoglobulins in the glomeruli and tubules. Magnesium therapy was started under balance study conditions and resulted in decreased calciuria and complete remission of subjective symptoms. The progression of nephrocalcinosis was halted, and there was some decrease in the intra-articular calcium deposits after two years of continuous oral magnesium therapy. The administration of spironolactone decreased urinary magnesium but did not normalize it, whereas triamterene administration was without effect in this respect. The results of the morphologic and electrolyte balance studies are discussed. The patient was found to exhibit several features which have not been described before in connection with hypomagnesemia of unknown origin.

Morphometric grading in breast cancer: thresholds for mitotic counts.

Three hundred sixty-four cases of invasive ductal breast cancer diagnosed during the years 1988 to 1991 were analyzed to determine quantitative thresholds for mitotic activity. Mitotic counts were calculated in each sample and expressed as standardized mitotic index (SMI) and mitotic activity index (MAI). Based on Kaplan-Meier curves, univariate and multivariate analysis of Cox's regression, and maximum efficiencies of ROC analysis, optimal thresholds were determined on the basis of survival and recurrence of disease. In our material, with a follow-up time of 5 years 9 months, we found two thresholds--a lower and a higher--for both SMI (17 mitoses/mm2 and 32 mitoses/mm2) and MAI (13 mitoses/10 HPF and 35 mitoses/10 HPF). The thresholds were the same in the whole material and in subgroups divided according to the patients' age and axillary lymph node status at the time of diagnosis, and tumor size. The thresholds clearly separated patients with favorable, intermediate, and unfavourable outcome of disease. In our material, the risk of breast cancer death associated with the determined thresholds (ranging from 4.7 to 3.8) clearly exceeded those of menopausal status, axillary lymph node status and tumor size. The risk of breast cancer death associated with the determined thresholds was still emphasized in the groups of premenopausal and axillary lymph node-negative patients, and with tumor size less than 2 cm in diameter (risk ratios, 11.8, 6.0, and 6.7, respectively). The results suggest that the presented quantitative thresholds could be applied in grading of invasive ductal breast cancer.

Apoptosis, analysed by means of lamin B detection, correlates with grade of astroglial tumours but not with p27Kip1/retinoblastoma protein expression.

The aim of our study was to correlate apoptosis, assessed by means of lamin B degradation, with grade of tumour and immunohistochemical expression of p27Kip1 and retinoblastoma protein (pRB) in a series of 32 low-grade astrocytomas (LGA) and 43 high-grade astrocytomas (HGA). Determination and analysis of lamin B expression was achieved stereologically with the use of computerised interactive image analysis. The average stereological surface density of the lamin-positive nuclear surface of cells showing evidence of lamin degradation cells was 13.80 mm2/mm3 in LGA and 21.02 mm2/mm3 in HGA. The average range of immunopositivity of p27 and pRB expression was 2.85 and 2.10, respectively, in LGA and 1.80 and 0.88, respectively, in HGA. The rate of apoptosis indirectly correlated with the expression of both p27 and pRB but was not fully significant (P < or = 0.09). Our findings suggest that there may be a loss of function of main cell-cycle regulators and increased uncontrolled cell death in addition to increased cell proliferation in high-grade astrocytomas. Moreover, we believe that the detection of lamin B degradation in astroglial tumours can be an alternative, precise and convenient assay for the detection of a defined set of apoptotic cells. However, before being applied more generally, comparative research should be done on different methods of quantifying apoptosis, with the intent of finding the difference between biologically different methods. Such studies would also be able to find the method associated with the strongest prognostic power.

Nephropathia epidemica: mild variant of hemorrhagic fever with renal syndrome.

The diagnosis of nephropathia epidemica (NE) is primarily not histological, but because biopsy samples sometimes reach the pathologist, knowledge of histology may be of diagnostic value, in addition to clarifying the pathogenesis. The authors collected 80 biopsies from 65 patients taken after the onset of NE from various hospital files in Finland. Light microscopic, morphometric, electron microscopic, and immunohistochemical methods were applied in studying these samples. There was slight tubular dilatation and interstitial edema best evidenced during the first month after the onset of the disease. There was limited electron microscopic evidence of endothelial cell damage or reaction, also in the glomeruli. Occasional tubular necrotic cells or mitoses were found. About half of the cases were positive for IgG or IgM, and C3 and fibrin in the tubular basement membrane. Samples of the recovery phase showed interstitial fibrosis. Medullary interstitial hemorrhages were seen in 60% of samples of the first two weeks after onset. Interstitial inflammatory changes were diffuse in the early phases and often focal thereafter. During the first two weeks there was congestion and mild hypercellularity of the glomeruli. There was also slight prominence of mesangium, and evidence of endothelial cell damage or reaction. Osmiophilic glomerular deposits were scanty. Focal immunoglobulin (usually IgG) and complement deposits were present in the glomeruli, but less intense than in classical glomerulonephritis. Without medullary hemorrhages in the biopsy, the suggestive diagnosis could rest on interstitial edema, diffuse but sparse inflammatory infiltrate, dilatation of occasional tubules, changes suggestive of tubular cell death, and congestion and slight hypercellularity of the glomeruli.

Immunohistochemical staining of CA 50 antigen in human bladder cancer. Relation to histologic grade, clinical stage, and prognosis.

The immunohistochemical detection of tumor marker CA 50 was studied in bladder cancer of WHO grades I-III. The material consisted of tumors in 83 patients and the mean clinical follow-up time was thirteen years (range 9.6-22 years). The fraction of CA 50-positive cells (FPtot) in microscopic image was scored 0-100 percent. Also the maximally staining region was selected, and the fraction of CA 50-positive cells in this region was scored 0-100 percent (FPmax). The average staining intensity of CA 50-positive cells was scored from 0 to 3 in the whole section (ASItot) and in the maximally staining area (ASImax). The inverse relation between histologic grade, FPtot (p = 0.0001), and ASItot (p = 0.006) was statistically significant. FPtot (p = 0.039) and ASItot (p = 0.018) were also inversely related to clinical stage. Occurrence of metastasis during the follow-up was associated with low CA 50 positivity (FPtot, p = 0.003; ASItot, p = 0.002). The lower the staining intensity or the lower the fraction of CA 50-positive cells, the more aggressive was the tumor. In survival analysis, low FPtot (p = 0.002) and ASItot (p = 0.007) values were related to high risk of bladder cancer death. The results show that immunohistochemical staining of bladder tumor specimens with CA 50 can be used to predict bladder cancer aggressiveness and survival.

Axonal reinnervation does not influence Schwann cell proliferation after rat sciatic nerve transection.

We asked whether reinnervating axons are Schwann cell mitogens in vivo as they are in vitro. Left sciatic nerves of 50 Wistar rats were transected. In one-half of the animals, axonal reinnervation from the proximal to the distal stump was allowed to take place, while in the other half, sutures were placed on the transected nerve ends to prevent reinnervation. Samples were collected from 3 days up to 8 weeks after the transection proximally and distally from the point of transection. PCNA-immunostaining was performed on paraffin sections to determine the number of proliferating cells. Axonal reinnervation was followed by Bielschowsky staining and Schwann cell number was determined by counting S-100-immunopositive cells from paraffin sections. In the distal stump Schwann cell proliferation was similar in both experimental groups. There was no statistical evidence of S-100 negative cell proliferation during the study. Proximally to the site of transection the number of small initial axonal sprouts and also the number of Schwann cells increased if the nerve stump had been sutured. In conclusion, although axons may be mitogenic for Schwann cells, axonal reinnervation into the distal stump of the transected peripheral nerve does not influence the proliferation of Schwann cells to a greater extent than other potential effects associated with nerve transection.

Relationship between DNA ploidy and survival in patients with exocrine pancreatic cancer.

The DNA ploidy of pancreatic cancer tissue from paraffin blocks was measured by flow cytometry in 46 patients whose disease had been detected and treated with surgery. Lymph node involvement was observed at the time of diagnosis in 36% of patients with diploid tumors and in 79% of patients with aneuploid tumors (p = 0.017), but no clear relation to metastasis could be observed (p = 0.201). The S-phase fraction (SPF) was significantly higher in aneuploid than in diploid tumors (p = 0.007). All patients who underwent radical surgery had diploid DNA content and SPF below the median (11.5%). Seven patients with a diploid tumor (32%) and none of the aneuploid cases survived 1 year. Over the 1-year period, in order of importance, the type of treatment (p less than 0.001), DNA ploidy (p = 0.004), tumor size (p = 0.0046), and lymph node status (p = 0.027) predicted survival. Aneuploidy showed a significant association with decreased cumulative survival (p = 0.015), and a suggestive relationship with SPF was found. The results suggest that DNA ploidy of pancreatic cancer can be used in dividing the patients into different prognostic groups. The value of the detection of aneuploidy, however, is limited, because diploid pancreatic cancers are also generally rapidly fatal.

A quantitative morphometrical study of neuron degeneration in the substantia nigra in Parkinson's disease.

We studied the pigmented neurons of the substantia nigra (SN) from 8 controls and 20 patients with Parkinson's disease (PD) using a computerized morphometric methodology. On the basis of neuronal topography, several anatomic regions were outlined in the SN. In these subregions the area, perimeter, diameter of the cell bodies and cell numbers were measured and were counted in the controls and PD patients. The measurements were made at the level of the exit of the third cranial nerve from the brain stem. In PD patients, when the whole SN was considered, the mean area, mean perimeter and diameter of the pigmented cell bodies were significantly reduced by 35%, 20% and 21% respectively from the control mean values. Regionally, the pigmented neuron area in the medial ventral part (VM), medial dorsal part (DM), lateral ventral part (VL), lateral dorsal part (DL) and pars lateralis part (PL) showed a significant reduction of 33-41% as compared to controls. In these subregions, a significant decrease in PD patients from the control mean values was seen both in the pigmented neuron perimeter, by 19-26%, and the diameter by 19-25%. This decrease in cell size suggests that, in PD patients, the remaining pigmented neurons in the SN are in a process of degeneration and atrophy. In PD patients the number of pigmented neurons in the whole SN decreased about 76% from control values. Evaluation of the influence of cell size on the apparent quantity of cells in sections indicates, however, that in PD patients the impact of true loss of pigmented neurons is far more dramatic than the impact of their decrease in size.

Correlation between neuromorphometry in the substantia nigra and clinical features in Parkinson's disease using disector counts.

Previous studies based on single sections have suggested a significant correlation between pigmented neuronal loss in the substantia nigra (SN) and clinical features in Parkinson's disease (PD). However, disector (DS) counts-unbiased and accurate stereological estimates have not been available. To evaluate total neuron numbers in the pars compacta of the substantia nigra (SNpc) in relation to clinical features, we estimated the neuron counts in the SNpc by the DS method in brain samples from 12 controls and 12 PD patients. The total number of pigmented neurons in the whole SNpc was significantly reduced in PD patients (to 45% of the control mean, P < 0.001). The density of pigmented neurons (neuron/mm3) was reduced to 51% of the average control value (P < 0.001). No significant difference was seen in the volume (mm3) of the SNpc between PD patients and controls. Furthermore, the total number of pigmented neurons in the SNpc showed a significant negative correlation with the duration of disease (r = -0.86, P < 0.001) and with the stage of disease (r = -0.58, P < 0.05) in PD patients. Using an unbiased neuron counting method, these relationships, for the first time, demonstrate that the more severe pigmented neuronal loss in the SNpc is associated with the longer duration and the more severe stage of disease in PD patients.

A new tumor marker MCA in breast cancer diagnosis.

The serum concentration of the new tumor marker MCA (mucinous carcinoma associated antigen) was determined by an enzyme immunoassay kit method, which is based on the use of a monoclonal antibody b12. The mean MCA values in breast cancer patients (n = 40) were significantly higher than in patients with benign breast disease (n = 55, p less than 0.001) and in control subjects (n = 37, p less than 0.001). When we used the cut-off level 11 KU/l for MCA, 6/37 (16.2%) of control subjects 7/55 (12.7%) of patients with benign breast disease, 18/40 (45.0%) of all breast cancer patients 11/19 (57.9%) of breast cancer patients with axillary node involvement, and 1/1 breast cancer patient with distant metastases were above this cut-off level. For comparison, at the cut-off level of 5 micrograms/l the CEA test was positive in 7/40 (18%) cancer cases, and in 6/19 (32%) of cancer patients with nodal involvement. Patients with axillary nodal metastasis showed higher values than patients without metastasis in both tests (p less than 0.01). The combination of MCA at 11 KU/l cut-off level and CEA at the 5.0 micrograms/l cut-off level reached the diagnostic sensitivity of 0.53, efficiency of 0.73, and specificity of 0.87. It seems that MCA is a promising tumor marker in breast cancer. Especially high values may have diagnostic significance.

Efficient test for cancer antigens: decreased levels of cancer antigen in serum after excision of breast tumor.

Monoclonal antibody technology has developed new serum marker tests which may offer advantages in the follow up of cancer patients. In breast cancer detection among symptomatic patients MCA and CA 15-3 monoclonals at best reach a sensitivity of about 0.45 at a specificity level of 0.90. We have tested these monoclonal tests (MCA and CA 15-3) by applying them to detect the postoperative decrease of marker levels in the serum among women with breast cancer or benign breast disease. The CA 15-3 postoperative decrease test (5% decrease) reached slightly higher diagnostic sensitivity (0.70) and efficiency (0.83) than the MCA postoperative decrease test (sensitivity 0.65, efficiency 0.80). The combined MCA and CA 15-3 decrease tests had a sensitivity of 0.85 and an efficiency of 0.90 at 5% decrease level. The postoperative decrease test is far superior to normal marker tests in breast cancer detection, especially when several sensitive markers are used. A 35% or larger decrease in serum levels of MCA or CA 15-3 after surgery was 100% specific for breast cancer, and detected 43% of all cancer cases. Although such a test cannot be used for screening, it could be valuable in special diagnostic situations.