Application of artificial neural network-based survival analysis on two breast cancer datasets

This paper applies artificial neural networks (ANNs) to the survival analysis problem. Because ANNs can easily consider variable interactions and create a non-linear prediction model, they offer more flexible prediction of survival time than traditional methods. This study compares ANN results on two different breast cancer datasets, both of which use nuclear morphometric features. The results show that ANNs can successfully predict recurrence probability and separate patients with good (more than five years) and bad (less than five years) prognoses. Results are not as clear when the separation is done within subgroups such as lymph node positive or negative.

Computer-generated nuclear features compared with axillary lymph node status and tumor size as indicators of breast cancer survival

The extent to which malignant cells deviate from normal is generally accepted to be a prognostic indicator. However, assessing the degree of deviation has been subjective and poorly reproducible. Our goal is to develop a computer program for objectively measuring nuclear size, shape, and texture from histologic slides and to make the program available on the Internet. We used this program to analyze 353 histologic sections obtained from patients with invasive breast cancer who were diagnosed and treated from 1981 through 1995 and who had determinable outcomes. The median follow-up was 8.3 years. We compared the relationship of survival with our computer-derived nuclear features versus axillary lymph node status and tumor size. We believe that our results are generally applicable because our patient survival, when stratified by lymph node status, was similar to that of the 24,000 breast cancer patients in the National Cancer Institute's Surveillance, Epidemiology, and End Results program. In multivariate analysis, the strongest prognostic factor was the largest nuclear area, followed by tumor size and the extent of axillary lymph node involvement. The mean area of the 3 largest nuclei when combined with tumor size identified 30% of all breast cancer patients who had an 87% 15-year breast cancer-specific survival. Inclusion of lymph node status added little to this 2-factor model. Routine axillary lymph node surgery for prognostic purposes may become unnecessary, because nuclear features may provide sufficient information.

Importance of nuclear morphology in breast cancer prognosis

The purpose of this study is to define prognostic relationships between computer-derived nuclear morphological features, lymph node status, and tumor size in breast cancer. Computer-derived nuclear size, shape, and texture features were determined in fine-needle aspirates obtained at the time of diagnosis from 253 consecutive patients with invasive breast cancer. Tumor size and lymph node status were determined at the time of surgery. Median follow-up time was 61.5 months for patients without distant recurrence. In univariate analysis, tumor size, nuclear features, and the number of metastatic nodes were of decreasing significance for distant disease-free survival. Nuclear features, tumor size, and the number of metastatic nodes were of decreasing significance for overall survival. In multivariate analysis, the morphological size feature, largest perimeter, was more predictive of disease-free and overall survival than were either tumor size or the number of axillary lymph node metastases. This morphological feature, when combined with tumor size, identified more patients at both the good and poor ends of the prognostic spectrum than did the combination of tumor size and axillary lymph node status. Our data indicate that computer analysis of nuclear features has the potential to replace axillary lymph node status for staging of breast cancer. If confirmed by others, axillary dissection for breast cancer staging, estimating prognosis, and selecting patients for adjunctive therapy could be eliminated.

Computer-derived nuclear features compared with axillary lymph node status for breast carcinoma prognosis

BACKGROUND

Both axillary lymph node involvement and tumor anaplasia, as expressed by visually assessed grade, have been shown to be prognostically important in breast carcinoma outcome. In this study, axillary lymph node involvement was used as the standard against which prognostic estimations based on computer-derived nuclear features were gauged.

METHODS

The prognostic significance of nuclear morphometric features determined by computer-based image analysis were analyzed in 198 consecutive preoperative samples obtained by fine-needle aspiration (FNA) from patients with invasive breast carcinoma. A novel multivariate prediction method was used to model the time of distant recurrence as a function of the nuclear features. Prognostic predictions based on the nuclear feature data were cross-validated to avoid overly optimistic conclusions. The estimated accuracy of these prognostic determinations was compared with determinations based on the extent of axillary lymph node involvement.

RESULTS

The predicted outcomes based on nuclear features were divided into three groups representing best, intermediate, and worst prognosis, and compared with the traditional TNM lymph node stratification. Nuclear feature stratification better separated the prognostically best from the intermediate group whereas lymph node stratification better separated the prognostically intermediate from the worst group. Prognostic accuracy was not increased by adding lymph node status or tumor size to the nuclear features.

CONCLUSIONS

Computer analysis of a preoperative FNA more accurately identified prognostically favorable patients than did pathologic examination of axillary lymph nodes and may obviate the need for routine axillary lymph node dissection.

Indeterminate fine-needle aspiration of the breast. Image analysis-assisted diagnosis

BACKGROUND

Fine-needle aspiration (FNA) of the breast, although effective for the diagnosis of breast carcinoma, has a significant drawback. A minority of cases cannot be classified as benign or malignant. These FNAs are assigned an inconclusive diagnosis, often prompting surgical biopsy. Surgery is justified in some of these cases, but many of these lesions are benign. If these inconclusive FNAs could be accurately diagnosed as benign or malignant, many of these patients might avoid having to undergo surgical biopsy.

METHODS

An image analysis and an automated learning system that was developed at the University of Wisconsin (Xcyt) was used to categorize 56 (37 benign and 19 malignant) breast FNAs diagnosed as "indeterminate" and the computer diagnosis compared with the surgical biopsy. For each case, an operator chose a group of cells within a single field on the FNA slide and digitized this image using a video camera. The outline of each nucleus was manually outlined, and the exact border was delineated by the computer. Based on the analysis of three nuclear features (area, texture, and smoothness), the Xcyt system computed a benign or malignant diagnosis and a corresponding probability of malignancy for each case.

RESULTS

Probabilities of malignancy for the respective cases ranged from 0.0-1.0. Benign cases were defined as those having probabilities of malignancy < 0.3; those with probabilities above this limit were considered malignant. Using these criteria, the computer identified 33 cases as benign and 23 cases as malignant. When compared with the surgical biopsy, 42 of the cases (75%) were correctly classified with a sensitivity and specificity of 73.7% and 75.7%, respectively. There were only 5 false-negative cases with a false-negative rate of 13.5% and a predictive value of a negative test of 84.8%.

CONCLUSIONS

When faced with inconclusive diagnoses of FNAs of breast masses, the authors believe that image analysis may be used as an aid in the further classification of such lesions, thereby providing a more appropriate triage for surgical biopsy.

Computer-derived nuclear "grade" and breast cancer prognosis

Visual assessments of nuclear grade are subjective yet still prognostically important. Now, computer-based analytical techniques can objectively and accurately measure size, shape and texture features, which constitute nuclear grade. The cell samples used in this study were obtained by fine needle aspiration (FNA) during the diagnosis of 187 consecutive patients with invasive breast cancer. Regions of FNA preparations to be analyzed were digitized and displayed on a computer monitor. Nuclei to be analyzed were roughly outlined by an operator using a mouse. Next, the computer generated a "snake" that precisely enclosed each designated nucleus. Ten nuclear features were then calculated for each nucleus based on these snakes. These results were analyzed statistically and by an inductive machine learning technique that we developed and call "recurrence surface approximation" (RSA). Both the statistical and RSA machine learning analyses demonstrated that computer-derived nuclear features are prognostically more important than are the classic prognostic features, tumor size and lymph node status.

Computer-derived nuclear features distinguish malignant from benign breast cytology

This article describes the use of computer-based analytical techniques to define nuclear size, shape, and texture features. These features are then used to distinguish between benign and malignant breast cytology. The benign and malignant cell samples used in this study were obtained by fine needle aspiration (FNA) from a consecutive series of 569 patients: 212 with cancer and 357 with fibrocystic breast masses. Regions of FNA preparations to be analyzed were converted by a video camera to computer files that were displayed on a computer monitor. Nuclei to be analyzed were roughly outlined by an operator using a mouse. Next, the computer generated a "snake" that precisely enclosed each designated nucleus. The computer calculated 10 features for each nucleus. The ability to correctly classify samples as benign or malignant on the basis of these features was determined by inductive machine learning and logistic regression. Cross-validation was used to test the validity of the predicted diagnosis. The logistic regression cross validated classification accuracy was 96.2% and the inductive machine learning cross-validated classification accuracy was 97.5%. Our computerized system provides a probability that a sample is malignant. Should this probability fall between 30% and 70%, the sample is considered "suspicious," in the same way a visually graded FNA may be termed suspicious. All of the 128 consecutive cases obtained since the introduction of this system were correctly diagnosed, but nine benign aspirates fell into the suspicious category.(ABSTRACT TRUNCATED AT 250 WORDS)

Computerized breast cancer diagnosis and prognosis from fine-needle aspirates

OBJECTIVE

To use digital image analysis and machine learning to (1) improve breast mass diagnosis based on fine-needle aspirates and (2) improve breast cancer prognostic estimations.

DESIGN

An interactive computer system evaluates, diagnoses, and determines prognosis based on cytologic features derived from a digital scan of fine-needle aspirate slides.

SETTING

The University of Wisconsin (Madison) Departments of Computer Science and Surgery and the University of Wisconsin Hospital and Clinics.

PATIENTS

Five hundred sixty-nine consecutive patients (212 with cancer and 357 with benign masses) provided the data for the diagnostic algorithm, and an additional 118 (31 with malignant masses and 87 with benign masses) consecutive, new patients tested the algorithm. One hundred ninety of these patients with invasive cancer and without distant metastases were used for prognosis.

INTERVENTIONS

Surgical biopsy specimens were taken from all cancers and some benign masses. The remaining cytologically benign masses were followed up for a year and surgical biopsy specimens were taken if they changed in size or character. Patients with cancer received standard treatment.

OUTCOME MEASURES

Cross validation was used to project the accuracy of the diagnostic algorithm and to determine the importance of prognostic features. In addition, the mean errors were calculated between the actual times of distant disease occurrence and the times predicted using various prognostic features. Statistical analyses were also done.

RESULTS

The predicted diagnostic accuracy was 97% and the actual diagnostic accuracy on 118 new samples was 100%. Tumor size and lymph node status were weak prognosticators compared with nuclear features, in particular those measuring nuclear size. Compared with the actual time for recurrence, the mean error of predicted times for recurrence with the nuclear features was 17.9 months and was 20.1 months with tumor size and lymph node status (P = .11).

CONCLUSION

Computer technology will improve breast fine-needle aspirate accuracy and prognostic estimations.

Image analysis and machine learning applied to breast cancer diagnosis and prognosis

Fine needle aspiration (FNA) accuracy is limited by, among other factors, the subjective interpretation of the aspirate. We have increased breast FNA accuracy by coupling digital image analysis methods with machine learning techniques. Additionally, our mathematical approach captures nuclear features ("grade") that are prognostically more accurate than are estimates based on tumor size and lymph node status. An interactive computer system evaluates, diagnoses and determines prognosis based on nuclear features derived directly from a digital scan of FNA slides. A consecutive series of 569 patients provided the data for the diagnostic study. A 166-patient subset provided the data for the prognostic study. An additional 75 consecutive, new patients provided samples to test the diagnostic system. The projected prospective accuracy of the diagnostic system was estimated to be 97% by 10-fold cross-validation, and the actual accuracy on 75 new samples was 100%. The projected prospective accuracy of the prognostic system was estimated to be 86% by leave-one-out testing.

Machine learning techniques to diagnose breast cancer from image-processed nuclear features of fine needle aspirates

An interactive computer system evaluates and diagnoses based on cytologic features derived directly from a digital scan of fine-needle aspirate (FNA) slides. A consecutive series of 569 patients provided the data to develop the system and an additional 54 consecutive, new patients provided samples to test the system. The projected prospective accuracy of the system estimated by tenfold cross validation was 97%. The actual accuracy on 54 new samples (36 benign, 1 atypia, and 17 malignant) was 100%. Digital image analysis coupled with machine learning techniques will improve diagnostic accuracy of breast fine needle aspirates.

Breast cytology diagnosis with digital image analysis

An interactive computer system has been developed for evaluating cytologic features derived directly from a digital scan of breast fine needle aspirate slides. The system uses computer vision techniques to analyze cell nuclei and classifies them using an inductive method based on linear programming. A digital scan of selected areas of the aspirate slide is done by a trained observer, while the analysis of the digitized image is done by an untrained observer. When trained and tested on 119 breast fine needle aspirates (68 benign and 51 malignant) using leave-one-out testing, 90% correctness was achieved. These results indicate that the method is accurate (good intraobserver and interobserver reproducibility) and that an untrained operator can obtain diagnostic results comparable to those achieved visually by experienced observers.

The effects of intermittent progesterone upon tamoxifen inhibition of tumor growth in the 7,12-dimethylbenzanthracene rat mammary tumor model

The development of endometrial cancer is a potential risk during long-term tamoxifen therapy for breast cancer. In order to protect the uterus, progestin treatment has been proposed for these patients. However, within the 7,12-dimethylbenzanthracene-induced rat mammary model, progesterone is known to reverse the antitumor effects of tamoxifen. This study shows that progesterone administered intermittently still reverses the antitumor effects of tamoxifen in this model. This effect of progesterone is not due to a decrease in the tissue levels of tamoxifen, and may be direct, via the progesterone receptor.

Computer-designed expert systems for breast cytology diagnosis

Three expert systems have been developed to diagnose from nine scalar values visually assigned to epithelial cells obtained by breast fine needle aspiration. These expert systems achieved up to 0.98 sensitivity and 0.97 specificity. When applied to 804 breast masses, the clinical sensitivity was 0.98 and specificity was 0.93 (exclusive of the 0.04 unsatisfactory aspirates). Cancers can be missed physically during the aspiration process; thus, some clinically suspicious masses were biopsied despite benign cytology. This contributed to the difference between the expert system and clinical specificities.

Surgical options in 424 patients with primary breast cancer without systemic metastases

Mastectomy was dictated by medical considerations in about 40% of 424 consecutive patients who had invasive breast cancer with no evidence of systemic metastases. Half of the women considered suitable for local excision of the breast cancer followed by radiotherapy (conservation) elected to have mastectomy, and intraoperative findings dictated mastectomy in about 20% of those electing conservation. Consequently, conservation was accomplished in about one quarter of those treated for breast cancer. Younger rather than older women more frequently expressed the desire for breast conservation.

Multisurface method of pattern separation for medical diagnosis applied to breast cytology

Multisurface pattern separation is a mathematical method for distinguishing between elements of two pattern sets. Each element of the pattern sets is comprised of various scalar observations. In this paper, we use the diagnosis of breast cytology to demonstrate the applicability of this method to medical diagnosis and decision making. Each of 11 cytological characteristics of breast fine-needle aspirates reported to differ between benign and malignant samples was graded 1 to 10 at the time of sample collection. Nine characteristics were found to differ significantly between benign and malignant samples. Mathematically, these values for each sample were represented by a point in a nine-dimensional space of real variables. Benign points were separated from malignant ones by planes determined by linear programming. Correct separation was accomplished in 369 of 370 samples (201 benign and 169 malignant). In the one misclassified malignant case, the fine-needle aspirate cytology was so definitely benign and the cytology of the excised cancer so definitely malignant that we believe the tumor was missed on aspiration. Our mathematical method is applicable to other medical diagnostic and decision-making problems.

Mastectomy or breast conservation in the management of primary breast cancer: psychosocial factors

A diagnosis of breast cancer causes significant emotional, social, and vocational upheaval which diminishes over time. However, newly diagnosed breast cancer patients are mentally capable of making treatment decisions and should be offered the available treatment options. A significant proportion of patients who have the option of breast conservation will choose mastectomy instead. Saving the breast does not significantly alter adjustment problems.

Computer-aided diagnosis of breast aspirates via expert systems

Two computer-driven expert systems trained to correctly diagnose 369 fine needle aspirates of the breast on the basis of nine cytologic descriptive parameters were tested on 70 newly obtained aspirates (57 benign and 13 malignant). The system generated by multisurface pattern separation misclassified one malignant test sample (i.e., one false negative) while the system generated by a connectionist algorithm (neural network) misclassified two benign test samples (i.e., two false positives). A decision tree misclassified three of the benign test samples (i.e., three false positives). These expert systems aid in the cytologic diagnosis of breast aspirates and can serve as models for other applications.

Adjuvant trial of 12 cycles of CMFPT followed by observation or continuous tamoxifen versus four cycles of CMFPT in postmenopausal women with breast cancer: an Eastern Cooperative Oncology Group phase III study

A prospectively controlled randomized trial to compare the adjuvant efficacy of 12 cycles of cyclophosphamide, methotrexate, fluorouracil, prednisone, and tamoxifen (CMFPT) followed by observation or a total of 5 years of continuous tamoxifen versus four cycles of CMFPT followed by observation in postmenopausal women with operable node-positive breast cancer was started by the Eastern Cooperative Oncology Group (ECOG) in 1982. In 1986 the study was modified to allow patients on CMFPT X 12 plus continuous tamoxifen to be rerandomized after completing 5 years of tamoxifen to either continue for life or to stop therapy. Patients were stratified for number of involved nodes and estrogen-receptor (ER) status and randomized to receive one of three treatments: CMFPT X 4, CMFPT X 12, or CMFPT X 12 plus continuous tamoxifen. Of 962 patients entered on the study, 803 were eligible. Life-threatening toxicity occurred in 75 and lethal toxicity in seven patients. Median follow-up is 4.1 years; 279 patients had recurrent disease. Time to relapse (TTR) is significantly longer for patients on CMFPT X 12 plus continuous tamoxifen than for CMFPT X 4 (P = .002), or CMFPT X 12 (P = 0.05). Differences between four or 12 cycles of CMFPT are not significant; relapse-free rates at 5 years are 61% for CMFPT X 12 plus continuous tamoxifen, 51% on CMFPT X 12, and 52% on CMFPT X 4. Treatment differences in overall survival are not significant. Hormone receptor status and number of involved nodes were found to be significant prognostic parameters.

Cosmesis and local control after irradiation in women treated conservatively for breast cancer

One hundred twenty-two patients (124 tumor sites) with breast carcinoma (T1 to T3, N0 to N2, M0) were treated by a lumpectomy and radiation therapy at the University of Wisconsin, Madison, from June 1978 to December 1986. Irradiation to the breast and regional lymph nodes was carried out with cobalt 60 teletherapy in 2-Gy fractions to 50 Gy, followed by an additional boost of 10 Gy to the tumorectomy site with coned electrons. Cosmesis was analyzed by scoring the effects of surgery, as well as the effects of irradiation, and by photographic assessment. After a follow-up of 24 to 119 months (median, 36 months), 82% of the patients were found to have good or excellent cosmetic scores. There was a trend that favored better cosmetic results in younger patients and in patients with outer-quadrant lesions. No significant impact of adjuvant chemotherapy on the cosmetic outcome or on the complications of treatment was demonstrated. There were six local recurrences (5.2%), three of which were true recurrences and the other three that were new primary tumors; 11 distant failures (9%) occurred. The following side effects from irradiation developed in only 5 patients (4.1%): match-line fibrosis (n = 2), soft-tissue necrosis (n = 1), and persistent tenderness (n = 2). The conditions of the two patients with persistent tenderness responded favorably with conservative management. We concluded that a lumpectomy, followed by radiation therapy, provides good cosmetic results without compromising the local control rate. If adjuvant chemotherapy is planned, we recommend that it be administered before radiation therapy in favor of concomitant therapy with both modalities.

Fine-needle aspiration for breast mass diagnosis

Our accuracy in diagnosing 464 solid breast masses by fine-needle aspiration was enhanced by a statistically based algorithm for distinguishing between benign and malignant epithelial cells. Epithelial cells were obtained from 378 breast masses by fine-needle aspiration; nonepithelial cells considered diagnostic of benign conditions were obtained from 66 breast masses, and 19 aspirations were considered unsatisfactory. Excluding one benign cystosarcoma, the algorithm gave 3 false-negative diagnoses and 16 false-positive diagnoses with 211 benign and 167 malignant samples. The overall clinical performance measures for the 444 masses from which diagnostic fine-needle aspirations were obtained and excluding the cystosarcoma were 0.98 sensitivity, 0.94 specificity, and 0.92 positive predictability. Masses diagnosed as benign by fine-needle aspiration can be followed up clinically. Intraoperative frozen section is needed before definitive surgery to determine invasion and confirm the diagnosis of some cytologically malignant masses.

Psychosexual adaptation to breast cancer surgery

Disturbances associated with a breast cancer diagnosis were defined when psychological assessments from 63 patients with a known breast cancer diagnosis were compared to those from 56 patients with an as yet undiagnosed malignancy. Subsequent assessments from the 56 patients with an undiagnosed breast cancer showed disturbances after they saw a physician compared with the assessments from 72 similar patients ultimately diagnosed as benign. Apprehension apparently arose from clues given before a biopsy was done even though the cancer was not yet diagnosed. Compared with the benign breast disease group, the disturbances in patients suspected or diagnosed with breast cancer were found chiefly in assessments of mood and adjustment, and less in assessments of more durable characteristics of personality, psychopathology, and sexual behavior. Psychological problems associated with breast cancer decreased over time, but residuals persisted for at least 16 months postoperatively. Few differences were found between 41 patients who elected breast-conserving surgery and 78 who were treated with mastectomy. Problems were not eliminated by operations which saved the breast.

Diagnostic schemes for fine needle aspirates of breast masses

A comparison was made of four statistically based schemes for classifying epithelial cells from 243 fine needle aspirates of breast masses as benign or malignant. Two schemes were computer-generated decision trees and two were user generated. Eleven cytologic characteristics described in the literature as being useful in distinguishing benign from malignant breast aspirates were assessed on a scale of 1 to 10, with 1 being closest to that described as benign and 10 to that described as malignant. The original computer-generated dichotomous decision tree gave 6 false negatives and 12 false positives on the data set; another tree generated from the current data improved performance slightly, with 5 false negatives and 10 false positives. Maximum diagnostic overlap occurred at the cut-point of the original dichotomous tree. The insertion of a third node evaluating additional parameters resulted in one false negative and seven false positives. This performance was matched by summing the scores of the eight characteristics that individually were most effective in separating benign from malignant. We conclude that, while statistically designed, computer-generated dichotomous decision trees identify a starting sequence for applying cytologic characteristics to distinguish between benign and malignant breast aspirates, modifications based on human expert knowledge may result in schemes that improve diagnostic performance.

Adjunctive chemotherapy as an alternative to ovarian ablation in premenopausal women with carcinoma of the breast

The beneficial effects observed from adjunctive chemotherapy in premenopausal women with carcinoma of the breast may be due only to ovarian ablation. Beneficial effects of chemotherapy induced amenorrhea was noted in four of five reported adjunctive trials. Chemotherapy appears to delay recurrence but has only minimal effect on survival rates. The results of four of five studies comparing ovarian ablation with controls show a consistent, but modest, prolongation of disease-free survival rates from oophorectomy similar to that observed from adjunctive chemotherapy. The benefits are accomplished with less morbidity from ovarian ablation. Additional trials are needed to prove whether or not chemotherapy is more beneficial than adjunctive ovarian ablation in delaying recurrence and if either prolong survival time. Such trials should compare intensive adjunctive chemotherapy with either minimal or no adjunctive therapies. Therapy to be given at the time of recurrence should be defined at the outset to assure comparable over-all treatment among groups.

Statistical approach to fine needle aspiration diagnosis of breast masses

A statistical algorithm was used for recursively partitioning a consecutive series of 37 benign and 69 malignant fine needle aspirates to produce a decision tree for diagnosing breast masses. Optimal separation between benign and malignant cytology was accomplished by evaluating clump characteristics when clumps were present and evaluating cell integrity when clumps were absent. The 1.5% false-negative and 9.7% false-positive rates obtained through this scheme are better than those reported for most series.

Factors influencing options in primary breast cancer treatment

Primary breast cancer treatment is determined by tumor factors and by patient preference. Breast cancer treatments that preserve the cosmetic appearance of the breast are appealing and effective for appropriately selected patients; long-term survival following tumor excision and breast irradiation appears to be comparable to that for mastectomy. Since April 1981, when a protocol was developed and treatment options were offered, factors influencing treatment selection have been analyzed in 206 consecutive primary breast cancer patients. Mastectomy was dictated by tumor-related factors in 96 patients (47%); 110 patients (53%) had the option of mastectomy or conservation--tumor excision plus radiotherapy to the breast. Among these 110 eligible patients, 54 chose conservation (49%) and 56 chose mastectomy (51%). Intraoperative findings for ten patients electing conservation necessitated mastectomy, so conservation was accomplished for 44 (21%) of those treated for breast cancer. Beginning in July 1982, breast cancer patients took a battery of psychosexual assessments before any operation (Profile of Mood States [POMS], Health Locus of Control Scale [HLCS] Locke-Wallace Marital Adjustment Test [MAT], Psychosocial Adjustment to Illness Scale [PAIS], Derogatis Sexual Function Inventory [DSFI], Millon Clinical Multiaxial Inventory [MCMI], and a Breast Cancer Information Test [BCIT]). Comparisons of psychologic and demographic variables were made between patients who chose mastectomy and those who chose conservation. No demographic variable was statistically significantly related to choice, although older women tended to select mastectomy more than younger women. Compared with those who elected conservation, women who elected mastectomy were more tense and anxious (P less than .01), more introverted (P less than .01), felt more depressed and dejected (P less than .05), and reported more sexual problems (P less than .05). Those who elected conservation valued their physical appearance more highly (P less than .01) and were generally more self-interested (P less than .05). Mastectomy was dictated by medical considerations for approximately half of patients with breast cancer. Among candidates for breast conservation, the importance of retaining the breast appeared to be determined to a significant degree by measurable psychological factors.

Antiproliferative effects of interferons on human melanoma cells in the human tumor colony-forming assay

The human tumor colony-forming assay (HTCFA) is an in vitro test that has been used to predict the activity of anticancer drugs against a patient's tumor. We utilized the assay to analyze the antiproliferative effects of seven interferons (IFNs) against 40 human melanomas to determine which IFN had the greatest antiproliferative activity in this drug-resistant tumor. IFNs studied included recombinant IFN-alpha 2; human lymphoblastoid IFN; IFN-alpha Cantell; native beta RPMI; two recombinant IFNs-beta; and recombinant IFN-gamma. Growth was sufficient [greater than 30 tumor colony-forming units (TCFU)/well] for assessing the antiproliferative effects of at least one IFN in 25 tumors (63%). A dose-response relationship was demonstrated by all IFNs in tumors in which some activity was observed (p less than or equal to 0.01). Individual melanomas differed in their sensitivities to the various IFNs. Overall, however, none of the IFNs was markedly more effective in antiproliferative effects than any other, although there was a trend toward IFN-beta ser having more potent antiproliferative properties when compared to IFN-alpha 2 (p = 0.055). Twelve of 13 tumors exposed to combinations of IFN-beta ser and IFN-gamma demonstrated a synergistic antiproliferative effect. In all but two of these, low concentrations of each IFN (less than or equal to 50 U/ml), when combined, resulted in 85-95% inhibition. As prolonged exposure to high concentrations of IFN are often not clinically tolerable, these data suggest that IFN combinations may be one way of achieving more clinically meaningful IFN doses, schedules, and regimens, provided antiproliferative effects are of importance in vivo.

Systematic optimization of the clonal growth of human primary breast carcinoma cells

Human breast carcinomas have been one of the most difficult tumor types to culture in agar-based clonogenic assays. This fact has limited their clinical applicability. We have used statistically motivated experimental designs to systematically improve the clonal culture of enzymatically monodispersed primary human carcinoma cells in an anchorage-independent agar system. Based upon an initial comparison of two basal media, we selected one which gave the best colony growth and then sought to optimize the individual additives in the medium. Hydrocortisone, fetal bovine serum, and red blood cells all improved both plating efficiency and median size of colonies derived from breast carcinoma cells. Next, the concentrations of these three components were simultaneously idealized using response surface methodology. By these methods, it was found that the optimal concentration of hydrocortisone was 0.35 microgram/ml, fetal bovine serum was 6.5%, and red blood cells was 2.1 X 10(7) cells/ml. Using these culture conditions, we have achieved plating efficiencies of 0.39% and 0.19% for colonies with diameters greater than 50 (50 cells) or 70 (130 cells) micron, respectively.

Psychological distress among women with breast problems

Visiting a physician for evaluation of a breast problem which could be cancer is often assumed to be a highly stressful experience. This study evaluates the degree of emotional distress in women about to undergo examination for signs or symptoms of breast disease. Three hundred twenty-two women who attended the Breast Problem Clinic of the Wisconsin Clinical Cancer Center were studied. Each patient completed standard self-administered psychologic tests to evaluate mood disturbance (Profile of Mood States [POMS]) and responsibility taken for overall health care (Health Locus of Control [HLCS]). Results of these tests were compared to control populations of normal college women and female psychiatric outpatients. The women seen in the Breast Problem Clinic were significantly less distressed on POMS subscales which measure depression, anger, fatigue, and confusion than both psychiatric outpatients and normal college women (P less than 0.001). A second group of 17 women who were seen in the hospital 24 to 48 hours before definitive breast cancer surgery were also studied. Women evaluated as inpatients before breast cancer surgery were more distressed than the women attending the outpatient clinic on most POMS subscales, but were not clearly different from normal college women. No differences between the groups were seen for the HLCS. These data indicate that emotional distress among women attending a breast problem clinic is not extraordinary, but that emotional distress heightens when the diagnosis of breast cancer is known.

Radiation survival of human mammary carcinoma cells: criteria for an agar-based clonogenic assay

A human in vivo-in vitro model for breast cancer has been developed based on culture methods that were systematically optimized for solid breast carcinomas. A V-79 cell clonal agar-based model was used to define the analysis problem encountered with agar based clonogenic survival assays. Based on this, we established methods for the generation and analysis of the survival of primary and recurrent breast carcinomas following irradiation. Four out of five primary breast carcinomas studied had similar radiation-cell survival curves. The fifth tumor was more radioresistant. Interestingly, a recurrent breast carcinoma arising in a heavily irradiated chest wall was no more radioresistant than our series of unirradiated primary carcinomas. These methods may be useful both for the study of the radiobiology of human neoplasms and for customizing the treatments and prognosis of individual patients.

Establishment and characterization of human colorectal cancer cell lines

A protocol for establishment of human colorectal carcinoma cell lines from fresh surgically removed tissues is described. Twelve human colorectal carcinoma cell lines were established from 6 of 18 primary cancers and four of four metastases. Cell lines from concurrent primary tumors and metastases were established from two individual patients. Two primary cancers gave rise to multiple cell lines with differing biological characteristics. Factors contributing to our success appear to be differential selection on the basis of substrate adherence and the timing of passage. The protocol avoids the use of feeder layers or passage through athymic mice. The established cell lines exhibit a range of karyotypes, morphologies, and growth characteristics.

A comparison of methods for the production of monodispersed cell suspensions from human primary breast carcinomas

Production of monodispersed cell suspensions from primary human breast tumors is difficult due to the predominant stromal composition of most breast tumors. Our studies were designed to optimize dispersion of breast tumors of known stromal content and histopathology. In a first series of experiments three enzymatic protocols were compared to disperse minced tissue: (A) treatment with collagenase (2 mg/ml) in the presence of 5% serum for 24 hours; (B) treatment with collagenase (6 mg/ml) and DNase (0.002%) in 10% serum for 3 hours; (C) treatment with collagenase (2 mg/ml) for 3 hours followed by pronase (0.075%) for 1 hour. Protocol A produced better cell yields than B or C for all tumors tested. The monodispersed cells were suspended in a 0.3% semi-solid agar with alpha modified Eagles medium (alpha MEM), 10% serum, and selected hormones, then layered over similarly enriched 0.5% semi-solid agar. The cells prepared by protocol A had a higher plating efficiency and larger average colony size than B or C. In a second series of experiments, protocol A was repeated and compared to two additional procedures: (D) treatment with collagenase (2 mg/ml) and hyaluronidase (1 mg/ml) in the presence of 5% serum for 24 hours; and (E) mechanical disaggregation. Protocol D exhibited a small but significant negative difference from A, while E was the least efficient in producing viable monodispersed cells from the tumors. All enzymatically monodispersed cells produced clonal growth in our agar system. However, mechanically dispersed cells gave growth in only 4 of 7 tumors. Protocol A, in addition to yielding the highest number of viable cells per gram of tissue, gave the highest plating efficiency of all protocols tested.

Thymidylate synthetase activity and fluorouracil sensitivity of human colonic cancer and normal mucosal tissue preparations

This study compares thymidylate synthetase activity and certain aspects of fluorinated pyrimidine metabolism in tissue preparations derived from human colonic adenocarcinoma and from normal colonic mucosa. The purpose was to define differences that might be sufficient to explain the selective antitumor response of some colonic adenocarcinomas to 5-fluorouracil (FU) chemotherapy. Some carcinomas had much greater thymidylate synthetase activity than did other carcinomas and all normal mucosal preparations. Such carcinomas may be highly reliant on thymidylate synthetase and hence susceptible to its inhibition. Similarly, the smaller amount of FdUMP dephosphorylation found in all carcinomas compared with autologous normal mucosal preparations might result in prolonged thymidylate synthetase inhibition. In addition, greater thymidylate synthetase inhibition was produced by 1 X 10(-4) M FU in an occasional tumor than was found in normal mucosal preparations.

Enhancement by thymidine of 5-fluorouracil's inhibition of thymidylate synthetase in human tumors

The effects of thymidine (TdR) on the conversion of 5-fluorouracil (5-FU) to 5-fluoro-2'-deoxyuridine-5'-monophosphate and the resulting inhibition of thymidylate synthetase was determined in crude, human tissue extracts. TdR alone has no effect but it augmented the inhibition of thymidylate synthetase produced by 5-FU. TdR augmentation was probably mediated either by increasing 5-FU conversion to 5-fluoro-2'-deoxyuridine-5'-monophosphate or by inhibiting 5-FU catabolism.

Pharmacokinetics of fluorouracil in humans

A high-pressure liquid chromatography method has been used to investigate the pharmacokinetics of fluorouracil after single i.v. doses to patients. The method is simple and is specific for fluorouracil. No interference was observed in fluorouracil determinations due to other administered medication. Plasma levels of fluorouracil declined rapidly after dosing. The mean half-life was 11.4 min, and drug was essentially cleared from plasma in 1 hr. Individual differences in plasma fluorouracil levels, and also in derived pharmacokinetic constants, were considerably less than those reported previously.

The study of burn wound edema using dichromatic absorptiometry

Burn wound edema is a source of major morbidity and mortality. To quantitatively study this edema, we have devised a noninvasive method called Dichromatic Absorptiometry (DA) which is precise (2-3%) and accurate (r equal to 0.99) in measuring changes in tissue fluid. A scanning technique using a dual photon source, 125I and 241Am, is used. The variable attenuation of the two photon energies allows for selective mass measurements of fluid, protein, lipid, and bone. In limbs with thermal injury the correlation of DA changes in fluid mass with circumference was (r equal to 0.97), but DA was more sensitive. In deep second- and third-degree burns, edema formation was maximum between 12 and 18 hours postburn with 80% of maximum already present at 4 hours. Resorption was complete by 1 week in second-degree burns, but significantly delayed in third-degree burns. Superimposed infection produced persistent edema.

Binding of colonic tissue membrane to mononuclear peripheral blood leukocytes

Colonic tissue membrane binding to peripheral blood mononuclear leukocytes was quantitated by 125I labeling of membrane fragments and by determining the acquisition of membrane-specific enzyme activity and radioactivity in mononuclear cells after contact with the tissue membrane fragments. Mononuclear cells bound equal amounts of normal and tumor tissue membrane fragments. Mononuclear cells capable of binding homologous but not autologous colonic tissue membranes were recovered from the peripheral blood of colon cancer-bearing patients. Mononuclear cells capable of binding autologous colonic tissue membranes appeared in the peripheral blood of patients after curative but not palliative tumor resection. Tumor membrane enzymes, including alkaline phosphatase, were introduced to mononuclear cells by bound tissue fragments. The activity of alkaline phosphatase present in the bound membrane fragments was inhibited by the immunorestorative drug, levamisole. Cellular debris liberated from tumors may play an important role in overcoming the host's defenses by binding to mononuclear cells, saturating antigen-binding sites, and introducing exogenous enzymes.

Soft-tissue fluid determination by dichromatic absorptiometry

Dichromatic absorptiometry (DA) in a noninvasive method for individually determining the amount of lipid, bone mineral, and protein and water present in a mixture by differential attenuation of radiation beams emitted from a dual photon source. The physics involved permit these components to be determined extremely accurately and precisely. The present study investigated the ability of DA limb scans to measure changes in total body water produced in dogs and in patients. Dichromatic absorptiometry was determined to be a valid method of measuring changes in total body water content as reflected by limb fluid content changes. Precision was limited by the accuracy in positioning the limb for repeated scanning. Dichromatic absorptiometry has the potential of becoming a clinically useful instrument for measuring fluid content changes in limbs produced either by changes in total body water content or by conditions causing limb edema.