Dose-response in the treatment of breast cancer: a critical review

In animal tumor models the dose-response curve for cytotoxic agents, especially cyclophosphamide, may be steep, but the slope and shape of this curve depends not only on the drug used but on the schedule of drug administration, the specific tumor type, tumor cell kinetics, and tumor mass. It might be anticipated from these studies that the human tumors most sensitive to dose effects would be leukemia, lymphoma, small-cell carcinoma of the lung, and testicular tumors rather than the low growth fraction, relatively less responsive tumors such as breast cancer. However, the clinical evidence for a steep dose-response curve in any tumor type is limited. For breast cancer such evidence is largely retrospective or derived from uncontrolled trials. The data available from randomized trials makes it seem unlikely that small, or even moderate, reductions in drug dose for nontrivial reasons will compromise the survival of patients with either early or metastatic disease. In spite of promising data from small trials, there is, as yet, inadequate evidence to justify the use of very-high-dose therapy and autologous marrow transplant outside the setting of a well-designed clinical trial. The value of high-dose therapy, intensive dose rate, and cumulative drug dose should each be studied in randomized controlled trials.

Comparison of CA15-3 and carcinoembryonic antigen in monitoring the clinical course of patients with metastatic breast cancer

Fifty-three women with metastatic breast cancer and serial plasma samples were selected to study the correlation between disease course and variations in circulating CA15-3 and carcinoembryonic antigen (CEA) levels. Forty-nine patients had their first sample drawn at the beginning of therapy, while four patients did not receive any treatment during the period of study. Clinical course was scored as progressive disease (PD), responsive disease (RD), and stable disease on the basis of radiological and physical evaluations. The percentage of variation in antigen level between the initial sample and samples drawn at the time of the clinical evaluation was correlated with clinical course. CA15-3 levels above 22.0 units/ml and CEA levels above 3.0 ng/ml were considered elevated values. Antigen levels that increased greater than or equal to 25% and decreased greater than or equal to 25% from the initial value were considered to correlate with PD and RD, respectively. Variations in antigen levels +/- 25% from the initial value were considered to correlate with stable disease. Significantly more patients had elevated circulating levels of CA15-3 than CEA (96.2 versus 69.8%; P less than 0.01) at some point in the course of disease. Overall, CA15-3 correlated with disease progression, regression, or stability in a higher number of patients than CEA (60.3 versus 39.6%; P = 0.02). CA15-3 increased greater than or equal to 25% more often than CEA in patients with PD (75.0 versus 58.3%) and decreased greater than or equal to 25% more often than CEA in patients with RD (38.1 versus 23.8%). In a logistic regression model, changes in CA15-3 levels correlated significantly with both PD (P = 0.0004) and RD (P = 0.02), while changes in CEA levels did not (PD, P = 0.34; RD, P = 0.92). Furthermore, correlations obtained when using both antigens together failed to improve the results obtained with CA15-3 alone. The present study thus demonstrates that CA15-3 is more useful than CEA in monitoring the clinical course of patients with metastatic breast cancer.

Genetically determined polymorphism of the circulating human breast cancer-associated DF3 antigen

The murine monoclonal antibody (MAb) DF3 was prepared against a human breast carcinoma. Previous studies have demonstrated that DF3 antigen levels are elevated in plasma of patients with breast cancer. Furthermore, MAb DF3 reacts with circulating glycoproteins of different molecular weights ranging from approximately 300 to 450 kd. The present study demonstrates that plasma DF3 antigen is comprised of at least four moieties with slow (S), intermediate (I), rapid (R) and very rapid (VR) electrophoretic mobilities. The electrophoretic mobility patterns for circulating DF3 antigen differ among individuals. Moreover, DF3 antigen is detectable in urine, and the electrophoretic mobility of the urinary moieties is similar, but not identical, to that in the plasma. Studies in family members suggest that the electrophoretic heterogeneity of plasma DF3 antigen is determined by codominant expression of multiple alleles at a single locus. This locus may code for the core protein of DF3 antigen. These findings thus identify a genetically determined polymorphism of a circulating tumor-associated glycoprotein.

Effect of radioiodination on the binding of monoclonal antibody DF3 to breast carcinoma cells

The murine monoclonal antibody (MAb) designated DF3 is an IgG1 prepared against a membrane enriched fraction of human breast carcinoma. MAb DF3 reacts with a family of large molecular weight glycoproteins expressed by 78% of breast cancer cells and 95% of epithelial ovarian cancer cells. Binding to the breast cancer cell line, MCF-7, of native MAb DF3 was compared to that of MAb DF3 exposed to different concentrations of Iodogen or Bolton-Hunter reagent. The amount of MAb DF3 required to obtain half-maximal binding (B1/2max) with MCF-7 extract for native MAb DF3 IgG was 180 ng, while the B1/2max for MAb DF3 IgG exposed to 1 and 10 micrograms Iodogen was 580 ng and 1800 mg, respectively. In contrast, the B1/2max for MAb DF3 IgG treated with Bolton-Hunter reagent was not different from that for native MAb DF3 IgG. Similar results were obtained with F(ab')2. Immunoreactive fractions for the 125I-labeled MAb DF3 were 0.13, 0.24 and 0.65 for IgG after exposure to 1 microgram Iodogen, 10 micrograms Iodogen and Bolton-Hunter, respectively. Immunoreactive fractions for F(ab')2 were 0.08, 0.08, and 0.53 for 1 and 10 micrograms Iodogen and Bolton-Hunter reagent, respectively. Association constants (Ka) were significantly higher for MAb DF3 IgG radioiodinated with Bolton-Hunter (3.97 +/- 0.38 x 10(8) M-1) than for IgG exposed to 1 microgram Iodogen (2.78 +/- 0.30 x 10(8) M-1) or 10 micrograms Iodogen (1.03 +/- 0.12 x 10(8) M-1). Similarly, the Ka ratio observed for the F(ab')2 radioiodinated with Bolton-Hunter reagent, 1 or 10 micrograms Iodogen was 22 to 3 to 1.(ABSTRACT TRUNCATED AT 250 WORDS)

Primary radiation therapy for locally advanced breast cancer

The optimal local-regional treatment for patients with Stage III breast cancer has not been determined. To evaluate the effectiveness of radiation therapy as local treatment for such patients, the results of 192 patients (five with bilateral disease) treated with radiation therapy without mastectomy between July 1, 1968 and December 31, 1981 were reviewed. Excisional biopsy (gross tumor removal) was performed in only 54 of the 197 breasts. Patients typically received 4500 to 5000 cGy in 5 weeks to the breast and draining lymph nodes; a local boost to areas of gross disease was delivered to 157 patients. Multi-agent chemotherapy was given to 53 patients. The median follow-up was 65 months. The actuarial probability of survival for the entire group was 41% at 5 years and 23% at 10 years. The probability of relapse-free survival (RFS) was 30% at 5 years and 19% at 10 years. The addition of multi-agent chemotherapy was associated with a significantly improved 5-year RFS (40% versus 26%, P = 0.02). The 5-year survival rate was 51% for patients who received adjuvant multi-agent chemotherapy and 38% for patients who did not (P = 0.16). The actuarial rate of local-regional tumor control (not censored for distant failure) for all patients was 73% at 5 years and 68% at ten years, and the crude incidence of local-regional control was 78%. Local-regional tumor control was principally influenced by radiation dose. Patients who received 6000 cGy or greater to the primary site had a better 5-year rate of control in the breast than did patients who received less than 6000 cGy (83% versus 70%, P = 0.06). Significant complications were seen in 15 patients (8%); these included moderate or severe arm edema in six patients and brachial plexopathy in four patients. Cosmetic results at last evaluation were excellent or good in 56% of evaluable patients, fair in 25%, and poor in 19%. It is concluded that high-dose radiation therapy without mastectomy is an effective means of controlling local-regional tumor in patients with locally advanced breast cancer.

Reactivity of monoclonal antibody DF3 with a high molecular weight antigen expressed in human ovarian carcinomas

We have previously described the monoclonal antibody (MAb) DF3, prepared against a human breast carcinoma. MAb DF3 reacts with a high molecular weight glycoprotein detectable in human breast carcinomas and in human milk. Previous studies have demonstrated that DF3 antigen levels are elevated in the plasma of patients with breast and ovarian cancer. The present study has further examined the reactivity of MAb DF3 with human ovarian carcinomas. Immunoperoxidase staining demonstrated reactivity of MAb DF3 with 95% of benign, borderline, and malignant tumors (serous, mucinous, and endometrioid) of the ovary. Furthermore, malignant tumors contained cytoplasmic DF3 antigen while benign tumors expressed the antigen only on apical surfaces. Western blot analyses demonstrated that the MAb DF3 reactive ovarian antigen (DF3-O) was a glycoprotein with a heterogenous molecular weight ranging between 300,000 and 450,000. This antigen was detectable by immunofluorescence on the cell surface of five of six cultured human ovarian carcinoma cell lines. The extent of cell surface reactivity with MAb DF3 was equivalent to or greater than that obtained with MAb OC125, an antibody generated against coelomic epithelium and developmental amnion. Furthermore, uptake of 125I-labeled MAb DF3 by human ovarian carcinoma xenografts in athymic mice was 5.4- and 6.2-fold higher than the respective uptake noted in liver and control tumor (P = 0.031). These findings suggest that DF3-O antigen is similar if not identical to the antigen detected in human breast carcinomas by MAb DF3. Thus, MAb DF3 may be a useful reagent in immunodiagnostic evaluation of patients with ovarian cancer.

Comparison of circulating CA15-3 and carcinoembryonic antigen levels in patients with breast cancer

An immunoradiometric assay (IRMA) has been used to determine circulating levels of the breast cancer-associated antigen, CA15-3. Of 1,050 normal control subjects, serum from 99 (9.4%) had CA15-3 antigen levels greater than 22 U/mL, while that from 58 (5.5%) and 14 (1.3%) had levels greater than 25 U/mL and 30 U/mL, respectively. In contrast, 115 of 158 patients (73%) with metastatic breast cancer had CA15-3 levels greater than 22 U/mL. Thirteen of 26 patients (50%) with only local metastases, 27 of 34 (79%) of those with only bone metastases, and 20 of 24 (83%) with hepatic metastases had CA15-3 levels greater than 22 U/mL. Furthermore, nine of 31 patients (29%) with primary breast cancer had CA15-3 levels greater than 22 U/mL. CA15-3 and carcinoembryonic antigen (CEA) levels were compared for the same patient population. Significantly more patients with metastatic breast cancer had elevated CA15-3 levels than had elevated CEA levels (P less than .001). Furthermore, the CA15-3 IRMA was more sensitive than the CEA assay in patients with only bone metastases, as well as those with only local metastases. Significantly more patients with primary carcinoma of the breast also had elevated CA15-3 than had elevated CEA levels (P less than .02). CA15-3 levels were greater than 22 U/mL in patients with nonmalignant conditions, including five of 25 patients (20%) with benign breast diseases, and 23 of 52 patients (44%) with benign liver diseases. Furthermore, CA15-3 levels were also greater than 22 U/mL in 24 of 54 patients (44%) with gastrointestinal (GI) malignancies, 12 of 17 patients (71%) with bronchogenic carcinoma, and 29 of 44 patients (66%) with epithelial ovarian carcinoma. Serial CA15-3 levels correlated with clinical disease course. Nineteen of 21 patients (91%) with tumor progression had at least a 25% increase in CA15-3 levels. Conversely, seven of nine patients (78%) with tumor regression had at least a 50% decrease in CA15-3 levels. Among 27 patients with stable disease, 16 (59%) had levels that did not vary by more than +/- 25% of the original CA15-3 levels. These results indicate that the CA15-3 antigen is a sensitive marker for the evaluation and monitoring of patients with breast cancer.

The syndrome of inappropriate antidiuretic hormone secretion associated with induction chemotherapy for squamous cell carcinoma of the head and neck

Two patients with squamous cell carcinoma of the head and neck are reported in whom the syndrome of inappropriate antidiuretic hormone (SIADH) secretion occurred transiently during the rapid cytolytic phase of tumor destruction after chemotherapy with cis-platinum diamminedichloride and bleomycin. Immunoperoxidase staining for ADH of the original biopsy specimens from both patients was negative. Possible mechanisms for and the implications of the production of SIADH in this setting are discussed.

Pharmacokinetics of radiolabeled monoclonal antibody B6.2 in patients with metastatic breast cancer

Thirteen patients with metastatic breast carcinoma were given injections of 50-1593 micrograms of 131I-monoclonal antibody (MAb) B6.2 immunoglobulin G and F(ab')2 for pharmacokinetic evaluation and radioimmunoimaging. Blood clearance of the 131I-MAb-B6.2 was biphasic. The mean half-times (t 1/2 alpha, t 1/2 beta) for the immunoglobulin G were 3.5 +/- 1.7 and 20.9 +/- 11.0 h, respectively. The t 1/2 alpha for the F(ab')2 was 1.7 +/- 1.3 h, and the t 1/2 beta was 31.0 +/- 5.7 h. The percentage of protein bound 131I for the immunoglobulin G and for the F(ab')2 at 72 h was 73.7 +/- 11.4% and 58.2 +/- 14.5%, respectively. In vitro reactivity of MAb B6.2 with granulocytes isolated from normal subjects and patients was demonstrated by cytofluorometric and radioimmunoassays. MAb B6.2 was shown to bind with normal cross-reacting antigen, a cell surface antigen known to be expressed on normal human granulocytes. Reactivity with normal cross-reacting antigen on granulocytes is consistent with the skeletal images obtained during immunoscintigraphy of all 13 patients. A specific tumor image was observed in one patient. No toxicity was encountered. In spite of extensive preclinical data suggesting that 131I-MAb B6.2 would be a useful agent for radioimmunoimaging, the clinical utility of this reagent is probably limited because of the reactivity with granulocytes.

Circulating DF3 and CA125 antigen levels in serum from patients with epithelial ovarian carcinoma

The murine monoclonal antibody (MAb), designated DF3, reacts with a 300-kilodalton (kd) mammary epithelial antigen. A sequential double-determinant enzyme-linked immunoassay (EIA) has been developed to monitor circulating DF3 antigen. Previous studies have demonstrated that the use of the DF3 EIA provides a new and potentially useful marker to follow the clinical course of patients with metastatic breast cancer. In the present study, we have monitored circulating DF3 antigen in the serum of patients with epithelial ovarian carcinomas and non-ovarian gynecologic malignancies. Twenty-one of 45 patients (47%) with ovarian carcinoma had elevated DF3 antigen levels (greater than or equal to 30 U/mL). In contrast, three of 20 patients (15%) with non-ovarian gynecologic malignancies, and only four of 59 control women (7%) had elevation of circulating DF3 antigen. The difference between DF3 antigen values from patients with ovarian cancer and from controls was significant (P less than .001). The elevation of circulating DF3 antigen in ovarian cancer patients has also been confirmed by transblot assays. MAb DF3 reactivity occurred predominately with circulating antigens of molecular weights (mol wt) ranging from 300 to 450 kd. Furthermore, DF3 antigen levels have been shown to correlate with progression of disease in six patients with ovarian cancer and after resection of disease in two others. The half-life of circulating DF3 antigen was approximately 45 to 60 days. The results also demonstrate that DF3 antigen is distinct from CA125, a glycoprotein associated with coelomic epithelium and developmental amnion. The use of both the DF3 EIA and the immunoradiometric assay previously described to detect circulating CA125 suggests that determining levels of both markers may enhance the sensitivity of monitoring the course of ovarian cancer. Furthermore, the use of both assays may be useful in distinguishing ovarian cancer from other malignancies.

Use of a murine monoclonal antibody for detection of circulating plasma DF3 antigen levels in breast cancer patients

The murine monoclonal antibody (MAb), designated DF3, reacts with a 300,000-mol wt mammary epithelial antigen. A sequential double-determinant radioimmunoassay (RIA) has been developed to monitor circulating DF3 antigen. Using this assay, we have demonstrated that 33 of 36 normal women had plasma RIA antigen levels less than 150 U/ml. In contrast, 33 of 43 patients (76%) with metastatic breast cancer had RIA DF3 antigen levels greater than or equal to 150 U/ml. The difference between these two groups was statistically significant (P less than 0.001). Similar results have been obtained with a double-determinant enzyme-linked immunoassay (EIA). Only 6 of 111 age-matched normal subjects had EIA DF3 antigens levels greater than or equal to 30 U/ml, while 42 of 58 patients (72%) with breast cancer had levels equal to or above this value. Thus, similar patterns of specificity are obtained with the EIA or RIA. The elevation of circulating DF3 antigen levels in breast cancer patients has been confirmed by transfer blot assays. MAb DF3 reactivity occurred predominantly with circulating antigens of three different molecular weights ranging from 300,000 to approximately 400,000 mol wt. We also demonstrate that patients with both primary and metastatic breast cancer who were free of detectable disease at the time of sampling have DF3 antigen levels that are similar to those obtained from normal subjects. While patients with hepatoma (27%) and ovarian carcinoma (47%) also had elevated circulating DF3 antigen levels, the results suggest that DF3 antigen levels may be useful in distinguishing breast cancer patients from those with esophageal, gastric, colorectal, pancreatic, and lung carcinomas. Furthermore, the results of the RIA, EIA, and transblot analyses demonstrate that the measurement of circulating DF3 antigen levels provides a new and potentially useful marker to follow the clinical course of patients with metastatic breast cancer.

Takayasu's arteritis of the upper extremities. A case report and review of literature

Takayasu's Arteritis is an inflammatory process of the large arteries. It most commonly involves the aorta and its major branches. It is characterized by acute and chronic inflammation and fibrosis of the vessel wall with resultant constriction or occlusion of the vessel lumen. There are various histopathologic stages this disease evolves through which may complicate the diagnosis. In this study we present a case of Takayasu's Arteritis involving the right axillary artery, with a literature review.

Clinical experience with carotid stump pressure and EEG monitoring to determine shunt placement during carotid endarterectomy

The authors' experience with selective shunting during carotid endarterectomy utilizing electroencephalographic and stump pressure measurements is reported. No postoperative neurological deficits occurred in this group of selectively shunted patients. EEG appeared to offer no significant benefit in the management of the patients. Carotid stump pressures alone were reliable in providing the basis for selective shunting.

Supradiaphragmatic right liver lobe and gallbladder

Descriptions of supradiaphragmatic liver lobules have been previously described in diaphragmatic hernia reviews. A unique case of an otherwise anatomically normal, congenitally positioned right liver lobe and gallbladder in a supradiaphragmatic position with no previous history of trauma was encountered.

The quantitation of carbamino adduct formation of angiotensin II and bradykinin

The two equilibrium constants that define the extent of carbamino adduct formation with amines for all values of pH and PCO2 are determined for the alpha-amino groups of the peptide hormones angiotensin II(AII) and bradykinin (BK) by nuclear magnetic resonance techniques. From these constants the variation of carbamino adduct formation has been calculated over the pH range 6.60--8.00 with variable PCO2, and the results are superimposed upon standard pH-bicarbonate diagrams. PCO2, and the results are superimposed upon standard pH-bicarbonate diagrams. The mole fraction, Z, of carbamino adduct form of AII or BK shows a maximum variation in going from metabolic alkalosis, Z congruent to 0.30, to metabolic acidosis, Z congruent to 0.02, with Z near 0.2 for normal acid-base conditions. Adduct formation to hormone may alter the biological effect of the hormone (a) by limiting proteolysis, particularly at the amino-terminal, (b) by altering hormone binding affinity to specific receptors, or (c) by converting the hormone to an antagonist which binds to receptor but does not activate subsequent metabolic events. The requirements for any of these mechanisms to operate are examined in terms of simple equilibrium considerations, and experimental evidence of inhibition of an aminopeptidase model system is presented. These results are consistent with the hypothesis that regulation of some physiological processes through formation of carbamino adduct of peptide hormones is possible.

Methylation of glucagon, characterization of the sulfonium derivative, and regeneration of the native covalent structure

The methylation of the single methionine residue of glucagon is accomplished at a pH of 3.5 in 8 M urea with methyl iodide. The reaction product is a soluble sulfonium derivative, S-methylglucagon, which can be isolated in a highly purified form. This derivative is characterized by amino acid analysis and its effect on the adenylyl cyclase system of rat liver plasma membranes. S-Methylglucagon does stimulate the adenylyl cyclase system; however, its activity is approximately 500 times less than that observed with the native hormone. The solubility of this derivative is great enough to allow for further modifications of the molecule which can be followed at a later stage by demethylation. Demethylation of S-methylglucagon regenerates the original covalent structure and is accomplished by treatment with Cleland's reagents at a pH of 10.5. The regenerated hormone is indistinguishable from native glucagon by its amino acid composition and its ability to stimulate the adenylyl cyclase system. The entire methylation-demethylation reaction sequence has been carried out with yields that approach 75%. The technique is suitable for the isotopic enrichment of native glucagon and may well be applicable to selected other methionine-containing peptides.

Bilateral tube thoracostomy to preclude fatal tension pneumothorax in patients with acute respiratory insufficiency

Two patients with acute respiratory insufficiency requiring prolonged mechanical ventilation are described. Both patients developed fatal unilateral tension pneumothoracies after the respiratory insufficiency appeared to be improving. The pneumothorax in each patient appeared to be the result of high inspiratory pressures resulting from high tidal volumes and positive end expiratory pressure. Currently, we recommend bilateral chest tube thoracostomies for those patients with inspiratory pressures greater than 40 cm H2O as a prophylaxis against this fatal complication.