Similar breast cancer cell contamination of single-day peripheral-blood progenitor-cell collections obtained after priming with hematopoietic growth factor alone or after cyclophosphamide followed by growth factor

PURPOSE

To evaluate tumor-cell contamination of peripheral-blood progenitor-cell (PBPC) collections obtained after priming with granulocyte colony-stimulating factor (G-CSF).

PATIENTS AND METHODS

Immunocytochemical (ICC) and tumor clonogenic (TCA) assays were used to analyze tumor-cell contamination of pretreatment peripheral-blood (PB) and bone marrow (BM) samples, and of PBPC collection samples obtained after priming with G-CSF 5 micrograms/kg/d for 5 or 7 days in 38 women with advanced breast cancer undergoing high-dose chemotherapy (HDC). Results were compared with 37 historical control patients who underwent PBPC mobilization with cyclophosphamide (4 g/m2) followed by granulocyte-macrophage colony-stimulating factor (GM-CSF) 5 micrograms/kg/d for 14 days.

RESULTS

Before PBPC priming with G-CSF, only one of 37 (3%) PB and four of 36 (11%) BM samples had tumor cells detected by ICC. Tumor-cell contamination of PBPC collections obtained after 5 or 7 days of G-CSF priming was observed in only three of 38 patients (8%). All patients with tumor cells detected in the PBPC collection had stage IV disease. Cells with in vitro clonogenic potential were detected only in the pretreatment BM sample in one patient, and another two patients had ICC- and TCA-positive PBPC samples despite tumor-negative PB and BM before priming. These results are similar to those previously reported for PBPC primed with cyclophosphamide and GM-CSF.

CONCLUSION

In patients with advanced breast cancer responsive to cytotoxic chemotherapy, tumor-cell contamination is not increased in PBPC collected after 5 or 7 days priming with G-CSF and appears similar to that seen when PBPC are primed with cyclophosphamide followed by GM-CSF.

Impact of age on outcome of patients with cancer undergoing autologous bone marrow transplant

PURPOSE

We examined the impact of age on outcomes in patients with cancer undergoing autologous bone marrow transplantation (ABMT).

PATIENTS AND METHODS

All 506 adult patients who underwent ABMT at the Johns Hopkins Oncology Center between January 1987 and January 1994 were studied. A total of 405 patients were aged 18 to 49 years and 101 were aged > or = 50. The effect of age and other prognostic variables on transplant-related mortality (TRM), relapse, and event-free survival rates were analyzed.

RESULTS

Patients aged > or = 50 years has a 2.24-fold increased risk of TRM. Although relapse rates were not different based on age, the increased TRM rate resulted in a slight decrease in overall event-free survival in the older patients. Causes of death were not different by age and were mainly related to preparative regimen toxicity. Length of hospital stay and hospitalization costs were not increased in the older patients.

CONCLUSION

While the TRM rate was higher in older patients, relapse rates were not increased. Nearly 25% of older patients were expected to be cured of the disease. These data support the use of ABMT in eligible older patients, at least up to the age of 65.

Erythroderma after autologous bone marrow transplantation modified by administration of cyclosporine and interferon gamma for breast cancer

BACKGROUND

Allogeneic graft-versus-host disease is associated with decreased rates of tumor relapse. The addition of interferon gamma to cyclosporine, given to induce graft-versus-host disease after autologous bone marrow transplantation, increases the extent of the cutaneous eruption.

OBJECTIVE

Our purpose was to describe the clinical and histologic cutaneous changes in 10 patients with breast cancer who received interferon gamma to potentiate graft-versus-host disease after autologous bone marrow transplantation modified by cyclosporine.

METHODS

Ten women receiving autologous bone marrow transplantation modified by the administration of cyclosporine and interferon gamma were observed clinically with sequential biopsy of the skin weekly and at the time of cutaneous eruptions.

RESULTS

Erythroderma (stage 3) developed in five women after the first or second administration of interferon gamma. At least on skin biopsy specimen from 7 of the 10 women showed grade 2 changes of graft-versus-host reaction, including all patients with erythroderma. Epidermal intercellular edema was prominent in these specimens with expression of keratinocyte HLA-DR and intercellular adhesion molecule 1. Induction of keratinocyte HLA-DR and intercellular adhesion molecule 1 expression was not observed in specimens from normal skin during administration of interferon gamma.

CONCLUSION

This protocol causes a more widely distributed cutaneous eruption, including erythroderma (50%), than autologous bone marrow transplantation and cyclosporine administration alone (3%). Whether it will affect survival is unknown.

Motility and chemotaxis in Serpulina hyodysenteriae

Chemotactic- or motility-regulated mucus association appears to be the predominant mechanism of mucosal association by the causative agent of swine dysentery, Serpulina hyodysenteriae. In the present study, a modification of the Adler capillary assay was used to evaluate the chemotactic responses of S. hyodysenteriae to a variety of potential stimuli. First, however, it became necessary to study factors that influenced motility of the spirochete in vitro, since standard cultivation methods produced motility inferior to that observed for in vivo grown cells. A number of factors were found to influence S. hyodysenteriae motility, but of these growth medium and growth phase appeared to be the most important. The type and even batch of culture medium also were found to have a significant influence on S. hyodysenteriae motility. Optimal motility and chemotaxis for S. hyodysenteriae was observed when the cells were harvested in mid- to late-log phase, and in vivo-like motility could be induced by suspending the cells in physiologic saline. S. hyodysenteriae was strongly attracted to hog gastric mucin, certain concentrations of blood, L-fucose, L-serine and other compounds. Selected sugars and other amino acids did not serve as chemoattractants for S. hyodysenteriae. The chemotactic response of S. hyodysenteriae toward L-fucose and L-serine, constituents of mucin, may be important factors in the affinity of the spirochete for the mucus in the intestinal tract of swine.

Phase I and pharmacologic study of sequences of paclitaxel and cyclophosphamide supported by granulocyte colony-stimulating factor in women with previously treated metastatic breast cancer

PURPOSE

Pacltaxel is active in metastatic breast cancer, but limited information is available on combinations of this agent with other cytotoxic agents. Study aims were to determine the maximum-tolerated doses (MTDs) of paclitaxel (24-hour infusion) and cyclophosphamide (1-hour infusion) administered every 21 days with granulocyte colony-stimulating factor (G-CSF, filgrastim) to determine the effect of drug sequence on toxicity and pharmacology and to evaluate the activity of this combination in women with anthracycline-resistant disease.

PATIENTS AND METHODS

Thirty-seven women with metastatic breast cancer were treated. Starting doses were paclitaxel 135 mg/m2 and cyclophosphamide 750 mg/m2, with filgrastim 5 microG/kg/d subcutaneously beginning 24 hours after chemotherapy. Four patients were treated at each dose level. The sequence of drug administration was alternated between sequential patients, and with subsequent courses of therapy in each patient, to enable evaluation of effects of drug sequence on toxicity and pharmacology. Patients were treated every 21 days and disease status was reevaluated every two courses.

RESULTS

Paclitaxel 200 mg/m2 and cyclophosphamide 1,250 mg/m2 is the MTD for this combination on this schedule. The hematopoietic toxicity of therapy was sequence-dependent. Paired analysis of toxicity data indicated more severe toxicity in courses in which paclitaxel was administered first. Sequence-dependent pharmacologic effects did not account for this phenomenon. Responses were noted in 29% of patients with anthracycline-resistant disease.

CONCLUSION

Paclitaxel 200 mg/m2 and cyclophosphamide 1,250 mg/m2 with filgrastim administered every 21 days are the doses recommended for further study.

The world's first brewery exclusively designed to use continuous fermentation: biotechnology history made in New Zealand

When New Zealand Breweries Ltd's Standard Brewery opened in Palmerston North, New Zealand on October 9, 1958 it was the first brewery in the world built exclusively to brew beer using continuous fermentation. The use of continuous fermentation in New Zealand sparked a revolution in the way beer was brewed around the world. This is the story of the people and the brewery that made continuous beer fermentation a reality.

Inactivation of Serpulina hyodysenteriae flaA1 and flaB1 periplasmic flagellar genes by electroporation-mediated allelic exchange

Serpulina hyodysenteriae, the etiologic agent of swine dysentery, contains complex periplasmic flagella which are composed of multiple class A and class B polypeptides. To examine the role these proteins play in flagellar synthesis, structure, and function and to develop strains which may provide insight into the importance of motility in the etiology of this pathogen, we constructed specific periplasmic flagellar mutations in S. hyodysenteriae B204. The cloned flaA1 and flaB1 genes were disrupted by replacement of internal fragments with chloramphenicol and/or kanamycin gene cassettes. Following delivery of these suicide plasmids into S. hyodysenteriae, homologous recombination and allelic exchange at the targeted chromosomal flaA1 and flaB1 genes was verified by PCR, sequence, and Southern analysis. The utility of a chloramphenicol resistance gene cassette for targeted gene disruption was demonstrated and found more amenable than kanamycin as a selective marker in S. hyodysenteriae. Immunoblots of cell lysates of the flagellar mutants with antiserum raised against purified FlaA or FlaB confirmed the absence of the corresponding sheath or core protein. Both mutations selectively abolished expression of the targeted gene without affecting synthesis of the other flagellar polypeptide. flaA1 and flaB1 mutant strains exhibited altered motility in vitro and were less efficient in movement through a liquid medium. Paradoxically, isogenic strains containing specifically disrupted flaA1 or flaB1 alleles were capable of assembling periplasmic flagella that were morphologically normal as evidenced by electron microscopy. This is the first report of specific inactivation of a motility-associated gene in spirochetes.

Detection of tumor cells in the bone marrow, peripheral blood, and apheresis products of breast cancer patients using flow cytometry

One of the possible drawbacks to autologous bone marrow (BM) and peripheral blood progenitor cell (PBPC) transplantation in breast cancer patients is the potential for tumor cell contamination in the transplanted product. To assess the presence of breast cancer cells, we have developed a flow-cytometric method using cytokeratin-FITC and CD45-phycoerythrin (PE) to detect very low levels of cytokeratin-positive (CK+) tumor cells in mononuclear cell (MNC) preparations. In a model system using PBMNC and the breast cancer cell line CAMA, the sensitivity of detection of this flow-cytometric method was one tumor cell in 200,000 MNC. This method was used to evaluate BM, PB, and apheresis products (AP) from 44 patients with metastatic breast cancer. When possible, stained cytologic examination was performed on smears of the unprocessed specimens and on flow cytometry-sorted cells. Results indicated that CK+ tumor cells could be detected by flow cytometry in all three specimen types. When present, however, the tumor content (per MNC) tended to be higher in BM than in PB or AP. Samples from a given patient taken serially over the course of chemotherapy revealed variable results, suggesting that the presence of tumor contamination may be sporadic and requires evaluation of each stem cell product. Of 75 samples tested with both flow cytometry and cytology, the results were concordant in 54 cases (72%). In the remaining samples, flow cytometry only was positive in 15 cases (20%), and cytology only was positive in six cases (8%). This flow-cytometric technique is useful in the evaluation of transplant products for CK+ tumor cell contamination.

Treatment of metastatic breast cancer with combination paclitaxel/cyclophosphamide

Paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) has demonstrated substantial single-agent activity against both minimally pretreated and resistant metastatic breast cancer. Evaluation of paclitaxel-based combinations has demonstrated appreciable activity, but also toxicity, for the paclitaxel/doxorubicin combination. The paclitaxel/cyclophosphamide combination is potentially attractive because of the significant single-agent activity of both drugs against metastatic breast cancer and the paucity of shared nonhematologic toxicities. This combination is being evaluated in women with doxorubicin-refractory metastatic breast cancer. Dose escalation to paclitaxel 200 mg/m2 over 24 hours and cyclophosphamide 2,000 mg/m2 administered every 21 days with granulocyte colony-stimulating factor support has been performed. The final dose level was complicated by dose-limiting toxicity. The maximum tolerated dose for this combination is currently being defined. There is preliminary evidence of sequence-dependent toxicity. Grade 4 neutropenia and neutropenic fevers are more frequent in cycles in which paclitaxel is administered first.

Phase I and pharmacologic study of the alkylating agent modulator novobiocin in combination with high-dose chemotherapy for the treatment of metastatic breast cancer

PURPOSE

Resistance to alkylators may potentially be overcome by drugs that inhibits DNA repair, thus improving the efficacy of high-dose chemotherapy. This trial was performed to determine if novobiocin, an agent that inhibits DNA repair, could be given with high-dose alkylators. Study aims were to define the toxicities and maximal-tolerated dose (MTD) of novobiocin and the pharmacokinetics of novobiocin and high-dose cyclophosphamide and thiotepa.

PATIENTS AND METHODS

Thirty-eight women with responsive metastatic breast cancer received high-dose cyclophosphamide (3 to 6 g/m2 over 4 days), thiotepa (400 to 800 mg/m2), and novobiocin (0.5 to 5.0 g/d x 7, orally) with autologous marrow support. Toxicity was monitored. The pharmacology of novobiocin, cyclophosphamide, and thiotepa was evaluated.

RESULTS

There were no toxic deaths. The MTD of novobiocin was 4 g/d. All seven patients treated at 5 g/d developed grade III/IV mucositis and vomiting. The severity of mucositis correlated with the plasma levels of novobiocin. Other severe toxicities were not observed. Plasma novobiocin levels > or = 100 micrograms/mL, which are associated with reversal of drug resistance in animal models, were consistently seen at dose levels greater than 2 g. The dispositions of cyclophosphamide and thiotepa were not altered by novobiocin.

CONCLUSION

Novobiocin may be given with high-dose alkylators in doses that produce plasma levels that augment the activity of these cytotoxics in experimental models. The pharmacology of high-dose cyclophosphamide and thiotepa is unaffected. Novobiocin 4 g/d orally for 7 days is recommended for future study.

Nonlinear pharmacokinetics of cyclophosphamide in patients with metastatic breast cancer receiving high-dose chemotherapy followed by autologous bone marrow transplantation

The pharmacokinetics of cyclophosphamide has been evaluated in 15 patients with metastatic breast cancer undergoing high-dose chemotherapy with alkylating agents followed by autologous bone marrow transplantation. Each patient received two courses of chemotherapy: 4 g/m2 of cyclophosphamide by 90-min infusion prior to peripheral blood progenitor cell collection (the first course) and 6 g/m2 of cyclophosphamide with 800 mg/m2 of thiotepa by 96-h constant infusion before marrow and stem cell reinjection (the second course). In the first course, plasma cyclophosphamide concentration-time data of 9 of 15 patients were fit by a one-compartment model with Michaelis-Menten saturable elimination in parallel with first-order renal elimination. The mean (SD) Vmax and Km values were 1.47 (0.89) microM/min and 575 (347) microM, respectively. The first course data of the remaining six patients were fit using first-order elimination only. In the second drug course, plasma cyclophosphamide disposition curves of 13 of 15 patients demonstrated a decline in concentration following attainment of an initial steady state. The plasma cyclophosphamide disposition data of these patients were fit by a one-compartment pharmacokinetic model, in which the decline of plasma cyclophosphamide concentration after reaching the initial steady state was modeled as being due to an increase in the clearance rate of cyclophosphamide. The mean (SD) initial and final clearance rates were 51 (16) ml/min and 106 (48) ml/min, respectively. Michaelis-Menten elimination was not apparent in the second course because the plasma concentration of cyclophosphamide was much lower. The mean renal clearance rate was 17 ml/min in the first course and 16 ml/min in the second course. Urinary excretion of cyclophosphamide accounted for 17% and 23% of the total dose administered in the first and the second course, respectively. No change in cyclophosphamide clearance rate was apparent in a patient who was taking phenytoin, but a change was present in a patient who was taking phenobarbital. A drug interaction between cyclophosphamide and thiotepa may explain the smaller initial clearance rate for cyclophosphamide during the second drug course.

Absence of breast cancer cells in a single-day peripheral blood progenitor cell collection after priming with cyclophosphamide and granulocyte-macrophage colony-stimulating factor

The effect of priming on occult tumor cell involvement of peripheral blood (PB) and PB progenitor cell (PBPC) collections is poorly characterized. Using sensitive immunocytochemistry (ICC) and tumor clonogenic assays (TCA) specific for epithelial-derived tumor cells, hematopoietic specimens were analyzed for PBPC and occult tumor cell involvement in 28 patients with chemotherapy-sensitive stage IIIB or IV breast cancer. Before PBPC priming, tumor was detected by ICC in PB of 1 of 23 (4%) patients and in bone marrow (BM) harvests of 4 of 27 (15%) patients. Fifteen days after cyclophosphamide and granulocyte-macrophage colony-stimulating factor (GM-CSF) priming, 2 of 28 (7%) patients had ICC-positive PBPC collections. The median amplification of CD34+ PBPC during this time was over 19-fold (range, < 1 to 199). One patient had pretreatment tumor involvement of both PB and BM. One patient grew tumor colonies in TCA; the PB and BM were ICC- and TCA-positive, but the PBPC collection was ICC-positive and TCA-negative. After cytoreduction with conventional-dose chemotherapy, patients with advanced breast cancer and histologically negative BM biopsy specimens have rare tumor cell involvement of PB and BM. Despite effective PBPC priming with cyclophosphamide and GM-CSF, clonogenic breast cancer cells were not found in the PBPC collection performed on day 15.

Large-volume leukapheresis using regional citrate anticoagulation to collect peripheral blood progenitor cells

The use of peripheral blood progenitor cells (PBPC) for hematopoietic rescue after high-dose chemotherapy is limited by the number of leukaphereses required to collect an adequate number of hematopoietic progenitors. To optimize the collection of PBPC, we evaluated a single large-volume leukapheresis protocol with citrate anticoagulation. A group of 23 patients received cyclophosphamide (4 g/m2) and GM-CSF (5 micrograms/kg/day for 15 days) as PBPC mobilization, with a single outpatient 6 h leukapheresis performed on the COBE Spectra 15 days later. Citrate (0.190 mmol/ml) was infused at 1.2 ml/L of blood/minute with a whole blood to citrate ratio between 17:1 and 25:1. Calcium chloride (50 mM) was administered at a citrate to calcium molar ratio between 10:1 and 5:1 to prevent hypocalcemia. A median 36.6 L (range 24.4-46.4) blood was processed using 338 mM citrate (269-473) and 50 mM calcium (25-75). A median 5 x 10(6) CD34+ cells/kg (< 0.3-24) and 6.2 x 10(5) CFU-GM/kg (< 0.001-29) were collected, representing 5.6 and 5.9 more PBPC, respectively, than were in circulation at the initiation of leukapheresis. We conclude that a 6 h large-volume leukapheresis following cyclophosphamide and GM-CSF mobilization is safe, can recruit hematopoietic progenitors into the circulatory compartment, and allows the collection of high numbers of PBPC in a single procedure.

Vinorelbine and the topoisomerase 1 inhibitors: current and potential roles in breast cancer chemotherapy

Vinorelbine is a semi-synthetic vinca alkaloid which was initially developed in France in the 1980's. Due to its unique structure it is considerably less neurotoxic than vincristine. Several phase II studies have shown that vinorelbine is active in metastatic breast cancer therapy with response rates of 20-30% in pretreated and 40-50% in nonpretreated patients respectively. Higher response rates have been noted when vinorelbine is used in combination regimens. The main dose-limiting toxicity seen with this agent has been neutropenia; neurotoxicity manifest as symptomatic paresthesia can be seen in 10% of treated patients. Oral and implantable forms of the drug have also been investigated. The topoisomerase 1 inhibitors topotecan and camptothecin 11 (CPT-11) have been less extensively evaluated in breast cancer therapy. Preclinical studies have indicated that both of these agents are active against breast cancer and some responses have been seen in phase 1 trials of topotecan. An 8% response rate was noted in a phase II trial of CPT-11 in patients with pretreated metastatic breast cancer. Further phase II trials are ongoing at present with both agents.

Systemic adjuvant therapy for breast cancer

Systemic adjuvant therapy reduces the mortality due to breast cancer to a modest extent. Current research directions focus on both increasing the efficacy of therapy, predominantly by increasing the intensity of treatment, and attempting to reduce toxicity by treating only those patients at significant risk of relapse. Improved understanding of both the metastatic process and the mechanisms by which cytotoxic treatments exert their effects hold the promise for more effective treatments in the future. Cost-benefit analyses demonstrate the relative cost-effectiveness of adjuvant systemic therapies for patients at significant risk of recurrence, for whom the effectiveness of treatment is substantial.

The efficacy of ivermectin (pour-on) against the eyeworms, Thelazia gulosa and Thelazia skrjabini in naturally infected cattle

Sixteen crossbred beef cattle, 6-8 months of age, were used to determine the efficacy of ivermectin in a pour-on formulation against natural infections of Thelazia spp. Cattle were weighed on Day 0, ranked in descending order by bodyweight and sequentially paired. Within each pair, one animal was randomly assigned to an untreated control group, while the other animal was treated with a pour-on formulation of ivermectin applied topically at 1.0 ml per 10 kg bodyweight to achieve a dosage of 500 mg ivermectin kg-1 body weight. On Day 14 all animals in both treatment groups were slaughtered. The eyes and surrounding tissues were removed and examined for eyeworms. A total of 86 adult worms (74 Thelazia skrjabini and 12 Thelazia gulosa) were recovered from the untreated control animals. T. skrjabini was found in seven, and T. gulosa in three, of the eight untreated control animals. Two T. skrjabini, one from each of two animals, were found on the surface of the eyes of cattle that had received ivermectin treatment. The reduction in the geometric mean number for T. gulosa collected from treated animals was 100% (P > 0.1) relative to controls, and 97.02% (P = 0.0025) for T. skrjabini relative to controls.

Site segregation of Thelazia skrjabini and Thelazia gulosa (Nematoda: Thelazioidea) in the eyes of cattle

One thousand three hundred and twenty-two eyes obtained from slaughtered cattle throughout Alberta were examined for eyeworms. Each eye was partitioned into 9 sites and all eyeworms were recorded by site. Seven hundred eyeworms were recovered from 121 infected eyes. The distribution of Thelazia skrjabini across the 9 sites differed significantly (P < 0.001) from that of Thelazia gulosa. The 2 major lacrimal ducts associated with the Harderian gland contained 58% (354/613) of the T. skrjabini present, whereas the large ventral lateral duct of the orbital gland contained 58% (50/87) of the T. gulosa recovered. Eyeworms occurred more often (90%, 631/700) in a duct as a single species than as a mixed species infection (10%, 69/700). The data suggest that T. skrjabini and T. gulosa are more site specific than previously believed.

Bone marrow micrometastases in chemotherapy-responsive advanced breast cancer: effect of ex vivo purging with 4-hydroperoxycyclophosphamide

Tumor contamination of hematopoietic stem cell grafts may influence the outcome of breast cancer patients treated with high-dose chemotherapy. The goals of this study were: (a) to evaluate the prevalence of tumor contamination of bone marrow (BM) harvests in patients responding to systemic chemotherapy; (b) to evaluate reduction of BM tumor contamination by ex vivo purging with 4-hydroperoxycyclophosphamide (4HC); and (c) to compare the tumor contamination of peripheral blood progenitor cell collections and BM in advanced-stage breast cancer patients designated for peripheral blood progenitor cell infusion. We evaluated pre- and post-4HC purge BM specimens from 20 patients for tumor contamination using immunocytochemistry and for in vitro growth potential of tumor cells using a tumor cell clonogenic assay. Pre-4HC purge BM specimens from 15 of 20 (75%) patients were immunocytochemistry and tumor cell clonogenic assay negative. The remaining 5 BM specimens were immunocytochemistry positive, but only 3 of 5 specimens were tumor cell clonogenic assay positive. In vitro tumor colony growth was not observed in any post-4HC purge BM specimens. We also evaluated nine patients with bone or BM metastases from the start of induction chemotherapy. We found less tumor involvement of peripheral blood progenitor cell collections than of simultaneously obtained bone marrow aspirates. We conclude that bone marrow micrometastases occur with low frequency in women with chemotherapy-sensitive breast cancer and that ex vivo purging with 4HC may render tumor cells nonviable.

Breast cancer marker Ca549. A multicenter study

A multicenter study of CA549, a marker for breast cancer, was conducted using sera from 1721 patients with benign and malignant conditions by an immunoradiometric assay, BRESMARQ. Acceptable assay performance was demonstrated by studies of intra-assay (2.2% to 12% coefficient of variation [CV]), interassay (4.1% to 11.8% CV), and interlaboratory (4.8% to 8.7% CV) precision; sensitivity (.3 kU/L); linearity; recovery; high-dose hook effect (up to 10,000 kU/L); and interferences (human antimouse antibodies; protein, bilirubin, hemoglobin levels; lipid and cancer therapeutic agents). A reference interval of 0-12.5 kU/L (women) and 0-11.9 kU/L (men) was established from 746 healthy persons. The distribution of values exceeding the reference range for benign conditions was as follows: pregnant and lactating women (2%); benign breast disease (5%); and seven other benign diseases, including liver (24%), lung (19%), prostate (14%), colon, endometrial, gastric, and ovarian (< 10%). For nonbreast cancers, the distribution was Hodgkin's (7%), colon (10%), endometrial (15%), gastric (15%), lymphoma (15%), prostate (20%), ovarian (39%), and liver (45%). For breast cancer, the distribution was stage I (5%), stage II (14%), stage III (32%), and stage IV (74%). The receiver-operating characteristic analysis demonstrated the usefulness of CA549 as a marker in stage IV breast cancer.