Recent trends in the management of breast cancer. 4. Diagnosis and management of local recurrence after breast-conservation surgery

Long-term follow-up of patients in the National Surgical Adjuvant Breast Project protocol B-06 indicated that postoperative radiotherapy is effective in reducing local recurrence rates to less than 10%. Although some recurrences represent persistence of residual disease, a second type--a local manifestation of disseminated disease--presents as an extensive process involving several quadrants of the breast and extending to adjacent skin and chest wall. The first type is amenable to salvage therapy by either lumpectomy or mastectomy, depending on the clinical situation; the second type represents surgically inoperable disease and requires systemic therapy.

Fear of recurrence, breast-conserving surgery, and the trade-off hypothesis

Fear of recurrence has been at the heart of the controversy between surgeons favoring mastectomy versus those advocating a less radical operation. Breast-conserving surgery is thought to result in a better body image, but patients are expected to worry more about a cancer recurrence because only a small part of the breast is excised. To assess survival rates after breast-conserving intervention, patients were randomized into the National Surgical Adjuvant Breast Project (NSABP) prospective clinical trial (Protocol B06) with three treatment groups: total mastectomy, lumpectomy, and lumpectomy followed by radiation therapy. A fourth group was created to include patients who had a recurrence after their first operation and thus underwent a subsequent total mastectomy. Differences appeared, not according to the type of treatment, but with respect to the number of surgical interventions. Patients with multiple operations reported a greater fear of cancer recurrence and a worse body image, similar to those that underwent total mastectomy. Contrary to the trade-off hypothesis, patients who underwent radical surgery did not manifest less fear of recurrence. These results show unequivocally that the expected trade-off between breast conservation and fear of cancer recurrence does not occur. Those who undergo lumpectomy do not more express more fear of cancer than do patients who undergo mastectomy.

Strategies in the treatment of AIDS and related diseases: the lessons of cancer chemotherapy

The replication cycle of human immunodeficiency virus type 1 (HIV-1) consists of four distinct stages, each of which can be targeted for specific antiviral chemotherapy. The stages are (1) the attachment of virus to the CD4 receptor at the cell surface; (2) the uncoating of viral nucleic acid and its conversion via viral reverse transcriptase activity to DNA; (3) cellular multiplication, accompanied by the replication of integrated proviral DNA and production of viral RNA and proteins; and (4) the assembly and liberation of progeny virus from the cell and the potential reinitiation of the replication cycle in previously uninfected cells. Since each of these steps represents a potential target for anti-HIV chemotherapy, it is apparent that the rationale for the use of antiviral drugs is not dissimilar from the manner in which antineoplastic agents are targeted to specific stages in the replication cycle of tumor cells. As in the case of anticancer chemotherapy, it is hoped that combinations of drugs, which act against different steps in the viral replication cycle, might have synergistic potential. AZT or zidovudine is the most widely used drug to date to impede the replication of HIV-1; it is significant that this compound was designed initially with anticancer chemotherapy in mind. Although AZT therapy has been reasonably successful, this drug has had important toxic side effects. As in the case of many cancer chemotherapeutic agents, drug resistance to AZT is likely to be an important problem, and there have been several reports of the isolation of drug-resistant variants of HIV-1.

The relationship of chemotherapeutic and endocrine intervention on natural killer cell activity in human breast cancer

Peripheral blood natural killer (NK) activity against K562 target tumor cells was monitored in patients with breast cancer receiving no treatment, combination chemotherapy, and/or endocrine therapy. NK activity in untreated Stage I patients with no evidence of disease (ned) was significantly higher than in healthy controls. NK activity was shown to decline in individuals with cytotoxic drug therapy (P equals 0.036). There also were reduction in lymphocyte recoveries concomitant with chemotherapeutic intervention (P less than 0.001). Lymphocyte counts were incorporated in a calculation of absolute NK activity that more accurately reflected the significant reduction in NK activity that occurred in patients with localized and systemic disease on chemotherapy. Different chemotherapeutic agents were found to selectively affect NK activity. Stage II patients on phenylalanine mustard (P)/5-fluorouracil (F) (PF) and cyclophosphamide (C)/methotrexate (M)/5-fluorouracil (F) (CMF) protocols showed significant reductions in overall NK activity relative to healthy controls and Stage I patients with ned. Patients on P/doxorubicin (A)/F/tamoxifen (Tx) (PAFT) protocols showed reduced NK activity relative to Stage I patients. Patients on the short-dose C/A (CA) protocol showed normal levels of overall NK activity. High-risk Stage I patients on methotrexate (M)/F (MF)with sequential leucovorin rescue and patients with metastatic disease on endocrine therapy, i.e., Tx or megestrol acetate (Meg) showed overall NK activities in the range of healthy controls. Patients with systemic disease on CMF, CMF/vincristine/prednisone (CMFVP), vinblastine/A/thiotepa/fluoxymesterone (VATH), mitomycin/mitoxantrone (MtMx), and A regimens showed overall levels of absolute NK that were significantly less than either healthy controls or metastatic patients undergoing endocrine therapy. NK cytolytic data, monitored at multiple effector to target ratios, were subjected to exponential regression analysis. The elevation of NK cell responses in Stage I patients with ned and the decline of NK cell responses with cytotoxic chemotherapy were due to alterations in the maximal plateau levels of NK cell cytotoxicity represented by the A (asymptote) values. The k values obtained on regression analysis and indices of the relative killing capacities of individual NK cells remained unaltered in all populations. These results suggest that the cytolytic lymphocyte NK pool, elevated in Stage I patients with cancer, selectively declines as a result of cytotoxic therapy.

Two months of doxorubicin-cyclophosphamide with and without interval reinduction therapy compared with 6 months of cyclophosphamide, methotrexate, and fluorouracil in positive-node breast cancer patients with tamoxifen-nonresponsive tumors: results from the National Surgical Adjuvant Breast and Bowel Project B-15

The National Surgical Adjuvant Breast and Bowel Project (NSABP) implemented protocol B-15 to compare 2 months of Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH) and cyclophosphamide (AC) with 6 months of conventional cyclophosphamide, methotrexate, and fluorouracil (CMF) in patients with breast cancer nonresponsive to tamoxifen (TAM, T). A second aim was to determine whether AC followed in 6 months by intravenous (IV) CMF was more effective than AC without reinduction therapy. Through 3 years of follow-up, findings from 2,194 patients indicate no significant difference in disease-free survival (DFS, P = .5), distant disease-free survival (DDFS, P = .5) or survival (S, P = .8) among the three groups. Since the outcome from AC and CMF was almost identical, the issue arises concerning which regimen is more appropriate for the treatment of breast cancer patients. AC seems preferable since, following total mastectomy, AC was completed on day 63 versus day 154 for conventional CMF; patients visited health professionals three times as often for conventional CMF as for AC; women on AC received therapy on each of 4 days versus on each of 84 days for conventional CMF; and nausea-control medication was given for about 84 days to conventional CMF patients versus for about 12 days to patients on AC. The difference in the amount of alopecia between the two treatment groups was less than anticipated. While alopecia was almost universally observed following AC therapy, 71% of the CMF patients also had hair loss and, in 41%, the loss was greater than 50%. This study and NSABP B-16, which evaluates the worth of AC therapy in TAM-responsive patients, indicate the merit of 2 months of AC therapy for all positive-node breast cancer patients.

Postoperative chemotherapy and tamoxifen compared with tamoxifen alone in the treatment of positive-node breast cancer patients aged 50 years and older with tumors responsive to tamoxifen: results from the National Surgical Adjuvant Breast and Bowel Project B-16

The National Surgical Adjuvant Breast and Bowel Project (NSABP) conducted a randomized clinical trial to determine whether tamoxifen (TAM) plus chemotherapy is more effective than TAM alone in improving disease-free survival (DFS), distant disease-free survival (DDFS), and survival (S) of positive-node, TAM-responsive patients aged greater than or equal to 50 years. Women were randomized among three treatment groups: (1) TAM alone, (2) Adriamycin (doxorubicin; Adria Laboratories, Columbus, OH), cyclophosphamide, and TAM (ACT), or (3) melphalan (L-PAM), fluorouracil (5-FU), and TAM (PFT). The PFT arm was later modified so that new patients also received Adriamycin (PAFT). Findings from 1,124 eligible patients through 3 years of follow-up indicated a significantly better DFS for ACT-treated patients than for those receiving TAM alone (84% v 67%; P = .0004). An advantage in DDFS and S was also observed after ACT therapy (83% v 73% [P = .04 in the former] and 93% v 85% [P = .04 in the latter]). Both the DFS and DDFS of PAFT-treated patients were better than in those treated by TAM alone (83% v 66%, P = .0002 and 85% v 73%, P = .003). PFT patients also fared better in DFS and DDFS than TAM patients (81% v 72%, P = .07 and 85% v 74%, P = .02). Odds ratios consistently favored the three TAM-plus-chemotherapy groups. No significant S advantage is as yet evident in favor of the PAFT or PFT groups. Of importance is the failure of these studies to demonstrate an unfavorable interaction between the drug regimens used and the TAM, which was administered simultaneously. The findings related to the use of PAFT and PFT are of more biologic than clinical significance since L-PAM is rarely used in the treatment of breast cancer. The major conclusion from this study is the observance of a better outcome in positive-node breast cancer patients aged greater than or equal to 50 years from the use of postoperative prolonged TAM and short-course AC therapy (completed in 63 days) than from prolonged TAM therapy alone.

Natural killer cell function in patients with acquired immunodeficiency syndrome and related diseases

This review describes current knowledge of changes in natural killer (NK) cell function in acquired immunodeficiency syndrome (AIDS)-related disorders, vis-à-vis associated abnormalities in NK cytolytic function, NK cell subset distribution, NK cytopathology, and lymphokine regulation. NK cells, which are closely associated with large granular lymphocytes, are spontaneously cytotoxic to tumor and virally infected targets. As such, they may play a role in natural resistance to human immunodeficiency virus type 1 (HIV-1)-associated disorders and other opportunistic infections. Yet, peripheral blood NK activity is frequently reduced in patients with HIV-1-induced disease. NK cells are heterogeneous both with respect to their expression of serologically defined membrane antigens and functional activity. In AIDS-related syndromes, there appears to be a diminution of the NK pool (CD16+ cells) involved in cytolytic function, while there is an elevation of the NK pool that coexpresses NK (Leu 7+) and T (CD8+) cell markers, which show little or no involvement in cytolytic function. The impairment of in vitro NK function is not associated with a reduced frequency of lytic conjugates of effectors and target cells nor with the recycling capacity of these effector cells but rather is associated with defects in the NK cell lytic machinery following formation of such conjugates. NK cells in AIDS patients show an impairment in effector cell microtubule rearrangement following target cell interaction. The causes of NK cell dysfunction in AIDS-related disorders remain unknown. NK cells do not appear to express the CD4 epitope of the HIV receptor, nor have they been demonstrated to be susceptible to infection by HIV-1. There appears to be a preponderance of immature NK cells and a lymphokine imbalance in patients with HIV-1 associated disease. Interleukin-2 can partially restore diminished in vitro NK function. Elucidation of the involvement of the NK compartment in natural resistance to HIV-1 merits further investigation.

Tamoxifen as an alternative to surgical resection for selected geriatric patients with primary breast cancer

Thirty elderly patients with primary operable breast cancer were treated initially, because of refusal of surgery or because of infirmity, only with the antiestrogen tamoxifen citrate. Nineteen patients had regression of the primary tumor (complete in five and partial in 14). Eight patients were stable with no change, and three had measurable increases in the size of their primary tumors. Nine of the 30 eventually required locoregional treatment with surgery or radiotherapy for progression or recrudescence of their tumors after initial regression. No patient developed uncontrollable locoregional disease. For selected geriatric patients, treatment with tamoxifen alone permits a delay of surgery, which for some exceeds life expectancy.

Cytolysis of mammary tumor targets by resting, interleukin-2 stimulated and in vitro cultured peripheral blood lymphocytes from breast cancer patients

The cytotoxic capacity of resting, interleukin-2 (IL-2)-stimulated and in vitro cultured (3-5 days in 10 U/ml IL-2 containing media) peripheral blood lymphocytes (PBLs) from breast cancer patients to a panel of established mammary tumor cell lines was ascertained. Significant cytolysis (ranging from 7.8 to 12.4%, at an effector: target ratio of 20:1) of all mammary tumor targets (MCF-7, 734B, ZR-75-1, ZR-75-30, BT-20 and Hs578T) by PBLs was demonstrable in 18 h chromium release assays. Natural killer (NK) cytotoxicity was distinct from IL-2 stimulated (5 U/ml) and in vitro cultured PBL cytotoxicity in that resting PBLs were not cytolytic to RAJI cells, normal breast epithelia (Hs578Bst) and fibroblasts. Basal NK activity against mammary tumor targets was significantly reduced in patients receiving chemotherapy when compared to both untreated patients and normal controls. In criss-cross cold target inhibition studies, ZR-75-1 and K562 targets were not mutually competitive in NK cell assays (using resting PBLs) but were mutually competitive in lymphokine-activated killer (LAK) assays (using in vitro cultured PBLs). In eleven independent experiments, basal NK activity of ZR-75-1 cells was increased by a cold target excess of K562 (8.2 +/- 2.4% vs 30.5 +/- 5.2%, mean +/- SE, p greater than 0.01, cold:hot target ratio = 10:1). Interestingly, no such parallel increase of cytolysis of 734B targets by K562 cells was observed. Basal cytotoxicity against ZR-75-1 and K562 targets was serologically depleted using antibodies to natural killer cells HNK-1 and Leu 11b. Thus mammary tumor cell lines parallel autologous tumor cells, yet show features that are distinct from NK-resistant and sensitive lymphoid cell lines in their susceptibility to natural resistant cytolytic mechanisms.

Presence of somatomedin receptors on primary human breast and colon carcinomas

Competitive binding techniques were used to study the interaction of insulin-like growth factor I (IGF-I) with a plasma membrane-enriched subcellular fraction purified from primary breast and colon carcinoma specimens obtained at surgery. The presence of specific binding sites for IGF-I was detected in all tumour specimens studied. Scatchard analysis and competition studies with insulin and insulin-like growth factor-II (IGF-II) revealed the presence of specific IGF-I receptors, showing a Kd-value of approximately 2 nM. These results are consistent with the hypothesis that somatomedins play a role in determining the proliferative behaviour of human breast and colon tumors, and suggest that recent laboratory studies showing dependence of neoplastic cells on somatomedins for optimum proliferation may have clinical relevance.

Physician response to informed consent regulations for randomized clinical trials

To improve our understanding of physician reluctance to participate in randomized clinical trials, we examined physician responses to the regulation of obtaining written informed consent. Between June 1984 and February 1985 a purposive sample of 170 breast cancer specialists from eight countries completed a self-administered questionnaire and follow-up interview. The sample included 90 medical oncologists, 65 surgeons, and 29 radiotherapists. Responses to individual questions are presented in three global categories: (1) physician role--physicians believed that their view of their professional "self" was not compatible with informed consent regulations; (2) physician autonomy--physicians perceived a loss of individual decision-making power and an increase in professional accountability; and (3) physician-patient relationship--physicians stated that informed consent regulations influenced what they told trial patients and affected the ensuing doctor-patient relationship. Respondents developed complex methods to accommodate the incongruities they perceived between their view of their professional self and the need to obtain informed consent.

Depression and body image following mastectomy and lumpectomy

A twenty year debate about the appropriate surgery for breast cancer has resulted in two clinical trials comparing radical vs more conservative operations. Despite the favorable results of these trials, the majority of breast cancer patients in North America still undergo mastectomy. We investigated the psychological and social adjustment following total and partial mastectomy in a group of patients randomly assigned to one or the other operation (National Surgical Adjuvant Breast Protocol--B-06). Total mastectomy patients showed higher levels of depression and less satisfaction with body image. Partial mastectomy patients did not display any measurable increase in fear of recurrence. Patients undergoing radiation therapy showed surprising increase in depressive symptoms. Radiation therapy could well be more frightening to breast surgery patients than had been anticipated. These patients may benefit from some anticipatory counselling.

Peripheral blood natural killer cell activity in human breast cancer patients and its modulation by T-cell growth factor and autologous plasma

The role of clinical status and chemotherapeutic intervention on native and inducible natural killer cell (NK) activity in breast cancer was ascertained by determining the K562 cytotoxicity capacity of peripheral blood lymphocytes. The level of NK activity in breast cancer patients receiving chemotherapy (n = 62) was significantly lower than that observed in patients currently receiving no treatment (n = 56) (at effector: target [E:T] ratios of 20:1, 10:1, and 5:1, 23.8%, 17.9%, and 12.1% versus 34.9%, 25.6%, and 15.9%, respectively; P less than 0.01, two-way analysis of variance). The absolute level of NK activity in peripheral blood of cancer patients on therapy was further reduced when compared with untreated patients and healthy controls when reductions in lymphocyte counts concomitant with chemotherapeutic intervention were included in calculations of NK activity. T-cell growth factor (TCGF) increased NK activity in all breast cancer patients and healthy controls with maximal stimulation of basal activity at a concentration of 10% (volume/volume [v/v]) TCGF. The percent stimulation of basal NK activity by TCGF was significantly greater in patients receiving chemotherapy (26.4%, 24.3%, and 19.0% at an E:T of 20:1, 10:1, and 5:1, respectively; n = 23) than in untreated patients (16.6%, 18.5%, and 18.9%; n = 21) and healthy controls (23.5, 18.6, and 8.1; n = 8) (P less than 0.05 and P less than 0.01, respectively, two-way ANOVA). The influence of soluble factors and agents in serum on peripheral blood NK activity was assessed by monitoring the effects of autologous plasma on basal and TCGF-stimulated NK activity. Autologous plasma at concentrations less than or equal to 10% (v/v) enhanced basal NK activity. Levels of inducible NK activity in the presence of either 10% TCGF, 5% plasma, or a combination of both were not significantly different in statistical comparisons of both the effects of inducer and therapeutic modality. At concentrations of plasma greater than 10% (v/v), progressively decreasing NK activities were observed. T-cell growth factor could partially reverse the inhibitions of NK activity by 25% autologous plasma. In 13 experiments, basal NK activity and NK activity in the presence of 10% TCGF, 25% autologous plasma, and a combination of TCGF and plasma were 27.6%, 46.0%, 16.3%, and 28.1%, respectively (E:T = 20:1). This study indicates that NK function is compromised in breast cancer patients receiving cytotoxic drug-therapy. The potential use of TCGF in adjuvant immunotherapy as a modulator of NK function has been demonstrated.(ABSTRACT TRUNCATED AT 400 WORDS)

The relationship of clinical status and therapeutic modality to natural killer cell activity in human breast cancer

The role of clinical status and therapeutic intervention on natural cell-mediated cytotoxicity in breast cancer was ascertained by monitoring natural killer (NK) cell activity in peripheral blood samples. Patients with localized disease on chemotherapy showed significant reductions in NK activity concomitant with reduced lymphocyte numbers, when compared to untreated patients (18.1% versus 32.7%, P less than 0.005). Lymphocyte counts were included in a calculation of the absolute proportion of NK activity that incorporates a correction factor for the leukopenia that occurs as a result of cytotoxic therapy and disease progression. This calculation more accurately reflects the significant reduction of NK activity that occurs in patients with localized and systemic disease on chemotherapy when compared to untreated patients with no current evidence of disease (10.3% and 14.9% versus 30.7%, respectively; P less than 0.001). Different chemotherapeutic regimens were found to selectively affect NK cell function. The levels of both actual and absolute NK activity were significantly reduced in patients receiving 5-fluorouracil and L-phenylalanine mustard; cyclophosphamide, methotrexate, and 5-fluorouracil; and vincristine, Adriamycin (doxorubicin), and 5-fluorouracil, whereas only the levels of absolute NK activity were significantly reduced in patients receiving mitomycin, Megace (megestrol acetate), and Adriamycin when compared to untreated cancer patients. In contrast, tamoxifen-treated patients demonstrated levels of actual and absolute NK activity observed with untreated cancer patients. Patients receiving tamoxifen showed significantly elevated NK activity when compared to patients on all other chemotherapies. These results indicate that monitoring NK cell function may be useful in assessing the immunosuppressive effects of chemotherapeutic intervention.

Enhanced viral inhibition of lymphocyte mitogenesis in patients with advanced breast cancer

Virus particles are frequently able to non-specifically inhibit the capacity of human peripheral blood lymphocytes to respond to mitogenic or antigenic stimuli. In the case of breast cancer patients with advanced disease, the quantity of virus required to abrogate responsiveness to phytohaemagglutinin (PHA) was approximately four-fold less than that found when cells from healthy donors were employed. The results show that such virus co-incubated cultures are deficient with regard to their ability to synthesize detectable quantities of T cell growth factor (TCGF) activity, and that the extent of responsiveness to PHA in each case corresponds roughly to the amount of TCGF activity that is present in the cultures. While the addition of exogenous purified TCGF to cultures containing virus, normal cells and stimulus caused a reversal of the usual inhibitory effect, this finding was generally not obtained in the case of lymphocytes obtained from patients with advanced breast cancer. These data suggest that one mechanism of explaining diminished cellular immune responsiveness in breast cancer patients may be a relative inability of appropriate cells or subsets of cells to respond effectively to TCGF.

Reversible interference with TCGF activity by virus particles

Several types of virus particles including retroviruses and herpes viruses can impede the ability of human peripheral blood lymphocytes to respond to mitogenic stimuli. This is true even in the case of viruses that have been inactivated by u.v. light, indicating that the mechanisms involved are infection independent, at least in part. The observed inhibition could be shown to correlate with a reduced level of production of TCGF activity in the virus co-incubated cultures. In addition, these same viruses are apparently able to complex directly with TCGF activity and to render it biologically inactive. This was shown by allowing known quantities of virus to interact with TCGF activity for different periods of time, followed by centrifugation of any virus-TCGF complexes. This interference is reversible, however, and the dissociation of these virus-TCGF complexes by mild detergent, followed by viral centrifugation, yields TCGF activity in the supernatant.

Physicians' reasons for not entering eligible patients in a randomized clinical trial of surgery for breast cancer

We studied the reasons surgical principal investigators chose not to enter patients in a large, multicenter trial sponsored by a cooperative group. In 1976 the National Surgical Adjuvant Project for Breast and Bowel Cancers (NSABP) initiated a clinical trial to compare segmental mastectomy and postoperative radiation, or segmental mastectomy alone, with total mastectomy. Because the low rates of accrual were threatening to close the trial prematurely, we mailed a questionnaire to the 94 NSABP principal investigators, asking why they were not entering eligible patients in the trial. A response rate of 97 per cent was achieved. Physicians who did not enter all eligible patients offered the following explanations: (1) concern that the doctor-patient relationship would be affected by a randomized clinical trial (73 per cent), (2) difficulty with informed consent (38 per cent), (3) dislike of open discussions involving uncertainty (22 per cent), (4) perceived conflict between the roles of scientist and clinician (18 per cent), (5) practical difficulties in following procedures (9 per cent), and (6) feelings of personal responsibility if the treatments were found to be unequal (8 per cent). Further investigation into the behavioral aspects of the investigator-patient relationship is particularly pressing, since fear of change in this relationship was the most common reason given for not entering eligible patients in the trial.

Viral inhibition of lymphocyte mitogenesis: interference with the synthesis of functionally active T cell growth factor (TCGF) activity and reversal of inhibition by the addition of same

We have investigated the mechanisms whereby co-incubation of several types of virus particles with human lymphoid cells in the presence of T cell lectins leads to inhibition of the proliferative response that otherwise ensues. The data indicate that, in the absence of infection, such inhibition can be reversed by the addition to cultures of relatively high concentrations of fluids rich in T cell growth factor (TCGF) activity. The ability of these fluids to achieve such reversal of inhibition is both concentration- and time-dependent. Addition of the factor to virus co-incubated cells more than 26 hr after culture initiation does not restore responsiveness. We have also shown that virus co-incubated cultures are deficient with respect to their ability to synthesize detectable levels of TCGF activity in the presence of phytohemagglutinin. In contrast, the use of relatively dilute virus preparations (less than 10 particles per cell) permits partial responsiveness to lectin as well as the synthesis of moderate levels of TCGF. These finding suggest that viral inhibition of lymphocyte mitogenesis is mediated directly or indirectly by interference with the synthesis of functionally active TCGF activity.

Symposium on the diagnosis and treatment of common cancers. 2. Adjuvant therapy of breast cancer

Long-term survival of patients with breast cancer treated by operation alone has not improved despite many variations in local or regional treatment. Undetectable micrometastases present at the time of initial local treatment are the cause for later failures. Adjuvant systemic treatments have been introduced in the hope of reducing recurrence and mortality. In a series of protocols, the National Surgical Adjuvant Breast Project evaluated sequentially escalating drug therapies and noted a striking change in the natural history of the disease. Breast cancer is a heterogeneous group of diseases with different outcomes. Many of the therapies provide appreciably prolonged disease-free survival and ultimate survival for subsets of patients. Efforts should be made to recruit patients for further clinical trials in order to define better the most suitable treatments for the different subsets of patients.

Viral inhibition of lymphocyte mitogenesis: interference with the synthesis of functionally active T cell growth factor (TCGF) activity and reversal of inhibition by the addition of same

We have investigated the mechanisms whereby co-incubation of several types of virus particles with human lymphoid cells in the presence of T cell lectins leads to inhibition of the proliferative response that otherwise ensues. The data indicate that, in the absence of infection, such inhibition can be reversed by the addition to cultures of relatively high concentrations of fluids rich in T cell growth factor (TCGF) activity. The ability of these fluids to achieve such reversal of inhibition is both concentration- and time-dependent. Addition of the factor to virus co-incubated cells more than 26 hr after culture initiation does not restore responsiveness. We have also shown that virus co-incubated cultures are deficient with respect to their ability to synthesize detectable levels of TCGF activity in the presence of phytohemagglutinin. In contrast, the use of relatively dilute virus preparations (less than 10 particles per cell) permits partial responsiveness to lectin as well as the synthesis of moderate levels of TCGF. These finding suggest that viral inhibition of lymphocyte mitogenesis is mediated directly or indirectly by interference with the synthesis of functionally active TCGF activity.

Further studies on the mitogenic and immune-modulating effects of plasminogen activator

Plasminogen activator (PA), an enzyme which is secreted in large quantities by certain types of tumour cells, is an apparent lymphocyte mitogen. Treatment of mouse spleen cells with anti-Thy-1.2 serum plus complement prevents responsiveness, indicating that T cells are being stimulated to divide. In addition to the foregoing, we have shown that PA has the capacity to interfere with certain types of cell-mediated cytotoxicity and natural killer cell reactions in which tumour cells are employed as targets. These results suggest that PA may play an immune-modulating role which may be of importance in tumour self-defense.

The effects of T-cell growth factor and virus purification on virus-mediated inhibition of lymphocyte mitogenesis

Many different types of virus particles are able to non-specifically impede the ability of human peripheral blood lymphocytes to respond to mitogenic ro alloantigenic stimuli. This result is not obtained if ultra-purified virus is employed, although virus which has been banded only once through sucrose generally retains inhibitory potential. Ultra-pure virus is relatively unable to bind to cell surfaces, suggesting the importance of physical contact between viruses and cells in order for the observed inhibition to occur. Addition of exogenous T-cell growth factor (TCGF) to cultures containing virus, cells and stimulus causes a dose-dependent reversal of the usual inhibitory effect.

Adjuvant therapy for breast cancer

After several decades in which the scope and intensity of regional therapies increased, without a corresponding increase in cure rates, attention has turned to systemic treatments. Adjuvant therapy for carcinoma is use in an attempt to destroy micrometastases thus preventing the development of clinical metastases. Initial results have been encouraging and an understanding of tumor cell kinetics has led to the use of better schedules and combinations of drugs that have substantially decreased the probability or treatment failure and prolonged survival compared with the results of operation alone.

Cosmesis in segmental mastectomy

The controversy about the best treatment for primary breast cancer will be settled only when properly designed clinical trials are completed. Most surgeons would rather await the results of such trials than participate in them. Prominent among the reasons for this view is the belief that an adequate cancer operation can seldom be performed with appropriate cosmetic preservation of the breast and, therefore, the trial of an unproven operation is not justified, because nothing can be gained. The poor cosmetic result is often owing to lack of experience with segmental mastectomy. From experience with 400 patients in the National Surgical Adjuvant Breast Project (NSABP) protocol has emerged an appreciation of the technical points that permit adequately wide local excision with minimal cosmetic loss. The results should stimulate both patients and surgeons to consider appropriate clinical trials for primary breast cancer surgery. This paper considers the causes of cosmetic failure and suggests the means of overcoming them.

Non-specific inhibition by virus particles of human lymphocytes mitogenesis

Many different types of virus particles including avian retroviruses, Friend leukaemia virus and Sendai virus are able, when coincubated with human peripheral blood lymphocytes in the presence of mitogens or alloantigens, to inhibit the usual proliferative responses that normally ensue. These effects are independent of infection and can be obtained using u.v.-inactivated viruses as well as virus-lymphocyte combinations which are non-physiological in nature. Lymphocytes which are preincubated with viruses for as little as 5 min, and then washed free of unbound virus, are significantly impaired in terms of ability to react to mitogenic stimulus. These events may be mediated, in part at least, by the virus-induced elaboration by mononuclear cells of a factor with lymphocyte inhibitory potential.