Social and ethical implications of BRCA testing.

Oncologists are asked with increasing frequency to counsel their patients with respect to the medical, psychological and social repercussions of genetic testing for cancer susceptibility that may have been prescribed by physicians or carried out through direct-to-consumer tests. This article critically reviews the main ethical and social implications of BRCA testing, focusing on genetic responsibility and genetic discrimination. Genetic responsibility toward oneself and others is a highly debated implication of genetic testing for cancer predisposition that requires broad considerations of the boundaries between individual and community rights and a reappraisal of the notion of autonomy as relational. Physicians' duty to warn 'at risk' relatives can be an ethical quandary, yet confidentiality is key to the patient-doctor relationship. Mutation carriers may be subject to different forms and degrees of genetic discrimination and many individuals at risk have forgone BRCA testing to avoid potential discrimination. The scientific and medical community, together with patients and the public, has actively engaged against genetic discrimination. The legislation in many countries now protects against genetic discrimination by insurance companies and employers. Legal and regulatory issues are not the final answer to discrimination and profound cultural changes are required to create understanding and acceptance of all differences.

Clomiphene citrate effect on testosterone level and semen parameters in 18 infertile men with low testosterone level and normal/low gonadotropines level.

OBJECTIVE: To determine the effect of a 3-month course of clomiphene citrate (CC) on plasma testosterone (T) level and on semen parameters in 18 infertile men with low T level and normal or low gonadotropines level. STUDY DESIGN: A retrospective study was conducted by reviewing the medical records of men referred to a university fertility medicine unit for infertility management between January 2010 and March 2015. Men treated with CC for at least 3 months were included if they presented with: RESULTS: 18 patients met the inclusion criteria. CC was prescribed for 3 months at the dose of 50 mg every 48 h. Plasma T level was assessed at baseline and after 1 month of CC administration. Semen parameters were assessed at baseline and after 3 months of CC administration. The median pre-treatment T level was 9.1 nmol/l; after 1 month of CC treatment the median post-treatment T level increased to 20.2 nmol/l (p = <0.001). Median baseline sperm concentration was 7 millions/ml with a median progressive motility of 18%. After 3 months of CC, the median post-treatment sperm concentration was 17.5 millions/ml (p = 0.024) and the median post-treatment progressive sperm motility was 18% (p = 0.40). Three natural pregnancies occurred during the treatment period. CONCLUSION: CC is an effective and inexpensive treatment to increase plasma T level in infertile men with low T level and normal or low gonadotropines level. Our study suggests that CC could increase sperm concentration even in oligospermic infertile men, without, however, a significant effect on progressive sperm motility. More powered randomized controlled trials are needed to definitively assess CC effect on sperm parameters and on natural pregnancy rates.

Cultural aspects of communication in cancer care.

Cancer is increasing in incidence and prevalence worldwide, and the WHO has recently included cancer and its treatments as a health priority in developed and developing countries. The cultural diversity of oncology patients is bound to increase, and cultural sensitivity and competence are now required of all oncology professionals. A culturally competent cancer care leads to improved therapeutic outcome and it may decrease disparities in medical care. Cultural competence in medicine is a complex multilayered accomplishment, requiring knowledge, skills and attitudes whose acquisition is needed for effective cross-cultural negotiation in the clinical setting. Effective cultural competence is based on knowledge of the notion of culture; on awareness of possible biases and prejudices related to stereotyping, racism, classism, sexism; on nurturing appreciation for differences in health care values; and on fostering the attitudes of humility, empathy, curiosity, respect, sensitivity and awareness. Cultural competence in healthcare relates to individual professionals, but also to organizations and systems. A culturally competent healthcare system must consider in their separateness and yet in there reciprocal influences social, racial and cultural factors. By providing a framework of reference to interpret the external world and relate to it, culture affects patients' perceptions of disease, disability and suffering; degrees and expressions of concern about them; their responses to treatments and their relationship to individual physicians and to the healthcare system. Culture also influences the interpretation of ethical norms and principles, and especially of individual autonomy, which can be perceived either as synonymous with freedom or with isolation depending on the cultural context. This, in turn, determines the variability of truth-telling attitudes and practices worldwide as well as the different roles of family in the information and decision-making process of the cancer patient. Finally, culture affects individual views of the patient-doctor relationship in different contexts.

Pharmacology and clinical toxicity of 4'-iodo-4'-deoxydoxorubicin: an example of successful application of pharmacokinetics to dose escalation in phase I trials.

In a prospective phase I trial involving 35 patients with metastatic carcinoma, we tested a pharmacokinetic strategy for guiding dose escalation of the anthracycline 4'-iodo-4'-deoxydoxorubicin (I-DOX), a new analogue reported to be more potent and less toxic than doxorubicin. This strategy is potentially a safe and more rapid way of determining the maximum tolerated dose (MTD) of anticancer agents. Retrospective studies have shown that the total plasma drug exposure after a dose lethal to 10% of mice (LD10) is approximately equivalent to the total exposure produced in humans by the MTD. Thus, we intended to aim dose escalation in humans to achieve the area under the curve for I-DOX plasma concentration x time (AUC) equivalent to that produced in mice by an LD10. However, differences in I-DOX pharmacokinetics and metabolism in BDF1 mice and humans at the initial dose prevented immediate application of this strategy. Therefore, we escalated the dose by the modified Fibonacci scheme while investigating the pharmacology of I-DOX and its major plasma metabolite 4'-iodo-4'-deoxy-13-dihydrodoxorubicin (I-DOXOL). Plasma pharmacokinetics was characterized by rapid elimination and extensive metabolism of I-DOX to I-DOXOL. The ratio of I-DOXOL to I-DOX plasma AUC was 12.8 +/- 7.3 SD. The plasma pharmacokinetics of I-DOX and I-DOXOL were linear in the range of tested doses (2-90 mg/m2). The LD10 in mice was 6.8 mg/kg for I-DOXOL and 6 mg/kg for I-DOX, and the concentration of drug that inhibited by 50% (IC50) the growth of human granulocyte-macrophage colony-forming units (CFU-GM) was 80 nM for I-DOXOL and 50 nM for I-DOX. From these findings, we concluded that the toxic effects of I-DOX and I-DOXOL are equivalent and reset the pharmacokinetic target of escalation to the sum of I-DOX and I-DOXOL AUCs at I-DOX LD10. Then we safely applied pharmacokinetically guided escalation to determine the MTD (80 mg/m2). The plasma AUC of I-DOX and I-DOXOL at the human MTD is 71% of the AUC at mouse LD10. The only dose-limiting toxic effect was severe granulocytopenia.

Phase I and pharmacokinetic study of arabinofuranosyl-5-azacytosine (fazarabine, NSC 281272).

A Phase I clinical trial of 1-beta-D-arabinofuranosyl-5-azacytosine (ara-AC or fazarabine) given as a 72-h continuous infusion on a 21-day cycle was conducted in 27 adult patients with refractory cancer. The major toxicity was reversible granulocytopenia and thrombocytopenia. Dose-limiting toxicity was observed at a dose rate of 1.96 mg/m2/h in which Grade IV leukopenia (WBC less than 1,000/mm3) occurred in 4 of 11 patients and Grade IV thrombocytopenia (platelets less than 25,000/mm3) occurred in 3 of 11 patients. Plasma steady-state levels ranged from 0.13 to 0.6 microM for doses of 1.25 to 5.94 mg/m2/h. Mean total body clearance was 647 ml/min/m2. Minor clinical responses were seen in one patient with testicular cancer, one patient with colon cancer, one patient with breast cancer, and one patient with acute nonlymphocytic leukemia. Another patient with adenocarcinoma of unknown primary had stable disease during 13 cycles of therapy. Based on the results of this study, the recommended dose for Phase II studies of 1-beta-D-arabinofuranosyl-5-azacytosine administered as a 72-h continuous infusion is 2.0 mg/m2/h (48 mg/m2/day).

Paclitaxel and recombinant human granulocyte colony-stimulating factor as initial chemotherapy for metastatic breast cancer.

PURPOSE: A phase II study of Taxol (paclitaxel; Bristol-Myers Squibb Co, Princeton, NJ) as initial chemotherapy for metastatic breast cancer was conducted. Recombinant human granulocyte colony-stimulating factor (rhG-CSF) was used to ameliorate myelosuppression, the anticipated dose-limiting toxicity. PATIENTS AND METHODS: Twenty-eight patients with bidimensionally measurable breast cancer who had not received prior chemotherapy for metastatic disease were treated. Taxol was administered at 250 mg/m2 as a continuous 24-hour intravenous (i.v.) infusion every 21 days. rhG-CSF was administered at 5 micrograms/kg/d subcutaneously on days 3 through 10. RESULTS: Objective responses were observed in 16 of 26 assessable patients (62%; 95% confidence interval, 41% to 80%). There were three (12%) complete responses (CRs) and 13 (50%) partial responses (PRs). Ten of 16 patients (63%) who had received prior adjuvant chemotherapy responded, which included one CR and four PRs among eight patients who had received prior doxorubicin-containing therapy. Responses were observed in all sites of metastatic disease. The median time to first objective response was 5 weeks (range, 1 to 14). Administration of rhG-CSF was associated with a short duration of neutropenia (median, 2 days with absolute neutrophil count < 500 cells/microL). Eight of 26 patients (31%) who received more than one course received subsequent therapy without dose reduction. One hundred seventy-eight cycles of treatment were administered, with a median of six cycles per patient (range, one to 19). Eight courses (4.5%) were associated with admissions for neutropenic fever. Twenty-two patients (79%) did not require admission for neutropenic fever. Treatment was well tolerated. Adverse effects included generalized alopecia in all patients. Myalgias, arthralgias, and peripheral neuropathy were mild. No hypersensitivity reactions and no cardiac toxicity were observed. CONCLUSION: Taxol is highly active as initial chemotherapy for metastatic breast cancer. Administration of rhG-CSF reduced the incidence, depth, and duration of neutropenia, compared with published prior experience. Further studies of Taxol in breast cancer, including combinations with other active agents, are clearly warranted.

Residual abdominal masses in aggressive non-Hodgkin's lymphoma after combination chemotherapy: significance and management.

When patients with aggressive lymphoma present with intraabdominal disease, a stable residual mass is frequently detected radiographically at the time of the clinical complete remission. To discern the optimal management for this clinical problem, we reviewed 241 patients with aggressive lymphoma treated at the National Cancer Institute (NCI) from 1977 to 1986. Seventy-two/241 patients (30%) had an abdominal mass at diagnosis and 29/72 (40%) were left with a radiographically detectable residual mass at clinical complete remission. The likelihood of a residual mass was much higher for patients with bulky disease (P2 less than .0003) (two-tailed test [P2]). Twenty-nine patients had radiologically stable residual masses after therapy, and of 22 (76%) with pathologic evaluations, 21 had negative specimens (95%) and one was positive (5%). None of the patients with negative pathologic evaluation has relapsed in the abdominal site (median follow-up, 31 months). Seven patients were observed clinically without laparotomy: five are alive, without evidence of disease, at 2 to 9 years; two relapsed with disseminated disease within 2 months of chemotherapy. Initial tumor size and size of the residual mass did not correlate with residual disease, since residual masses identified by radiographic examination did not usually harbor viable lymphoma cells. Aspiration cytology was negative for residual tumor in 15/16 cases. One negative result was not confirmed at laparotomy, presumably due to sampling error. The one positive aspiration was followed by a negative laparotomy, possibly due to subsequent tumor necrosis. Restaging laparotomy has a low yield. In most patients with aggressive lymphoma who have otherwise completely responded to carefully administered full-dose combination chemotherapy, stable residual abdominal masses can be closely followed clinically without surgical exploration.

Sequential dose-dense doxorubicin, paclitaxel, and cyclophosphamide for resectable high-risk breast cancer: feasibility and efficacy.

PURPOSE: Dose-dense chemotherapy is predicted to be a superior treatment plan. Therefore, we studied dose-dense doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) as adjuvant therapy. METHODS: Patients with resected breast cancer involving four or more ipsilateral axillary lymph nodes were treated with nine cycles of chemotherapy, using 14-day intertreatment intervals. Doses were as follows: doxorubicin 90 mg/m2 x 3, then paclitaxel 250 mg/m2/24 hours x 3, and then cyclophosphamide 3.0 g/m2 x 3; all doses were given with subcutaneous injections of 5 microg/kg granulocyte colony-stimulating factor on days 3 through 10. Amenorrheic patients with hormone receptor-positive tumors received tamoxifen 20 mg/day for 5 years. Patients treated with breast conservation, those with 10 or more positive nodes, and those with tumors larger than 5 cm received radiotherapy. RESULTS: Between March 1993 and June 1994, we enrolled 42 patients. The median age was 46 years (range, 29 to 63 years), the median number of positive lymph nodes was eight (range, four to 25), and the median tumor size was 3.0 cm (range, 0 to 11.0 cm). The median intertreatment interval was 14 days (range, 13 to 36 days), and the median delivered dose-intensity exceeded 92% of the planned dose-intensity for all three drugs. Hospital admission was required for 29 patients (69%), and 28 patients (67%) required blood product transfusion. No treatment-related deaths or cardiac toxicities occurred. Doxorubicin was dose-reduced in four patients (10%) and paclitaxel was reduced in eight (20%). At a median follow-up from surgery of 48 months (range, 3 to 57 months), nine patients (19%) had relapsed, the actuarial disease-free survival rate was 78% (95% confidence interval, 66% to 92%), and four patients (10%) had died of metastatic disease. CONCLUSION: Dose-dense sequential adjuvant chemotherapy with doxorubicin, paclitaxel, and cyclophosphamide (A-->T-->C) is feasible and promising. Several ongoing phase III trials are evaluating this approach.

5-year results of dose-intensive sequential adjuvant chemotherapy for women with high-risk node-positive breast cancer: A phase II study.

PURPOSE: We conducted a phase II pilot study of dose-intensive adjuvant chemotherapy with doxorubicin followed sequentially by high-dose cyclophosphamide to determine the safety and feasibility of this dose-dense treatment and to estimate the disease-free and overall survival in breast cancer patients with four or more involved axillary lymph nodes. PATIENTS AND METHODS: Seventy-three patients received adjuvant treatment with four cycles of doxorubicin 75 mg/m(2) as an intravenous bolus every 21 days, followed by three cycles of cyclophosphamide 3,000 mg/m(2) every 14 days with granulocyte colony-stimulating factor support. RESULTS: Seventy-one patients were assessable, and all but two completed all planned chemotherapy. There was no treatment-related mortality. The most common toxicity was neutropenic fever, which occurred in 39% of patients. Median disease-free survival is 66 months (95% confidence interval, 34 to 98 months), and median overall survival has not yet been reached. At 5 years of follow-up, the disease-free survival is 51.7%, and overall survival is 60.0%. There is no long-term treatment-related toxicity, and no cases of acute myelogenous leukemia or myelodysplastic syndrome have been observed. CONCLUSION: Our pilot study of doxorubicin followed by cyclophosphamide demonstrates the safety and feasibility of the sequential dose-dense plan. Long-term follow-up, although noncomparative, is promising. However, this regimen is associated with a higher incidence of toxicity (and also higher costs) than the standard dose and schedule of doxorubicin and cyclophosphamide, and therefore it should not be used as conventional therapy in the absence of demonstrated improvement of outcome. Randomized trials testing the dose-dense approach have been completed but not yet reported. Because the sequential plan can decrease overlapping toxicities, it is an appropriate platform for the addition of newer active agents, such as taxanes or monoclonal antibodies.

Phase I study of escalating doses of edatrexate in combination with paclitaxel in patients with metastatic breast cancer.

Motivated by the observation of preclinical synergy, a Phase I dose escalation study of edatrexate in combination with a 3-h paclitaxel infusion was performed in patients with advanced breast cancer to determine the maximum tolerated dose (MTD) of edatrexate and the toxicities associated with this combination and to report preliminary observations of efficacy with this novel combination. Thirty-six patients were enrolled in this Phase I trial. Thirty-five eligible patients were treated every 21 days in cohorts of at least three patients and were assessable for toxicity. One patient was ineligible due to hyperbilirubinemia. Stepwise dose escalations of edatrexate were administered until grade >3 nonhematological dose-limiting toxicities were reported. The initial dose level of edatrexate was 180 mg/m2; subsequent cohorts were treated with escalating doses of edatrexate (210, 240, 270, 300, 350, and 400 mg/m2). Edatrexate was administered by i.v. infusion over 1 h. Paclitaxel was administered 24 h later at a fixed dose of 175 mg/m2 as a 3-h infusion with standard dexamethasone, diphenhydramine, and cimetidine premedication. The MTD of edatrexate was reached at the 350 mg/m2 level in this study. Grade 3 diarrhea was seen in one patient at the 300 and 400 mg/m2 dose levels, requiring dose reductions. Two patients experienced grade 4 stomatitis at the 400 mg/m2 dose level and also required dose reduction, establishing the MTD as 350 mg/m2. Grade 3 nausea and vomiting were noted in two of three patients at the highest dose level. Of 35 patients, 4 patients reported grade 3 myalgias and 1 patient reported grade 3 neurosensory complaints, which were seen mostly at the 350 and 400 mg/m2 dose levels; however, 1 patient reported grade 3 myalgias at 180 mg/m2. No cumulative neurotoxicity was observed, and no patient experienced an allergic reaction to paclitaxel. In 23 patients with bidimensionally measurable disease, there were four complete (17%) and seven partial responses, with an overall response rate of 48% (95% confidence interval, 27-69%). All of the responses were seen in patients who had not received prior chemotherapy for stage IV disease. The median duration of response was not assessable because many responding patients went on to receive high-dose chemotherapy treatment with stem cell support. The combination of edatrexate and paclitaxel for treatment of metastatic breast cancer is a feasible and safe regimen. The MTD of edatrexate was 350 mg/m2 when combined with a 3-h infusion of paclitaxel (175 mg/m2) given 24 h later. Activity was noted even among patients who had relapsed shortly after receiving methotrexate- and/or doxorubicin-containing adjuvant regimens. Additional studies evaluating the sequences and dosing schema for this combination are warranted to improve the response proportion and define the duration of the response.

Taxol plus recombinant human granulocyte-colony stimulating factor as initial and as salvage chemotherapy for metastatic breast cancer: a preliminary report.

Twenty-eight patients received Taxol as their first chemotherapy for stage IV breast cancer. An additional 51 patients with extensive prior exposure to other chemotherapeutic agents received Taxol as salvage therapy. We found significant activity for the drug in both situations, as well as a strong clinical suggestion of non-cross-resistance with doxorubicin. An excellent response in previously irradiated skin was noted in one case. The routine use of recombinant human granulocyte-colony stimulating factor seemed to ameliorate some of the dose-limiting toxicity of neutropenia. Other toxicity was mild to moderate in most cases. With further development, Taxol should play a significant role in the systemic management of breast cancer.

Ethical implications of genetic testing for breast cancer susceptibility.

The identification of gene mutations involved in hereditary breast cancer is a major recent scientific discovery, enabling us to identify women at very high risk, and also providing the means to understand the biology of breast cancer and to explore novel preventive strategies. Yet, it carries medical, psychological, ethical and social implications. This paper is a review of all the ethical implications of genetic testing for breast cancer predisposition, as well as an attempt to discuss the more philosophical questions of women facing BRCA testing. To what extent does the individual benefit from genetic knowledge? Some women look with trepidation upon the potential of planning their life in view of a risk, while others believe that only through knowledge and awareness we can improve control of our life. The risk of breast cancer may be qualitatively so important to justify all the potential risks of finding out about it.

Phase II study of semisynthetic paclitaxel in metastatic breast cancer.

The aim of this phase II study was to characterise the efficacy and toxicity of semisynthetic paclitaxel in patients with metastatic breast cancer. Eligible patients had measurable disease and had been treated with one prior chemotherapy regimen either as adjuvant or for metastatic disease. Semisynthetic paclitaxel was given at a dose of 175 mg/m2 over 3 h every 21 days with dexamethasone, cimetidine and diphenhydramine premedications. 31 patients were entered. All were evaluable for toxicity. 30 patients were evaluable for response because 1 patient was lost to follow-up after receiving one cycle. One patient achieved a complete response and 10 patients achieved partial responses for an overall response rate (CR + PR) of 37% (95% confidence interval 20-56%). 17 patients (55%) experienced at least one episode of grade 3 or 4 neutropenia. There were two episodes of febrile neutropenia complicating 155 cycles of therapy. One of these resulted in a treatment-related death in a patient with pulmonary metastasis. 3 patients required dose reductions for grade 3 sensory neuropathy. Our study shows that the antitumour activity and toxic effects of semisynthetic paclitaxel appear to be identical to the naturally occurring product.

Sequential adjuvant therapy: the Memorial Sloan-Kettering Cancer Center experience.

Adjuvant chemotherapy has a real but modest impact on the disease-free and overall survival of patients with breast cancer. Recent attempts to improve its effectiveness have focused on dose intensity and new agents. Sequential therapy maximized dose intensity while limiting overlapping toxicity. Sequential therapy using doxorubicin followed by cyclophosphamide/methotrexate/5-fluorouracil (CMF) has been found superior in patients with high-risk resectable breast cancer. The novel chemotherapy agent paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) is now known to be highly active in advanced breast cancer and appears to be clinically non-cross-resistant with doxorubicin. Therefore, this drug is being studied as a component of the next generation of adjuvant chemotherapy regimens. The most appropriate way to incorporate paclitaxel has not yet been defined, but its concurrent administration with other agents has, in some cases, been troublesome. Based on the demonstrated advantage of the sequential plan for doxorubicin and CMF, we conducted a series of pilot trials testing sequential high-dose therapy. Initially, we studied multiple cycles of doxorubicin followed by cyclophosphamide; we later added paclitaxel to this regimen. These phase II studies demonstrate the feasibility of sequential therapy with doxorubicin, paclitaxel, and cyclophosphamide, and early disease-free survival results are promising. Cooperative group projects are under way or planned to further define the activity of these regimens.

Preliminary experience with paclitaxel (Taxol) plus recombinant human granulocyte colony-stimulating factor in the treatment of breast cancer.

Single-agent paclitaxel (TAXOL) was administered to 79 patients with stage IV breast cancer. Twenty-eight patients had no prior chemotherapy (for metastatic disease), and 51 patients had extensive exposure to other chemotherapeutic agents before beginning the 24-hour paclitaxel infusion. Routine use of recombinant human granulocyte colony-stimulating factor helped to ameliorate neutropenia, the dose-limiting toxicity, in some cases. Other toxicity was generally mild to moderate. Paclitaxel was more active in patients whose stage IV disease had not yet been exposed to chemotherapy, but activity was seen in the patients previously treated extensively as well. There is a strong clinical suggestion of non-cross-resistance with doxorubicin. In one case, an excellent response in previously irradiated skin was seen. Paclitaxel is a very promising agent for the treatment of metastatic breast cancer.

Autotransplants in advanced non-Hodgkin lymphoma: are they effective?

Recent data suggest that intensive therapy followed by a bone marrow autotransplant is effective in advanced intermediate and high-grade non-Hodgkin lymphoma (predominantly large-cell lymphoma). Twelve studies of autotransplants were analyzed to determine outcome. Results compared to data from 29 chemotherapy studies. Complete remission was reported in 53% of autotransplant recipients versus 17% of persons receiving chemotherapy. Two-year disease-free survival was 16 and 2%, respectively. It is uncertain whether these differences indicate superiority of autotransplants or reflect selection biases. Also unknown is whether similar results might not be obtained with similarly intensive treatment without an autotransplant.

[Kinetics of breast neoplasms]. / Le basi cinetiche delle neoplasie mammarie.

Breast cancer is a disease moderately responsive to chemotherapy. While its curability is inversely related to the tumor burden, a relevant number of patients still progress to metastatic disease even after adjuvant chemotherapy. Also, high-dose chemotherapy appears promising, but can not yet be considered ultimately curative of breast cancer. Different variables, biological, kinetic and treatment-related, account for the clinical behaviour of this disease. In order to improve its curability, they will all need to be taken into account in planning future treatment strategies. One of the most effective ways to understand and predict the clinical behaviour of breast cancer is the development of appropriate mathematical models explaining its growth-patterns. Aim of this paper is to review the two fundamental models, the exponential and the Gompertzian. The exponential model is at the basis of the Skipper-Schabel and the Goldie-Coldman hypotheses, while the Norton-Simon hypothesis has been formulated from the gompertzian model. The latter appears to better fit the vast amount of clinical data which are presently available: from Bloom's analysis of untreated breast cancer patients, to the results of large clinical trials, to the data emerged from the recent meta-analysis. Characteristic of a gompertzian growth pattern is that exponential growth is matched by exponential retardation of growth. In 1943 Delbruck and Luria demonstrated that random mutations could account for the development of virus resistance in bacteria and were able to estimate the rate of mutation as a function of the growth rate of bacteria. Shortly after Law demonstrated that resistance to methotrexate in murine leukemia occurred similarly. The concept of combination chemotherapy actually derived from the idea that cancer cells could be resistant to chemotherapy even before exposure to it. Goldie and Coldman applied the Delbruck/Luria model to hypothesize the use of non cross-resistant alternating combination chemotherapy as a better way to eliminate the risk of resistance. They also suggested that many different drugs were to be used as soon as possible, when the tumor size is still small. Most of their predictions were based on the Skipper/Schabel model of the exponential growth of cancer and on its deriving log-kill model. A large amount of clinical data are now suggesting that the behaviour of breast cancer is best described by gompertzian growth: in particular, gompertzian growth is a tenable model of breast cancer growth for both the unperturbed and the perturbed (by treatment) states.(ABSTRACT TRUNCATED AT 400 WORDS)

[Autotransplantation in lymphomas: is it effective?]. / Autotransplantatsiia pri limfomakh: iavliaetsia li ona éffektivnoi.

Recent data suggest that intensive chemotherapy, with or without radiation, followed by a bone marrow autotransplant is effective in advanced intermediate and high-grade non-Hodgkin lymphoma (predominantly large-cell lymphoma). We analyzed 12 studies of the autotransplants to determine outcomes. The results were compared to data from 29 chemotherapy studies. Complete remissions were reported in 53 percent of autotransplant recipients versus 17 percent of persons receiving chemotherapy. Two-year disease-free survival was 16 percent and 3 percent, respectively. It is uncertain whether these differences reflect subject selection or time to treatment (time censoring) biases in the autotransplant cohort. A randomized trial is needed to determine if autotransplants are superior to chemotherapy. Also unknown is whether similar results might not be obtained with higher doses of chemotherapy without an autotransplant.