Survival patterns of invasive lobular and invasive ductal breast cancer in a large population-based cohort with two decades of follow up.

BACKGROUND: Invasive lobular carcinoma (ILC) comprises 8-15 % of all invasive breast cancers and large population-based studies with >10 years of follow-up are rare. Whether ILC has a long-time prognosis different from that of invasive ductal carcinoma, (IDC) remains controversial. PURPOSE: To investigate the excess mortality rate ratio (EMRR) of patients with ILC and IDC and to correlate survival with clinical parameters in a large population-based cohort. MATERIAL AND METHODS: From 1989 through 2006, we identified 17,481 patients diagnosed with IDC (n = 14,583) or ILC (n = 2898), younger than 76 years from two Swedish Regional Cancer Registries. Relative survival (RS) during 20 years of follow up was analysed. RESULTS: ILC was significantly associated with older age, larger tumours, ER positivity and well differentiated tumours. We noticed an improved survival for patients with ILC during the first five years, excess mortality rate ratio (EMRR) 0.64 (CI 95 % 0.53-0.77). This was shifted to a significant decreased survival 10-15 years after diagnosis (EMRR 1.49, CI 95 % 1.16-1.93). After 20 years the relative survival rates were similar, 0.72 for ILC and 0.73 for IDC. CONCLUSIONS: During the first five years after surgery, the EMRR was lower for patients with ILC as compared to patients with IDC, but during the years 10-15 after surgery, we observed an increased EMRR for patients with ILC as compared to IDC. These EMRR between ILC and IDC were statistically significant but the absolute difference in excess mortality between the two groups was small.

Prognostic role of serum thymidine kinase 1 kinetics during neoadjuvant chemotherapy for early breast cancer.

BACKGROUND: Emerging data support the use of thymidine kinase 1 (TK1) activity as a prognostic marker and for monitoring of response in breast cancer (BC). The long-term prognostic value of TK1 kinetics during neoadjuvant chemotherapy is unclear, which this study aimed to elucidate. METHODS: Material from patients enrolled to the single-arm prospective PROMIX trial of neoadjuvant epirubicin, docetaxel and bevacizumab for early BC was used. Ki67 in baseline biopsies was assessed both centrally and by automated digital imaging analysis. TK1 activity was measured from blood samples obtained at baseline and following two cycles of chemotherapy. The associations of TK1 and its kinetics as well as Ki67 with event-free survival and overall survival (OS) were evaluated using multivariable Cox regression models. RESULTS: Central Ki67 counting had excellent correlation with the results of digital image analysis (r = 0.814), but not with the diagnostic samples (r = 0.234), while it was independently prognostic for worse OS [adjusted hazard ratio (HRadj) = 2.72, 95% confidence interval (CI) 1.19-6.21, P = 0.02]. Greater increase in TK1 activity after two cycles of chemotherapy resulted in improved event-free survival (HRadj = 0.50, 95% CI 0.26-0.97, P = 0.04) and OS (HRadj = 0.46, 95% CI 0.95, P = 0.04). There was significant interaction between the prognostic value of TK1 kinetics and Ki67 (pinteraction 0.04). CONCLUSION: Serial measurement of serum TK1 activity during neoadjuvant chemotherapy provides long-term prognostic information in BC patients. The ease of obtaining serial samples for TK1 assessment motivates further evaluation in larger studies.

Gonadotrophin stimulation and risk of relapse in breast cancer.

STUDY QUESTION: Is gonadotrophin stimulation as part of IVF associated with an increased risk of relapse in breast cancer? SUMMARY ANSWER: Controlled ovarian stimulation (COS) in connection with IVF in women with previous breast cancer was not associated with an increased risk of breast cancer relapse. WHAT IS KNOWN ALREADY: Breast cancer is the most common malignancy among women worldwide and the leading cause of cancer death among females. The use of COS with gonadotrophins with subsequent cryopreservation of oocytes or embryos in order to enhance the chances of pregnancy after cancer treatment is the current most established fertility preservation method for women with breast cancer. To date, there are only a few small retrospective hospital-based controlled studies evaluating the risk of breast cancer relapse in patients undergoing fertility preservation with or without COS, showing no evident risk of relapse in breast cancer after the use of gonadotoxic agents. STUDY DESIGN SIZE DURATION: This was a retrospective, population-based cohort study comprising 5857 women with previous breast cancer of whom 337 were exposed to COS. Exposure (COS) and outcomes (relapse and death) were identified for all patients from 2005 to 2014 by assessing the National Quality Register for Assisted Reproduction, the Swedish Medical Birth Register, the National Patient Register, the Swedish Prescribed Drug Register, the Swedish Cause of Death Register, the National Breast Cancer Register and the Swedish Cancer Register. Matching according to set criteria was possible for 334 women, who constituted the control group. A total of 274 women had undergone IVF after completing breast cancer treatment and 63 women had undergone COS for fertility preservation at the time of breast cancer diagnosis. PARTICIPANTS/MATERIALS SETTING METHODS: Women aged 20-44 years previously diagnosed with breast cancer and exposed to COS were matched for age at breast cancer diagnosis ±5 years, tumour size and lymph node involvement with a non-exposed control group, including women with known T- and N-stages. In a subsequent analysis, the matched cohort was assessed by also including women with unknown T- and N-stages. A secondary analysis comprised the entire non-matched cohort, including all women with known T- and N-stages. Also here, a subsequent analysis included women with missing data for T- and N-stages. The risk of relapse in breast cancer was estimated as crude hazard ratios (HRs) and 95% CI using Cox proportional hazards models in the primary and secondary analyses where T- and N-stages were known: otherwise the risks of relapse were only given descriptively. MAIN RESULTS AND THE ROLE OF CHANCE: In the primary matched analysis, relapse occurred in 20 of 126 women exposed to COS (15.9%) compared with 39 of 126 (31.0%) in the control cohort (HR = 0.70; 95% CI 0.39-1.45; P = 0.22). In the subsequent analysis, also including women with unknown T- and N-stages, relapse occurred in 27 of 337 (8.0%) women having undergone COS compared with 71/334 (21.3%) among the non-exposed. In the secondary adjusted analysis, relapse occurred in 20 of 126 (15.9%) exposed women and in 918 of 3729 (24.6%) non-exposed women (HR = 0.81; 95% CI 0.49-1.33; P = 0.70). In the subsequent analysis, including unknown T- and N-stages, relapse occurred in 27 of 337 (8.0%) women in the exposed group and 1176 of 5520 (21.3%) in the non-exposed cohort. LIMITATIONS REASONS FOR CAUTION: A substantial degree of missing data on important prognostic variables was a limitation, particularly when analysing the total cohort. Furthermore, data on confounding factors, such as BMI, were not completely covered. Another limitation was that a pre-specified variable for relapse was not in use for the majority of the National Breast Cancer Register. Furthermore, the follow-up time from available register data (2005-2014) is rather short. Finally, we cannot be sure whether the prognostic information from receptor status, showing a lower incidence in the exposed group, is representative. Information on T- and N-stages was missing in more than half of the patients. WIDER IMPLICATIONS OF THE FINDINGS: In this large, retrospective, matched cohort study, we found no increased risk of relapse in breast cancer among women who had been exposed to gonadotrophins as part of IVF. This is reassuring but might be confounded by the selection of a group of women with a more favourable prognosis than those not undergoing IVF. The present study strengthens previous findings by being large, national and register based. Its results are applicable to women undergoing fertility preservation as well as to those undergoing regular IVF treatment. STUDY FUNDING/COMPETING INTERESTS: Supported in part by grants from the Swedish state under the agreement between the Swedish government and the county councils the ALF-agreement (ALFGBG-720291), The Assar Gabrielsson Fund (FB 15-20), The Breast Cancer Fund and the Swedish Association of Local authorities and Regions, SKR. There are no conflicts of interest to declare. TRIAL REGISTRATION: N/A.

No increased risk of relapse of breast cancer for women who give birth after assisted conception.

STUDY QUESTION: Is childbirth after IVF associated with a risk of relapse in breast cancer? SUMMARY ANSWER: Women who had been diagnosed with breast cancer and completed treatment had no increased risk of relapse if they gave birth after conceiving with IVF. WHAT IS KNOWN ALREADY: Pregnancy and childbirth have not been shown to increase the risk of relapse in breast cancer. Ovarian stimulation during IVF increases the oestrogen levels and could theoretically increase the risk of relapse in breast cancer. STUDY DESIGN SIZE DURATION: This is a retrospective register study, using national Swedish register data from the National Patient Register, the Medical Birth Register, the Swedish National Cancer Register, the National Breast Cancer Register, the National Quality Registry of Assisted Reproduction (Q-IVF), the National IVF Dataset, the Swedish Prescribed Drug Register and the Cause of Death Register. All women diagnosed with breast cancer who were between 20 and 44 years of age during the years 1982 to 2014 and identified in the cancer registries were assessed. PARTICIPANTS/MATERIALS SETTING METHODS: Women, previously diagnosed with breast cancer, who had given birth after IVF (29 after completed breast cancer treatment and 8 after fertility preservation) were compared with a matched control group who had given birth after spontaneous conception. Matching was done in a ratio 1:4, based on T-stage (size of the tumour) and year of diagnosis +/-5 years. MAIN RESULTS AND THE ROLE OF CHANCE: We found 26 114 women that had been diagnosed with breast cancer when 20-44 years old and of those 860 had subsequently given birth, 823 after spontaneous and 37 after IVF conception. Follow-up time was similar between the groups, ranging from 2.6 to 24.0 years, with a mean follow-up time of 10.3 (SD 4.2) years in the IVF group and 10.7 (SD 4.4) years in the control group. There were no relapses (0/37) in the IVF group. The relapse rate for the matched controls was 36/148 (24.8%). Ten women who suffered relapse died due to breast cancer. LIMITATIONS REASONS FOR CAUTION: This is reassuring data; however, the result is based on a few cases. The poor coverage of important prognostic variables in the register resulted in uncertain comparability of the groups. The main limitation in this study is the extent of missing data on tumour-related variables, due to poor coverage from the early years of the National Breast Cancer Register. It is possible that the women accepted for IVF had a less aggressive breast cancer and were generally healthier than women delivering after conceiving spontaneously and therefore had a lower risk of relapse. Other limitations are the lack of information on the anticancer therapies used and type of disease relapse, plus the older of the two IVF registers did not hold information on unsuccessful IVF cycles, leaving only cycles leading to birth, to be analysed. WIDER IMPLICATIONS OF THE FINDINGS: We found no indication that women who had been diagnosed with breast cancer had an increased risk of relapse if they gave birth after conceiving with IVF. Based on our findings, there is no evidence to advise against IVF treatment in this group of women. More detailed registry data would be valuable for future studies, enabling proper matching of tumour characteristics between groups. STUDY FUNDING/COMPETING INTERESTS: The study was financed by grants from the Swedish state under the agreement between the Swedish government and the county councils, the ALF-agreement (ALFGBG-720291), The Assar Gabrielsson Fund (FB 15-20), The Breast Cancer Fund and the Swedish Association of Local Authorities and Regions, SKL. There are no conflicts of interest to declare.

No clear effect of postoperative radiotherapy on survival of breast cancer patients with one to three positive nodes: a population-based study.

BACKGROUND: In published radiotherapy trials, the failure rate in the control arm among patients with one to three positive nodes is high compared with that seen with modern adjuvant treatments. Therefore, the generalizability of the results has been questioned. The aim of the present study was to compare relative survival in breast cancer patients between two Swedish regions with screening mammography programs and adjuvant treatment guidelines similar with the exception of the indication of radiotherapy for patients with one to three positive nodes. PATIENTS AND METHODS: Between 1989 and 2006, breast cancer patients were managed very similarly in the west and southeast regions, except for indication for postoperative radiotherapy. In patients with one to three positive nodes, postmastectomy radiotherapy was generally given in the southeast region (89% of all cases) and generally not given in the west region (15% of all cases). For patients with one to three positive nodes who underwent breast-conserving surgery, patients in the west region had breast radiotherapy only, while patients in the southeast region had both breast and lymph nodes irradiated. RESULTS: The 10-year relative survival for patients with one to three positive lymph nodes was 78% in the west region and 77% in the southeast region (P = 0.12). Separate analyses depending on type of surgery, as well as number of examined nodes, also revealed similar relative survival. CONCLUSION: Locoregional postoperative radiotherapy has well-known side-effects, but in this population-based study, there was little or no influence of this type of radiotherapy on survival when one to three lymph nodes were involved.

Molecular subtype and tumor characteristics of breast cancer metastases as assessed by gene expression significantly influence patient post-relapse survival.

BACKGROUND: We and others have recently shown that tumor characteristics are altered throughout tumor progression. These findings emphasize the need for re-examination of tumor characteristics at relapse and have led to recommendations from ESMO and the Swedish Breast Cancer group. Here, we aim to determine whether tumor characteristics and molecular subtypes in breast cancer metastases confer clinically relevant prognostic information for patients. PATIENTS AND METHODS: The translational aspect of the Swedish multicenter randomized trial called TEX included 111 patients with at least one biopsy from a morphologically confirmed locoregional or distant breast cancer metastasis diagnosed from December 2002 until June 2007. All patients had detailed clinical information, complete follow-up, and metastasis gene expression information (Affymetrix array GPL10379). We assessed the previously published gene expression modules describing biological processes [proliferation, apoptosis, human epidermal receptor 2 (HER2) and estrogen (ER) signaling, tumor invasion, immune response, and angiogenesis] and pathways (Ras, MAPK, PTEN, AKT-MTOR, PI3KCA, IGF1, Src, Myc, E2F3, and ß-catenin) and the intrinsic subtypes (PAM50). Furthermore, by contrasting genes expressed in the metastases in relation to survival, we derived a poor metastasis survival signature. RESULTS: A significant reduction in post-relapse breast cancer-specific survival was associated with low-ER receptor signaling and apoptosis gene module scores, and high AKT-MTOR, Ras, and ß-catenin module scores. Similarly, intrinsic subtyping of the metastases provided statistically significant post-relapse survival information with the worst survival outcome in the basal-like [hazard ratio (HR) 3.7; 95% confidence interval (CI) 1.3-10.9] and HER2-enriched (HR 4.4; 95% CI 1.5-12.8) subtypes compared with the luminal A subtype. Overall, 25% of the metastases were basal-like, 32% HER2-enriched, 10% luminal A, 28% luminal B, and 5% normal-like. CONCLUSIONS: We show that tumor characteristics and molecular subtypes of breast cancer metastases significantly influence post-relapse patient survival, emphasizing that molecular investigations at relapse provide prognostic and clinically relevant information. CLINICALTRIALS.GOV: This is the translational part of the Swedish multicenter and randomized trial TEX, clinicaltrials.gov identifier nct01433614 (http://www.clinicaltrials.gov/ct2/show/nct01433614).

Prognostic information of a previously diagnosed sister is an independent prognosticator for a newly diagnosed sister with breast cancer.

BACKGROUND: Breast cancer survival has been shown to be associated among relatives. In this study, we used a population-based cohort of Swedish sisters, both diagnosed with breast cancer, to determine whether prognostic information of a previously diagnosed sibling is useful for the clinical management of a newly diagnosed sibling. PATIENTS AND METHODS: The population-based cohort included all sister pairs, 1617 sisters, diagnosed with breast cancer in Sweden, from 1 January 1992, through 31 December 2006, with complete follow-up. All information was collected manually from original pathology reports and patient records. The Kappa statistic was used to measure the agreement of primary tumor characteristics between the sisters. We modeled the breast cancer-specific survival using multivariate (Cox) proportional hazard analyses in two steps categorizing the older sister's survival. RESULTS: Estrogen receptor status was the only tumor characteristic significantly associated between the sisters [κ 0.18 (95% confidence interval (CI) 0.089-0.27)]. Younger sisters with poor older sister survival showed significantly worse survival compared with patients with good older sister survival (log rank, P = 0.017). A twofold increased hazard ratio (HR) for death from breast cancer was found in younger sisters with poor older sister survival compared with patients with good sister survival [HR 2.56 (95% CI 1.16-5.65)], adjusting for age and calendar period of diagnosis, socioeconomic factors, number of children and hospital of primary tumor diagnosis. When further adjusting for primary tumor characteristics and adjuvant therapy, the risk for death from breast cancer in younger sisters with poor older sister survival became more pronounced [HR 3.35 (1.34-8.34)]. CONCLUSIONS: Our findings derived from a population-based cohort of Swedish sister pairs suggest that breast cancer-specific survival is inherited independent of tumor characteristics and treatment in the sibling later diagnosed with the disease. Prognostic information of a previously diagnosed sibling with breast cancer could be important in the clinical management.

Angiogenic factors in relation to clinical effect in a phase II trial of weekly paclitaxel.

BACKGROUND: Several anticancer agents including paclitaxel have an inhibitory effect on angiogenesis. AIMS: To compare the overall response rate and time to progression with changes in circulating angiogenic factors during palliative treatment with weekly paclitaxel. MATERIAL AND METHODS: Patients with metastatic BC, ECOG 0-2, received weekly paclitaxel, concomitant with trastuzumab if HER2+ BC (n = 7). Circulating vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) were determined at base-line and before start of new course. RESULTS: Fifty-five of 63 included patients were evaluable. The overall response rate including stable disease ≥24 weeks (CR + PD + SD) was obtained in 25 of the evaluable patients (45%). The median time to progression (TTP) was 5.3 months and overall survival (OS) 16.7 months. Patients with triple negative breast cancer (TNBC) showed a trend towards higher base-line VEGF compared with hormone receptor positive or HER2+ tumours and had shorter TTP. Significant differences in VEGF and bFGF levels at 12 weeks were found between patients with longer versus shorter TTP (VEGF: p = 0.046, bFGF: p = 0.005) and between patients gaining versus lacking clinical benefit (VEGF: p = 0.05, bFGF: p = 0.02). CONCLUSIONS: The clinical utility of circulating VEGF may be a useful tool for monitoring treatment efficacy.

Serum thymidine kinase activity compared with CA 15-3 in locally advanced and metastatic breast cancer within a randomized trial.

The primary objective was to estimate serum thymidine kinase 1 (TK1) activity, reflecting total body cell proliferation rate including cancer cell proliferation, in women with loco regional inoperable or metastatic breast cancer participating in a prospective and randomized study. Secondary objectives were to analyze TK1 in relation to progression-free survival (PFS), overall survival (OS), therapy response and other tumour characteristics, including CA 15-3, widely used as a standard serum marker for disease progression. TK1 and CA 15-3 were analysed in 198 serum samples collected prospectively from women included in the randomized TEX trial between December 2002 and June 2007. TK1 activity was determined by the ELISA based DiviTum™ assay, and CA 15-3 analyses was generated with the electrochemiluminescence immunoassay Cobas Elecsys CA 15-3 II. High pre-treatment TK1 activity predicted shorter PFS (10 vs. 15 months p = 0.02) and OS (21 vs. 38 months, p < 0.0001), respectively. After adjustment for age, metastatic site and study treatment TK1 showed a trend as predictor of PFS (p = 0.059) and was an independent prognostic factor for OS, (HR 1.81, 95 % confidence interval (CI) 1.26-2.61, p = 0.001). There was a trend of shortened OS for women with high CA 15-3 (p = 0.054) in univariate analysis, but not after adjustment for the above mentioned covariates. Both TK1 (p = 0.0011) and CA 15-3 (p = 0.0004) predicted response to treatment. There were statistically different distributions of TK1 and CA 15-3 in relation to the site of metastases. TK1 activity measured by DiviTum™ predicted therapy response, PFS and OS in loco regional inoperable or disseminated breast cancer. These results suggest that this factor is a useful serum marker. In the present material, a prognostic value of CA 15-3 could not be proven.

Individually tailored treatment with epirubicin and paclitaxel with or without capecitabine as first-line chemotherapy in metastatic breast cancer: a randomized multicenter trial.

Anthracyclines and taxanes are active cytotoxic drugs in the treatment of early metastatic breast cancer. It is yet unclear whether addition of capecitabine to the combination of these drugs improves the treatment outcome. Patients with advanced breast cancer were randomized to first-line chemotherapy with a combination of epirubicin (Farmorubicin(®)) and paclitaxel (Taxol(®)) alone (ET) or in combination with capecitabine (Xeloda(®), TEX). Starting doses for ET were epirubicin 75 mg/m(2) plus paclitaxel 175 mg/m(2), and for TEX epirubicin 75 mg/m(2), paclitaxel 155 mg/m(2), and capecitabine 825 mg/m(2) BID for 14 days. Subsequently, doses were tailored related to side effects. Primary endpoint was progression-free survival (PFS); secondary endpoints were overall survival (OS), time to treatment failure (TTF), objective response (OR), safety and quality of life (QoL). 287 patients were randomized, 143 to ET and 144 to TEX. Median PFS was 10.8 months for patients treated with ET, and 12.4 months for those treated with TEX (HR 0.84, 95% CI 0.65-1.07, P = 0.16); median OS was 26.0 months for women in the ET versus 29.7 months in the TEX arm (HR 0.84, 95% CI 0.63-1.11, P = 0.22). OR was achieved in 44.8% (ET) and 54.2% (TEX), respectively (χ(2) 3.66, P = 0.16). TTF was significantly longer for patients treated with TEX, 6.0 months, versus 5.2 months following ET (HR 0.73, 95% CI 0.58-0.93, P = 0.009). Severe hematological side effects related to epirubicin and paclitaxel were evenly distributed between the treatment arms, mucositis, diarrhea, and Hand-Foot syndrome were significantly more frequent in the TEX arm. Toxicity-adjusted treatment with ET and TEX showed similar efficacy in terms of PFS, OS, and OR. In this trial with limited power, the addition of capecitabine to epirubicin and paclitaxel as first-line treatment did not translate into clinically relevant improvement of the outcome.

Inactivation of promoter 1B of APC causes partial gene silencing: evidence for a significant role of the promoter in regulation and causative of familial adenomatous polyposis.

Familial adenomatous polyposis (FAP) is caused by germline mutations in the adenomatous polyposis coli (APC) gene. Two promoters, 1A and 1B, have been recognized in APC, and 1B is thought to have a minor role in the regulation of the gene. We have identified a novel deletion encompassing half of this promoter in the largest family (Family 1) of the Swedish Polyposis Registry. The mutation leads to an imbalance in allele-specific expression of APC, and transcription from promoter 1B was highly impaired in both normal colorectal mucosa and blood from mutation carriers. To establish the significance of promoter 1B in normal colorectal mucosa (from controls), expression levels of specific transcripts from each of the promoters, 1A and 1B, were examined, and the expression from 1B was significantly higher compared with 1A. Significant amounts of transcripts generated from promoter 1B were also determined in a panel of 20 various normal tissues examined. In FAP-related tumors, the APC germline mutation is proposed to dictate the second hit. Mutations leaving two or three out of seven 20-amino-acid repeats in the central domain of APC intact seem to be required for tumorigenesis. We examined adenomas from mutation carriers in Family 1 for second hits in the entire gene without any findings, however, loss of the residual expression of the deleterious allele was observed. Three major conclusions of significant importance in relation to the function of APC can be drawn from this study; (i) germline inactivation of promoter 1B is disease causing in FAP; (ii) expression of transcripts from promoter 1B is generated at considerable higher levels compared with 1A, demonstrating a hitherto unknown importance of 1B; (iii) adenoma formation in FAP, caused by impaired function of promoter 1B, does not require homozygous inactivation of APC allowing for alternative genetic models as basis for adenoma formation.

Paclitaxel, Epirubicin and Capecitabine (TEX) as First-Line Treatment for Metastatic Breast Cancer: a Pilot Phase I/II Feasibility Study.

Thirteen patients with untreated metastatic breast cancer received epirubicin 60 mg/m(2), paclitaxel 155 mg/m(2) (both day 1) and capecitabine 665 mg/m(2) twice daily (days 1-14) every 21 days, with intra-patient dose escalation/reduction. Grade 3/4 events were infrequent. Nine patients (69%) achieved an objective response. Median time to progression and overall survival were 6.6 and 23.5 months, respectively.

A founder mutation of the BRCA1 gene in Western Sweden associated with a high incidence of breast and ovarian cancer.

The aim of this study was to describe and characterise a founder mutation of the BRCA1 gene in western Sweden. Of 62 families screened for BRCA mutations, 24 had BRCA1 mutations and two had BRCA2 mutations. Tumours that occurred in family members were histologically reviewed and mutational status was analysed using archival paraffin-embedded tissues. The same BRCA1 mutation, 3171ins5, was found in 16 families who were clustered along the western coast of Sweden. Mutation analysis revealed a maternal linkage in 13 families and a paternal linkage in 3. There was complete agreement between mutation analysis results obtained from blood and archival tissues. The penetrance of breast or ovarian cancer by age 70 years was estimated to be between 59 and 93%. There were no differences in survivals between breast or ovarian cancer patients with the mutation and age-matched controls. Thus, a predominant BRCA1 gene founder mutation associated with a high risk of breast and ovarian cancer has been identified and found to occur in a restricted geographical area, thereby allowing timely and cost-effective mutation screening using blood samples or archival histological material.

Supra-additive cytotoxic effects of a combination of cytostatic drugs and antibody-induced complement activation on tumor cells in vitro.

Chemotherapy with cytostatic and cytotoxic drugs is the main treatment modality for disseminated cancer. However, despite initial clinical responses seen in certain histotypes, such as small cell lung cancer, relapses mostly occur with chemoresistant phenotypes. In order to prolong the relapse-free period, a combination of chemo- and immunotherapy might offer a new treatment strategy. Here, we have tested our hypothesis that complement activation, induced by monoclonal antibodies, in combination with cytostatic drugs may result in additive cytotoxicity in vitro. Doxorubicin, cisplatinum and etoposide were tested in combination with human complement and a murine monoclonal antibody (MAb F12) directed against the tumor-associated ganglioside antigen fucosyl GM1 on a rat hepatoma (H4-II-E) cell line which was used as tumor model. Using the MTT assay to measure cell survival, supra-additive (i.e. synergistic) cytotoxic effects were seen with each of the cytostatic drugs, the strongest being observed with doxorubicin. These results show promise for further research exploring possible prognostically favorable interactions between cytostatic drugs and monoclonal antibodies in the treatment of cancer.

The western Swedish BRCA1 founder mutation 3171ins5; a 3.7 cM conserved haplotype of today is a reminiscence of a 1500-year-old mutation.

The most recurrent BRCA1/BRCA2 mutation in Sweden is the BRCA1 mutation 3171ins5. In the western part of Sweden this mutation accounts for as much as 77% of identified mutations in these two genes. Our aim was to analyse in detail the haplotype and founder effects of the 3171ins5 and furthermore attempt to estimate the time of origin of the mutation. In the study we included eighteen apparently unrelated families with hereditary breast and/or ovarian cancer. At least one individual in each family had previously tested positive for the 3171ins5 mutation. Polymorphic microsatellite markers were used for the haplotype analyses. The markers were located within or flanking the BRCA1 gene spanning a region of 17.3 cM. We found several different haplotypes both for disease alleles and for the normal alleles. However, a conserved haplotype of 3.7 cM was observed in the 3171ins5 carriers spanning over four markers located within or very close to the BRCA1 gene. As this haplotype was not present in any of the normal controls it is highly likely that this is a mutation identical by descent, i.e. a true founder. The results from the haplotype analyses were used to estimate the age of the mutation. Estimations based on the P(excess) and linkage disequilibrium gives a first appearance of the mutation sometime around the 6th century, approximately 50 generations ago.

Functional assessment in vitro of human-complement-dependent antibody-induced cytotoxicity of neoplastic cells.

The complement system is one potential cytotoxic effector mechanism that might be effective in immunotherapy of cancer using monoclonal antibodies (mAb) directed against tumor antigens. In order to evaluate the treatment outcome from trials using mAb in cancer patients, assessment of complement-dependent cytotoxicity (CDC) may therefore be of interest. Here we describe the elaboration of a CDC assay in vitro using a rat hepatoma cell line, H4-II-E, as target cells sensitised with mAb F12, directed against the tumor-associated ganglioside antigen fucosyl-GMI. Sensitised cells were incubated with various concentrations of fresh serum as complement source for 48 h and cytotoxicity was then assessed by the tetrazolium bromide (MTT) test. A large variation in CDC efficacy was observed between individual serum donors. No differences in CDC could be seen between healthy donors and cancer patients. The CDC showed a strong correlation to the serum concentrations of complement factor C4, supporting the validity of the assay. Our results suggest that there may be significant variations in complement function within and between individuals that might influence the outcome of clinical mAb therapy. The H4/F12 CDC assay described here, together with measurement of individual complement factors. such as C4, should be further validated in cancer patients at various disease stages and phases of treatment.

Prognosis and clinical presentation of BRCA2-associated breast cancer.

54 female breast cancer patients from 22 families with BRCA2 germ line mutations from Sweden and Denmark were compared with 214 age- and date of diagnosis-matched controls identified among breast cancer patients from South Sweden. At diagnosis, BRCA2-associated cases were more often node-positive (N+). OR=1.9 (95% confidence interval (CI)=1.0-3.6; P=0.036), and were more often clinical stage IV: OR=4.6 (95% CI=1.3-17; P=0.021) than the controls. Bilateral disease was also more common among the BRCA2-associated cases: OR=2. 4 (95% CI=1.1-5.3; P=0.027). Breast cancer-specific survival (BCSS) was significantly worse among the BRCA2-associated cases: RR=2.0 (95% CI=1.2-3.4; P=0.010). When stage was corrected for in a multivariate analysis, BCSS was no longer significantly worse for the BRCA2-associated cases: RR=1.6 (95% CI=0.85-3.1). The corresponding effect after correction for bilateral disease was: RR=1.8 (95% CI=1.0-3.1; P=0.034). The unfavourable prognosis in BRCA2-associated breast cancer seems, to a great extent, to be a consequence of the higher clinical stage at diagnosis. The increased presence of bilateral cancers appears to have less impact on survival in this group of hereditary breast cancer. Data presented here needs to be taken into account when counselling healthy carriers of BRCA2 germ line mutations.