Using proliferative markers and Oncotype DX in therapeutic decision-making for breast cancer: the B.C. experience.

BACKGROUND: Proliferative scoring of breast tumours can guide treatment recommendations, particularly for estrogen receptor (er)-positive, her2-negative, T1-2, N0 disease. Our objectives were to □ estimate the proportion of such patients for whom proliferative indices [mitotic count (mc), Ki-67 immunostain, and Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.) recurrence score (rs)] were obtained.□ compare the indices preferred by oncologists with the indices available to them.□ correlate Nottingham grade (ng) and its subcomponents with Oncotype dx.□ assess interobserver variation. METHODS: All of the er-positive, her2-negative, T1-2, N0 breast cancers diagnosed from 2007 to 2011 (n = 5110) were linked to a dataset of all provincial breast cancers with a rs. A 5% random sample of the 5110 cancers was reviewed to estimate the proportion that had a mc, Ki-67 index, and rs. Correlation coefficients were calculated for the rs with ng subcomponent scores. Interobserver variation in histologic grading between outside and central review pathology reports was assessed using a weighted kappa test. RESULTS: During 2007-2011, most cancers were histologically graded and assigned a mc; few had a Ki-67 index or rs. The ng and mc were significantly positively correlated with rs. The level of agreement in histologic scoring between outside and central pathology reports was good or very good. Very few cases with a low mc had a high rs (1.8%). CONCLUSIONS: Patients with low ng and mc scores are unlikely to have a high rs, and thus are less likely to benefit from chemotherapy. In the context of limited resources, that finding can guide clinicians about when a rs adds the most value.

The Effect of Breast Cancer Subtype on Symptom Improvement Following Palliative Radiotherapy for Bone Metastases.

AIM: To assess the relationship between breast cancer subtypes and patient-reported outcomes (PRO) following palliative radiotherapy for bone metastases. MATERIALS AND METHODS: Prospectively collected PRO for all breast cancer patients treated with palliative, bone metastasis-directed radiotherapy from 2013 to 2016 in the province of British Columbia were analysed. The PRO questionnaire scored pain severity, level of function and symptom frustration at baseline and at 3-4 weeks following palliative radiotherapy using a 12-point scale. The primary outcome was the rate of overall response (any improvement in score); the secondary outcome was the rate of complete improvement in PRO (final PRO score of 0). Multivariate logistic analysis was used to compare response rates between molecular subgroup approximations of luminal A (LumA), luminal B (LumB), HER2-enriched (HER2) and triple negative (TN), as defined by grade and immunohistochemical staining. RESULTS: There were 376 patients who underwent 464 courses of palliative radiation for bone metastases. Subtypes included: 243 LumA, 146 LumB, 46 HER2 and 29 TN. There were 216 multifraction radiotherapy courses (median dose 20 Gy) and 248 single-fraction radiotherapy courses (median dose 8 Gy). The overall response rate was 85% and the complete response rate was 25%. In comparison with LumA breast cancers, TN breast cancers were associated with a lower rate of overall response (69% versus 86%, P = 0.021) and a lower rate of complete response (10% versus 28.8%, P = 0.045) on multivariate analyses. CONCLUSION: Patients with TN breast cancer have lower rates of pain, function and symptom frustration improvement following palliative radiation for bone metastases.

Impact of pathologic complete response on survival after neoadjuvant chemotherapy in early-stage breast cancer: a population-based analysis.

BACKGROUND: Achieving a pathologic complete response (pCR) has been associated with improved long-term outcomes in clinical trials. However, the benefit of achieving pCR across subtypes and its prognostic effect on real-world outcomes has not been well described. METHODS: A retrospective analysis of the Breast Cancer Outcomes Unit database was undertaken to identify patients with stage I-III breast cancer treated with neoadjuvant chemotherapy from 2005 to 2010 in British Columbia. Patients were separated into two groups: those with pCR and those with residual invasive disease in the breast/axillary lymph nodes (RD). The primary endpoint was relapse-free survival (RFS). Key secondary endpoints included breast cancer-specific survival (BCSS) and overall survival (OS). RESULTS: Of 267 patients identified, 74 patients (28%) achieved pCR and 193 patients (72%) had RD. Median follow-up was 7.5 years. The 5-year RFS was higher in the pCR group compared to the RD group (84% vs 70%; HR 0.45, p = 0.011). The 5-year BCSS was also higher in the pCR group than in the RD group (90% vs 77%; HR 0.39, p = 0.014). In multivariable analyses, pCR was associated with improved RFS (HR 0.39, p = 0.0077) and BCSS (HR 0.35, p = 0.015), whereas traditional pathological prognostic factors were not. Patients with TNBC who achieved pCR had improved RFS and BCSS compared to those with RD (HR 0.26, p = 0.020 and HR 0.35, p = 0.090, respectively). A similar but non-statistically significant trend was seen in the HER-2-positive and ER + subtypes. CONCLUSIONS: Achieving pCR after neoadjuvant chemotherapy was associated with clinically meaningful improvements in survival parameters in a real-world setting. The cumulative data support pCR as a valid surrogate endpoint in both clinical trials and population-based settings.

Impact of Recurrence Score on type and duration of chemotherapy in breast cancer.

Background: The use of Oncotype dx (Genomic Health, Redwood City, CA, U.S.A.) testing has been shown to change treatment decisions in approximately 30% of breast cancer (bca) cases, but research on how Recurrence Score testing has affected the type of chemotherapy offered is limited. We sought to determine if the availability of Oncotype dx testing resulted in a change to the type and duration of chemotherapy regimens used in the treatment of early-stage hormone receptor-positive bca. Methods: In a population-based cohort study, patients treated in the 2 years before the availability of Oncotype dx testing were compared with patients treated in the 2 years after testing availability. Charts were audited and divided into 2 groups: pre-Oncotype dx and post-Oncotype dx. The groups were compared for differences in duration of chemotherapy (12 weeks vs. >12 weeks), types of agents used (anthracycline vs. non-anthracycline), and myelosuppressive potential of the chosen regimen. Results: Of 834 patients who fulfilled the enrolment criteria, 360 fell into the pre-Oncotype dx era, and 474, into the post-Oncotype dx era. An increase of 11.2 percentage points, to 69.5% from 58.3%, was observed in the proportion of patients receiving short-course compared with long-course chemotherapy (p = 0.068). The proportion of patients prescribed anthracycline-containing regimens declined in the post-Oncotype dx era (47.7% pre vs. 32.2% post, p = 0.016). The selection of more-myelosuppressive chemotherapy protocols increased in the post-Oncotype dx era (67.4% pre vs. 78.8% post, p = 0.044). Conclusions: In the present study, the availability of Oncotype dx testing was observed to influence the choice of chemotherapy type in the setting of early-stage bca.

Relationship between tumor location and relapse in 6,781 women with early invasive breast cancer.

PURPOSE: To explore the independent prognostic impact of medial hemisphere tumor location in early breast cancer. PATIENTS AND METHODS: A comprehensive database was used to review patients referred to the British Columbia Cancer Agency from 1989 to 1995 with early breast cancer. Patients were grouped according to relapse risk (high or nonhigh) and adjuvant systemic therapy received. Multiple regression analysis was used to determine whether the significance of primary tumor location (medial v lateral hemisphere) was independent of known prognostic factors and treatment. RESULTS: In the adjuvant systemic therapy groups, medial location was associated with a 50% excess risk of systemic relapse and breast cancer death compared with lateral location. Five-year systemic disease-free survival rates were 66.3% and 74.2% for high-risk medial and lateral lesions, respectively (P <.005). Corresponding 5-year disease-specific survival rates were 75.7% and 80.8%, respectively (P <.03). No significant differences were observed between medial and lateral location for low-risk disease regardless of adjuvant therapy or for high-risk disease with no adjuvant therapy. Local recurrence rates were similar for all risk and therapy groups. CONCLUSION: The two-fold risk of relapse and breast cancer death associated with high-risk medial breast tumors may be due to occult spread to internal mammary nodes (IMNs). Enhanced local control, such as with irradiation of the IMN chain, may be one way to reduce the excess risk. Ongoing randomized controlled trials may provide prospective answers to the question of the optimal volume of radiotherapy.

Doxorubicin and paclitaxel versus doxorubicin and cyclophosphamide as first-line chemotherapy in metastatic breast cancer: The European Organization for Research and Treatment of Cancer 10961 Multicenter Phase III Trial.

PURPOSE: To compare the efficacy and tolerability of the combination of doxorubicin and paclitaxel (AT) with a standard doxorubicin and cyclophosphamide (AC) regimen as first-line chemotherapy for metastatic breast cancer. PATIENTS AND METHODS: Eligible patients were anthracycline-naive and had bidimensionally measurable metastatic breast cancer. Two hundred seventy-five patients were randomly assigned to be treated with AT (doxorubicin 60 mg/m(2) as an intravenous bolus plus paclitaxel 175 mg/m(2) as a 3-hour infusion) or AC (doxorubicin 60 mg/m(2) plus cyclophosphamide 600 mg/m(2)) every 3 weeks for a maximum of six cycles. A paclitaxel (200 mg/m(2)) and cyclophosphamide (750 mg/m(2)) dose escalation was planned at cycle 2 if no grade >or= 3 neutropenia occurred in cycle 1. The primary efficacy end point was progression-free survival (PFS). Secondary end points were response rate (RR), safety, overall survival (OS), and quality of life. RESULTS: A median number of six cycles were delivered in the two treatment arms. The relative dose-intensity and delivered cumulative dose of doxorubicin were lower in the AT arm. Dose escalation was only possible in 17% and 20% of the AT and AC patients, respectively. Median PFS was 6 months in the two treatments arms. RR was 58% versus 54%, and median OS was 20.6 versus 20.5 months in the AT and AC arms, respectively. The AT regimen was characterized by a higher incidence of febrile neutropenia, 32% versus 9% in the AC arm. CONCLUSION: No differences in the efficacy study end points were observed between the two treatment arms. Treatment-related toxicity compromised doxorubicin-delivered dose-intensity in the paclitaxel-based regimen

Taxanes in the adjuvant treatment of breast cancer: why not yet?

The taxanes paclitaxel and docetaxel represent the most active chemotherapeutic agents developed for the treatment of advanced breast cancer in the last decade, and they are now being incorporated into adjuvant chemotherapy trials for lymph node-positive breast cancer with the hope of improving on the results achieved with CMF (cyclophosphamide, methotrexate, 5-fluorouracil) or anthracycline-based regimens. So far, three randomized paclitaxel-based adjuvant clinical trials enrolling 3170 women (Cancer and Leukemia Group B [CALGB] 9344), 3060 women (National Surgical Adjuvant Project for Breast and Bowel Cancers [NSABP]-B28), and 524 women (M. D. Anderson), respectively, have been reported with respective median follow-up times of 52, 34, and 43 months. This article critically reviews these three studies and gives an overview of the many other randomized clinical trials, due to accrue more than 17 000 women, which are investigating the potential of taxanes in adjuvant breast cancer therapy. Given that the early promise of taxanes suggested by CALGB 9344 is not yet confirmed by the two other trials, only level 2 evidence has been reached to date in regard to a positive contribution of these agents to breast cancer outcome in the adjuvant setting. It is argued that level 1 evidence is highly desirable before adopting taxane-based regimens in standard practice. It is anticipated that a meta-analysis will be needed to comprehensively define the value of taxanes in early breast cancer, and a new model of international collaboration is proposed to find a balance between the need to offer new, more effective therapies to patients as soon as possible and the danger of drawing wrong, premature conclusions regarding the magnitude of benefit of a new regimen.

An EORTC-IDBBC phase I study of gemcitabine and continuous infusion 5-fluorouracil in patients with metastatic breast cancer resistant to anthracyclines or pre-treated with both anthracyclines and taxanes.

The aim of this study was to determine the maximum tolerated dose (MTD), dose-limiting toxicities (DLT), and potential activity of combined gemcitabine and continuous infusion 5-fluorouracil (5-FU) in metastatic breast cancer (MBC) patients that are resistant to anthracyclines or have been pretreated with both anthracyclines and taxanes. 15 patients with MBC were studied at three European Organization for Research and Treatment of Cancer centres. 13 patients had received both anthracylines and taxanes. Gemcitabine was given intravenously (i.v.) on days 1 and 8, and 5-FU as a continuous i.v. infusion on days 1 through to 14, both drugs given in a 21-day schedule at four different dose levels. Both were given at doses commonly used for the single agents for the last dose level (dose level 4). One of 6 patients at level 4 (gemcitabine 1200 mg/m2 and 5-FU 250 mg/m2/day) had a DLT, a grade 3 stomatitis and skin toxicity. One DLT, a grade 3 transaminase rise and thrombosis, occurred in a patient at level 2 (gemcitabine 1000 mg/m2 and 5-FU 200 mg/m2/day). Thus, the MTD was not reached. One partial response and four disease stabilisations were observed. Only 1 patient withdrew from the treatment due to toxicity. The MTD was not reached in the phase I study. The combination of gemcitabine and 5-FU is well tolerated at doses up to 1200 mg/m2 given on days 1 and 8 and 250 mg/m2/day given on days 1 through to 14, respectively, every 21 days. The clinical benefit rate (responses plus no change of at least 6 months) was 33% with one partial response, suggesting that MBC patients with prior anthracycline and taxane therapy may derive significant benefit from this combination with minimal toxicity.

An overview of HER2.

HER2 is a transmembrane growth factor receptor found in normal and malignant breast epithelial cells. Phosphorylation of the intracellular tyrosine kinase results in intracellular signaling and activation of genes involved in cell growth. Overexpression of HER2 has independent prognostic significance in early breast cancer and may also predict response to hormonal and cytotoxic therapies, although this latter role is less well studied. Prospective stratification of HER2 status in current clinical trials may more accurately delineate these roles. Anti-HER2 therapy, using a humanized monoclonal antibody, has enhanced survival when given with chemotherapy compared with chemotherapy alone in patients with metastatic HER2-overexpressing breast cancer. A potential limitation to its use in the adjuvant setting is the increased incidence of cardiotoxicity in patients treated either concurrently or previously with anthracyclines; carefully designed prospective adjuvant trials are currently being launched. HER2 is a relatively new prognostic marker and holds promise for predicting response to various therapies and for target-specific therapy.

HER2/neu as a predictive factor in breast cancer.

One of the current trends in breast cancer research is to identify markers that can predict response to specific anticancer therapies; intense laboratory research and therapeutic trials are exploiting this strategy. The combination of cytotoxic drugs directed at the tumor population with the highest probability of being sensitive to them with molecules targeted at intracellular signaling and cell cycle control pathways, which may be deregulated as part of the malignant process, represents our best hope for improved survival in both early and advanced disease. The transmembrane tyrosine kinase receptor, HER2/neu, has been the subject of much investigation with respect to its prognostic value, predictive value, and as a target of antibody-mediated therapy. Retrospective evidence strongly suggests that HER2 overexpression is associated with decreased disease-free and overall survival in node-positive, and possibly also node-negative, breast cancer. Prospective trials have demonstrated that antibodies to HER2 can produce tumor responses in women with advanced disease that overexpresses this molecule. Moreover, the combination of such antibodies with cytotoxic drugs has been one of the few recent strategies to improve survival duration in metastatic breast cancer. The evidence supporting the role of HER2 as a factor predictive of response to hormone therapy and cytotoxic drugs is more ambiguous and requires prospective assessment. The available literature is reviewed herein, with a focus on the predictive value of HER2, potential mechanisms of resistance and sensitivity to various drugs, and future research directions involving this important molecule.

Promising results with exemestane in the first-line treatment of metastatic breast cancer: a randomized phase II EORTC trial with a tamoxifen control.

Because tamoxifen (TAM), a nonsteroidal antiestrogen, is routinely used in the adjuvant setting, other hormone therapies are needed as alternatives for first-line treatment of metastatic breast cancer (MBC). Currently, exemestane (EXE) and other antiaromatase agents are indicated for use in patients who experience failure of TAM. In this multicenter, randomized, open-label, TAM-controlled (20 mg/day), phase II trial, we examined the activity and tolerability of EXE 25 mg/day for the first-line treatment of MBC in postmenopausal women. Exemestane was well tolerated and demonstrated substantial first-line antitumor activity based on intent-to-treat analysis of peer-reviewed responses. In the EXE arm, values for complete, partial, and objective response, clinical benefit, and time to tumor progression (TTP) exceeded those reported for TAM although no statistical comparison was made. Based on these encouraging results, a phase III trial will compare EXE and TAM.

Development of a biologically distinct EBV-related lymphoproliferative disorder following autologous bone marrow transplantation for an EBV-negative post-renal allograft Burkitt's lymphoma.

Post-transplant lymphoproliferative disorder (PTLD) is a known complication of both solid organ transplantation and allogeneic bone marrow transplantation (BMT) but is rarely seen following autologous BMT. We report the case of a 45 year-old female who developed Burkitt's lymphoma eight years after a renal allograft. This PTLD was found to have lambda light chain restriction, contained del(8)(q24) and add(14)(q32), and was negative for EBV on immunohistochemical and DNA-based PCR analyses. Immunoglobulin heavy chain (IgH) PCR studies revealed a prominent clonal rearrangement. She responded to intravenous cyclophosphamide and proceeded to high-dose chemoradiotherapy and mafosfamide-purged autologous BMT. Thirty-nine days post-BMT she presented with cough and fever and developed hepatic dysfunction; abnormal lymphoplasmacytoid cells were noted in the peripheral blood. Investigations revealed kappa light chain restriction, an oligoclonal IgH rearrangement, a normal karyotype and PCR studies for EBV were positive, consistent with a clinically and biologically distinct PTLD. She initially improved following discontinuation of immunosuppression, but then deteriorated abruptly and died 58 days post-BMT. It is likely that the two separate episodes of PTLD in this patient, one of which was atypical, arose as a result of both the chronic use of cyclosporine and the impairment of cell-mediated immunity associated with autologous BMT. The sequence of events in this patient should contribute to a better understanding of late-onset, EBV-negative PTLD.

A prospective clinical utility and pharmacoeconomic study of the impact of the 21-gene Recurrence Score® assay in oestrogen receptor positive node negative breast cancer.

PURPOSE: The primary purpose of this study was to measure the impact of the 21-gene Recurrence Score® result on systemic treatment recommendations and to perform a prospective health economic analysis in stage I-II, node-negative, oestrogen receptor positive (ER+) breast cancer. METHODS: Consenting patients with ER+ node negative invasive breast cancer and their treating medial oncologists were asked to complete questionnaires about treatment preferences, level of confidence in those preferences and a decisional conflict scale (patients only) after a discussion of their diagnosis and risk without knowledge of the Recurrence Score. At a subsequent visit, the assay result and final treatment recommendations were discussed prior to both parties completing a second set of questionnaires. A Markov health state transition model was constructed, simulating the costs and outcomes experienced by a hypothetical 'assay naïve' population and an 'assay informed' population. RESULTS: One hundred and fifty-six patients across two cancer centres were enrolled. Of the 150 for whom successful assay results were obtained, physicians changed their chemotherapy recommendations in 45 cases (30%; 95% confidence interval (CI) 22.8-38.0%); either to add (10%; 95% CI 5.7-16.0%) or omit (20%; 95% CI 13.9-27.3%) adjuvant chemotherapy. There was an overall significant improvement in physician confidence post-assay (p<0.001). Patient decisional conflict also significantly decreased following the assay (p<0.001). The simulation model found an incremental cost-effectiveness ratio of Canadian Dollars (CAD) $6630/quality-adjusted life years (QALY). CONCLUSION: Within the context of a publicly funded health care system, the Recurrence Score assay significantly affects adjuvant treatment recommendations and is cost effective in ER+ node negative breast cancer.

The predictive value of HER2 in breast cancer.

Measurement of molecular markers predictive of response to therapy should enable more selective and effective utilization of anticancer agents. The predictive value of HER2 remains a complex and inconclusive subject. In metastatic breast cancer, HER2-positive, ER-positive patients can show responses to endocrine treatment, but experience shorter time to progression and survival than HER2-negative patients. In the adjuvant setting, weak, retrospective evidence suggests that tamoxifen is potentially harmful in HER2-positive patients and that there is no benefit from prolonged tamoxifen therapy. It has not yet been demonstrated conclusively that HER2 positivity increases resistance to adjuvant cyclophosphamide, methotrexate, 5-FU (CMF), but there are indications that HER2-positive patients benefit more from adequately dosed anthracyclines than from CMF. The greatest value of HER2 as a predictive marker lies in the prediction of response to therapies that target HER2, such as Herceptin. Patients with strongly HER2-positive breast cancer derive significant clinical benefit from single-agent and combined Herceptin therapy. HER2 testing has become an integral part of the optimal management of the breast cancer patient. Best current practice in adjuvant breast cancer therapy based on the current knowledge of the potential predictive power of HER2 constitutes not denying tamoxifen to HER2-positive, ER-positive patients or CMF to HER2-positive patients. Outside of clinical trials, adequately dosed anthracycline-based chemotherapy is the current preferred adjuvant treatment option for HER2-positive patients.

Small cell carcinoma of the bladder: long term outcome with integrated chemoradiation.

BACKGROUND: Small cell carcinoma of the bladder (SCCB) is an uncommon tumor with approximately 8% 5-year survival reported in the literature for patients with disease confined to the pelvis. It exhibits biologic behavior similar to that of small cell carcinoma of the lung (SCLC). The authors sought to determine whether etoposide and cisplatin chemotherapy integrated with local irradiation is associated with improved survival in SCCB, as has been shown in SCLC. METHODS: The authors performed a retrospective analysis of stage, treatment, disease free survival (DFS), and overall survival (OS) among 14 British Columbia Cancer Agency (BCCA) patients treated between 1985 and 1996 for SCCB. RESULTS: When multiagent chemotherapy was combined with local irradiation, the authors observed a 70% 2-year and 44% 5-year actuarial OS among 10 patients without contraindications to systemic chemotherapy. Actuarial DFS was 70% at 2 and 5 years. The mean survival was 47 months (95% confidence interval, 18.5-76.1 months) and the median survival was 41 months. Nine of these patients had disease confined to the pelvis, and one had metastases to retroperitoneal lymph nodes. Five patients were alive and disease free an average of 82 months following diagnosis. Two patients had died of other causes without evidence of disease at 34 and 48 months following diagnosis. The incidence of second primary transitional cell bladder neoplasms following successful treatment was 60% at 2 years (3 of 5 long term survivors). CONCLUSIONS: Integrated chemoradiation for patients with limited stage SCCB generates a realistic expectation of long term survival. Prospective trials to confirm these findings are warranted.

Second and subsequent lines of chemotherapy for metastatic breast cancer: what did we learn in the last two decades?

Despite almost 30 years of clinical cancer research, the true impact of second and subsequent lines of chemotherapy on the outcome of metastatic breast cancer patients, especially on the duration of survival, is still unknown. In the virtually incurable metastatic setting, issues like quality of life and patients' preferences gain particular relevance. At the turn of the century, in-depth rethinking of the design of clinical trials run in this challenging disease setting appears to be warranted.

Mature results of a randomized phase II multicenter study of exemestane versus tamoxifen as first-line hormone therapy for postmenopausal women with metastatic breast cancer.

BACKGROUND: Women with hormone-responsive metastatic breast cancer (MBC) may respond to or have stable disease with a number of hormone therapies. We explored the efficacy and safety of the steroidal aromatase inactivator exemestane as first-line hormonal therapy in MBC in postmenopausal women. PATIENTS AND METHODS: Patients with measurable disease were eligible if they had received no prior hormone therapy for metastatic disease and had hormone receptor positive disease or hormone receptor unknown disease with a long disease-free interval from adjuvant therapy. They were randomized to tamoxifen 20 mg/day or exemestane 25 mg/day in this open-label study. RESULTS: Blinded independently reviewed response rates for exemestane and tamoxifen were 41% and 17%, respectively. Fifty-seven per cent of exemestane- and 42% of tamoxifen-treated patients experienced clinical benefit, defined as complete or partial response, or disease stabilization lasting at least 6 months. There was a low incidence of severe flushing, sweating, nausea and edema in women who received exemestane. One exemestane-treated patient had a pulmonary embolism with grade 4 dyspnea. CONCLUSIONS: Exemestane is well tolerated and active in the first-line treatment of hormone-responsive MBC. An ongoing EORTC phase III trial is comparing the efficacy, measuring time-to-disease progression, of exemestane and tamoxifen.