Relationship between tumour shrinkage and reduction in Ki67 expression after primary chemotherapy in human breast cancer

The association between tumour shrinkage and reduction in kinetic cell activity after primary chemotherapy in human breast cancer is still a matter of investigation. 157 patients with T2-4, N0-1, M0 breast cancer received primary chemotherapy consisting of either the CMF regimen + tamoxifen (the first consecutive 76 cases) or the single agent epirubicin (the subsequent 81). Ki67, p53, bcl2, c-erbB2 and steroid hormone receptors were evaluated immunohistochemically in tumour specimens obtained before chemotherapy and at surgery. Tumour shrinkage of >50% occurred in 72.4% of patients. Ki67 expression significantly decreased after chemotherapy; the reduction correlated with tumour response in both univariate (P < 0.005) and multivariate analysis (P = 0.02). p53, bcl-2, steroid hormone receptor and c-erbB2 immunostaining were scarcely affected. Baseline bcl2 (P = 0.04) and c-erbB2 (P = 0.02) were directly and inversely associated with the reduction in Ki67 immunostaining, respectively. Baseline p53 expression (P < 0.01) was directly related with Ki67 expression at residual tumour, whereas oestrogen receptor expression (P < 0.001) was inversely related. Ki67 at residual tumour was a better predictor for relapse-free survival (RFS) than baseline Ki67. Clinical response (P < 0.03), but not reduction in Ki67, was a significant independent predictor for disease recurrence. Chemotherapy was found to induce tumour shrinkage and to reduce the number of cells in the cell cycle, but its effect on tumour biology/aggressiveness was minimal. Reduction in Ki67 immunostaining correlated with clinical response but failed to be related to RFS. Ki67 expression at surgery rather than at baseline appears to be a better predictor for disease relapse. © 2001 Cancer Research Campaign  http://www.bjcancer.co

A phase II multi-institutional study assessing simultaneous in-field boost helical tomotherapy for 1-3 brain metastases

<p>Abstract</p> <p>Background</p> <p>Our research group has previously published a dosimetric planning study that demonstrated that a 60 Gy/10 fractions intralesional boost with whole-brain radiotherapy (WBRT) to 30 Gy/10 fractions was biologically equivalent with a stereotactic radiosurgery (SRS) boost of 18 Gy/1 fraction with 30 Gy/10 fractions WBRT. Helical tomotherapy (HT) was found to be dosimetrically equivalent to SRS in terms of target coverage and superior to SRS in terms of normal tissue tolerance. A phase I trial has been now completed at our institution with a total of 60 enrolled patients and 48 evaluable patients. The phase II dose has been determined to be the final phase I cohort dose of 60 Gy/10 fractions.</p> <p>Methods/Design</p> <p>The objective of this clinical trial is to subject the final phase I cohort dose to a phase II assessment of the endpoints of overall survival, intracranial control (ICC) and intralesional control (ILC). We hypothesize HT would be considered unsuitable for further study if the median OS for patients treated with the HT SIB technique is degraded by 2 months, or the intracranial progression-free rates (ICC and ILC) are inferior by 10% or greater compared to the expected results with treatment by whole brain plus SRS as defined by the RTOG randomized trial. A sample size of 93 patients was calculated based on these parameters as well as the statistical assumptions of alpha = 0.025 and beta = 0.1 due to multiple statistical testing. Secondary assessments of toxicity, health-related quality-of-life, cognitive changes, and tumor response are also integrated into this research protocol.</p> <p>Discussion</p> <p>To summarize, the purpose of this phase II trial is to assess this non-invasive alternative to SRS in terms of central nervous system (CNS) control when compared to SRS historical controls. A follow-up phase III trial may be required depending on the results of this trial in order to definitively assess non-inferiority/superiority of this approach. Ultimately, the purpose of this line of research is to provide patients with metastatic disease to the brain a shorter course, dose intense, non-invasive radiation treatment with equivalent or improved CNS control/survival and health-related quality-of-life/toxicity profile when compared to SRS radiotherapy.</p> <p>Trial registration</p> <p>Clinicaltrials.gov - <a href="http://www.clinicaltrials.gov/ct2/show/NCT01543542">NCT01543542</a>.</p

Pretreatment haemoglobin levels significantly predict the tumour response to primary chemotherapy in human breast cancer

The purpose of this study was to evaluate whether tumour response to primary chemotherapy in human breast cancer is influenced by baseline haemoglobin (Hb) status. A total of 157 patients with T2-4, N0-1 M0 breast cancer were treated with chemotherapy consisting of either the CMF regimen + tamoxifen (the first 76 cases) or the single-agent epirubicin (the subsequent 81) before definitive surgery. In total, 144 patients were fully assessable. Ki67, p53, bcl-2, c-erbB2, steroid hormone receptor, and microvessel density were evaluated immunohistochemically in tumour specimens obtained before chemotherapy and at surgery. Tumour shrinkage >50% occurred in 72.1% of patients. Responding patients had higher baseline Hb levels and red blood cell counts than nonresponders (P<0.01 and <0.003, respectively). The distribution of disease response according to increasing cutoffs of baseline Hb status showed that from 12.5 mg l(-1) onwards, patients with Hb levels above the cutoff obtained a greater response rate than those with lower Hb values. The difference attained the statistical significance at 12.5 (76.1 vs 59.5%, P<0.05) and 13.0 g/dl(-1) (81.0 vs 57.6%, P<0.002) cutoffs, respectively. The predictive role of Hb levels was maintained in multivariate analysis after adjustment for clinical and biological characteristics and treatment regimen. Patients with baseline Hb levels </=13 g dl(-1) showed a lower treatment-induced reduction in Ki67 expression (P<0.04) and a higher Ki67 expression at postoperative evaluation (P<0.02) than their counterparts. In conclusion, low Hb levels may negatively influence the response rate of chemotherapy in breast cancer patients. Inhibition of antiproliferative activity could be a possible mechanism

Assessing the quality of proton PBS treatment delivery using machine log files: comprehensive analysis of clinical treatments delivered at PSI Gantry 2.

Pencil beam scanning (PBS) proton therapy requires the delivery of many thousand proton beams, each modulated for position, energy and monitor units, to provide a highly conformal patient treatment. The quality of the treatment is dependent on the delivery accuracy of each beam and at each fraction. In this work we describe the use of treatment log files, which are a record of the machine parameters for a given field delivery on a given fraction, to investigate the integrity of treatment delivery compared to the nominal planned dose. The dosimetry-relevant log file parameters are used to reconstruct the 3D dose distribution on the patient anatomy, using a TPS-independent dose calculation system. The analysis was performed for patients treated at Paul Scherrer Institute on Gantry 2, both for individual fields and per series (or plan), and delivery quality was assessed by determining the percentage of voxels in the log file dose distribution within  +/-  1% of the nominal dose. It was seen that, for all series delivered, the mean pass rate is 96.4%. Furthermore, this work establishes a correlation between the delivery quality of a field and the beam position accuracy. This correlation is evident for all delivered fields regardless of individual patient or plan characteristics. We have also detailed further usefulness of log file analysis within our clinical workflow. In summary, we have highlighted that the integrity of PBS treatment delivery is dependent on daily machine performance and is specifically highly correlated with the accuracy of beam position. We believe this information will be useful for driving machine performance improvements in the PBS field

Effect of neoadjuvant chemotherapy on Ki67 labelling index, c-erbB-2 expression and steroid hormone receptor status in human breast tumours.

The administration of neoadjuvant chemotherapy to breast cancer (BC) patients with operable disease allowed studies aimed of exploring the interaction between cytotoxic treatment and tumour biology in vivo. 99 patients with T2-4, NO-1, M0 primary BC received a median of 3 cycles of either CMF regimen (cyclophosphamide, methotrexate, 5-fluorouracil) or single agent epirubicin. Endocrine therapy was also concomitantly administered in the first 45 patients with estrogen receptor positive (ER+) BC. 92 ended the treatment plan. Ki67 labelling index, estrogen receptor (ER), progesterone receptor (PgR), and c-erbB-2 oncoprotein expression were evaluated immunohistochemically in tumour biopsies obtained before and after chemotherapy. At post-chemotherapy evaluation, tumour shrinkage greater than 50% was obtained in 71 patients (79.7%), 27 of them being complete responders (30.3%). The median Ki67 labelling index, which was 13% in the first biopsy, decreased to 4.5% (p < 0.001) upon mastectomy. No significant differences were observed in steroid hormone receptor and c-erbB-2 expression before and after neoadjuvant treatment. In conclusion, neoadjuvant chemotherapy, whether associated or not to endocrine therapy, leads to a significant decrease in BC proliferation without any appreciable impact on c-erbB-2 and steroid hormone receptor expression

Changes in microvessel density as assessed by CD34 antibodies after primary chemotherapy in human breast cancer.

BACKGROUND: Several papers have shown that quantitationof tumor angiogenesis in primary breast cancer by counting blood vessels gives an independent assessment of prognosis. The impact of chemotherapy +/- endocrine therapy on the extent of angiogenesis is unknown. METHODS: Matched pair histological tumor samples were obtained before and after primary chemotherapy from 120 breast cancer patients recruited in the same institution. The first 55 cases received cyclophosphamide, methotrexate, and 5-fluorouracil +/- Tamoxifen, whereas the subsequent 65 were submitted to single agent epirubicin. Patients underwent an incisional biopsy at diagnosis and definitive surgery on completion of three or four chemotherapy cycles. Microvessel density (MVD) was performed after staining with the CD34 monoclonal antibody. RESULTS: MVD slightly decreased after chemotherapy [median 51.26 mm(2) (range 2.33-163.1) and 44.27 mm(2) (2.33-121.16; P < 0.001)]; this small reduction neither correlated with tumor response nor with changes in Ki67 expression. MVD at baseline significantly correlated with MVD assessed at definitive surgery (Spearman r = 0.70, P < 0.001). In multivariate analysis, c-erbB2 status showed an independent role in predicting the reduction in MVD that just failed to attain the statistical significance (P = 0.08), whereas baseline parameters, such as T, N, steroid hormone receptor, bcl-2, p53, c-erbB2, and Ki67 expression, did not enter the model. CONCLUSIONS: Primary chemotherapy is able to modestly reduce the MVD in breast tumors. This small change is not biologically important, because the baseline neoangiogenesis status is not substantially changed. The change in microvessel count after chemotherapy could be potentially influenced by the c-erbB2 status