The neoadjuvant management of bladder cancer in Canada: A survey of genitourinary medical oncologists

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Background: The uptake of neoadjuvant chemotherapy (NC) for the treatment of stage II/III bladder cancer remains variable despite evidence supporting its use. The aim of this study is to better understand the use of NC in Canada to facilitate standardization of practice and develop a platform for clinical trials.

Methods: The survey was initially tested on a subset of medical oncologists. It was then e-mailed to 30 medical oncologists across Canada who primarily treat bladder cancer.

Results: In total, 25 (83%) surveys were completed. Respondents were 92% academic based, 100% full time, and 52% in practice for >10 years. The majority of referrals for all stages came from urologists with 4 respondents (16%) seeing 5-10 cases/yr, 10 (40%) seeing 11-15/yr, 5 (20%) seeing 16- 20/yr and 6 (24%) seeing >20/yr. Of these 8 reported having only 1-2 referrals for NC; 7 had 3-4 NC referrals; 7 had 5-6 NC referrals; and 2 reported seeing >6 referrals/year. Patients referred for NC tended to be younger (50-65); Performance Status (PS) 0/1; T-stage T3a/T3b; or nodal status N1/N2. 96% indicated they do offer NC to selected patients as both standard of care and to downsize tumors. Key factors cited for not offering NC were: Age >85, PS 3/4; T-stage T2a or T4a; Nodal status: N3; GFR <40ml/min. Main baseline staging modalities included CT chest/abdomen/pelvis, bone scan and cystoscopy. Gemcitabine/cisplatin was most commonly used with 20% using high-dose MVAC. Six (27%) reported doing midway staging with CT abdomen/pelvis and cystoscopy; 36% report staging after completion of chemo. Average time from last chemotherapy to cystectomy was 4-6 wks, with no patients being offered adjuvant chemotherapy postoperatively.

Conclusions: The majority of GU MO in Canada would offer NC. Stage, PS, renal function, and comorbidities were the biggest determinants of offering NC, while age played a lesser role. The number of overall referrals for NC, however, remains relatively low. We plan to survey urologists in Canada to determine if differences in attitudes about NC or barriers to referrals account for the low number of referrals.

No significant financial relationships to disclose.

Neuroprotective role of intermittent fasting in senescence-accelerated mice P8 (SAMP8)

Dietary interventions have been proposed as a way to increase lifespan and improve health. The senescence-accelerated prone 8 (SAMP8) mice have a shorter lifespan and show alterations in the central nervous system. Moreover, this mouse strain shows decreased sirtuin 1 protein expression and elevated expression of the acetylated targets NFkappaB and FoxO1, which are implicated in transcriptional control of key genes in cell proliferation and cell survival, in reference to control strain, SAMR1. After eight weeks of intermittent fasting, sirtuin 1 protein expression was recovered in SAMP8. This recovery was accompanied by a reduction in the two acetylated targets. Furthermore, SAMP8 showed a lower protein expression of BDNF and HSP70 while intermittent fasting re-established normal values. The activation of JNK and FoxO1 was also reduced in SAMP8 mice subjected to an IF regimen, compared with control SAMP8. Our findings provide new insights into the participation of sirtuin 1 in ageing and point to a potential novel application of this enzyme to prevent frailty due to ageing processes in the brain.

A review of the patterns of docetaxel use for hormone refractory prostate cancer (HRPC) at the Princess Margaret Hospital

e16161

Background: Docetaxel is standard of care for the treatment of HRPC, based on two large randomized clinical trials. The aim of this study was to determine if docetaxel use and effectiveness in routine clinical practice was similar to that seen in the TAX 327 randomized phase III clinical trial. Methods: A retrospective chart review was undertaken to assess patterns of docetaxel use for HRPC at our institution for the 2-year period since its approval for the first-line treatment of HRPC in 2005. Results: Eighty-eight patients, median age 71 and baseline PSA 107, received docetaxel in the first line setting. Main reasons for initiating docetaxel were rising PSA (90%) and progressive symptoms (71%). Eighteen percent of patients received docetaxel for rising PSA alone. A median of 7 cycles was administered. PSA response rates were 61%, time to response 1.5 months, and response duration 6.8 months. Disease progression was the most common reason for treatment discontinuation (36%). Main toxicities were fatigue (32%) and neuropathy (22%). Kaplan Meier survival analysis showed median duration of survival was 15.9 months (95% CI 12.4–20.5) from first drug use. 1-year survival was 0.63 (95% CI 0.52–0.72). Post-docetaxel, 36 patients received second-line treatment, mostly with mitoxantrone (89%). Second-line response rates were 22%, and median duration of response was 4 months. Conclusions: In routine clinical practice, docetaxel is a well-tolerated regimen for the treatment of HRPC. Response rates and toxicity profiles were comparable to the randomized trials. However, compared with the TAX 327 clinical trial, survival was slightly shorter than expected (15.9 vs. 18.9 months), possibly due to inclusion of patients with poorer performance status and comorbidities, who may be excluded from clinical trials. Second-line response rates were also comparable with previous reports.

No significant financial relationships to disclose.

Pre-clinical activity of the PARP inhibitor AZD2281 in human breast cancer cell lines and in combination with DNA damaging agents

Abstract #1038

Background: Deficiencies in DNA repair mechanisms have been associated with breast cancer. AZD2281, a potent, oral, PARP inhibitor has been shown to have clinical activity in patients with BRCA mutant breast cancers. Laboratory studies have suggested that non-BRCA mutant breast cancers may also be sensitive to PARP inhibition in tumors as a consequence of deficiencies in other homologous recombination (HR) repair components. Using a large panel of human breast cancer cell lines we tested the hypotheses that (1) there may be a subset of non-BRCA mutant breast cancers that are sensitive to single-agent AZD2281 and (2) AZD2281 would potentiate the cytotoxic effects of the DNA damaging agent cisplatin. Methods: 43 human cell lines representing known molecular subgroups of breast cancer (i.e. ER+, HER2 amplified, “triple-negative”), and 3 immortalized breast lines were treated in duplicate in adherent plates with AZD2281 using two-fold dilutions over 6 concentrations for 6 days. Dose response curves were generated using a cell count assay to calculate the IC50 of AZD2281. In addition, a subset of cell lines that grow under anchorage independent conditions were grown in triplicate in the presence and absence of 1 µM AZD2281 in soft agar for at least 3 weeks and growth inhibition was calculated as per cent of untreated control. Cell lines (both sensitive and resistant to single agent AZD2281) were also evaluated in combination with cisplatin in a cell count assay to assess the interaction between the two agents.&#x2028; Results: The majority of breast cancer cell lines evaluated in the short term 2-D growth assay did not show significant growth inhibition (IC50 &lt; 1 µM) following AZD2281 treatment, including a known BRCA mutant cell line, suggesting this assay may not be ideal for determining sensitivity to AZD2281. However, in the longer term anchorage independent clonogenic assay, approximately half of the cell lines evaluated demonstrated an IC50 &lt; 1 µM. Of note, the majority of the cell lines representing a “triple-negative” phenotype appeared sensitive to AZD2281 in this assay. In addition, pre-treatment with AZD2281 prior to cisplatin, potentiated the growth inhibition seen with cisplatin in both AZD2281 sensitive and resistant cell lines. Additional studies evaluating predictive markers other than BRCA status are ongoing. Conclusion: The PARP inhibitor AZD2281 has significant pre-clinical activity in human breast cancer cell lines. In a clonogenic assay, cell lines representing the “triple negative” subtype were especially sensitive to AZD2281 supporting clinical development in this population, regardless of BRCA status. In addition, these pre-clinical data support the hypothesis that PARP inhibition may potentiate the effects of chemotherapy induced DNA damage and provide further rationale for clinical development.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 1038.

Predictive factors associated with immunosuppressive agent use in ulcerative colitis: a case-control study

BACKGROUND

Some patients with ulcerative colitis (UC) require immunosuppressants as maintenance therapy.

AIM

To assess epidemiological, clinical and disease factors at diagnosis that predict immunosuppressant use in UC.

METHODS

All UC patients diagnosed between 1992 and 2005 and currently managed in the inflammatory bowel disease (IBD) clinic were included. Forty-three patients who currently or previously received azathioprine (AZA) or mercaptopurine (MP) for UC were compared with 130 controls. Charts were reviewed and logistic regression analyses were applied to identify factors associated with AZA or MP use.

RESULTS

In univariate model, seven factors at diagnosis correlated with AZA use: male gender [odds ratio (OR) 2.2]; left-sided or extensive colitis or pancolitis (OR 8.7-14.1); systemic steroid use within the first 6 months of diagnosis (OR 5.1); more than 10 bowel movements daily (OR 6.4); persistent or mostly blood in stool (OR 2.8); endoscopic proven moderate to severe disease (OR 7.2-12.0) and requirement of hospitalization (OR 2.7) on diagnosis. In multivariate model, the first three factors were shown to be statistically significant.

CONCLUSION

Male gender, initial presentation with severe and extensive disease clinically and endoscopically, requirement of hospitalization on diagnosis or systemic steroids within 6 months of diagnosis are predictive factors for immunosuppressant use in UC.

Influence of vaccination and surgery on HLA-DR expression in patients with upper aerodigestive tract cancer

Major surgery is associated with an increased risk of post-operative immunosuppression and infections. We investigated the influence of influenza vaccination on cell-mediated immune responses in cancer patients undergoing either surgical or conservative therapy. Forty patients with an upper aerodigestive tract tumour were allocated to either a surgical or non-surgical treatment course. Patients within each group were randomized to the vaccination or non-vaccination group. Vaccination was performed twice before surgery or conservative treatment. Human leucocyte antigen receptor (HLA-DR) expression on monocytes was analysed by flow cytometry. In the surgical patients, HLA-DR expression on day 1 after surgery decreased in both the vaccinated and non-vaccinated groups. Vaccinated non-surgical patients showed significantly increased HLA-DR expression levels compared with the non-vaccinated patients. This pilot study demonstrated that vaccination increased monocyte HLA-DR expression in conservatively-treated cancer patients whereas surgery abrogated this response. Vaccination before surgery, therefore, might not help to maintain immune reactivity after surgery.