Immediate versus deferred initiation of androgen deprivation therapy in prostate cancer patients with PSA-only relapse. An observational follow-up study

BACKGROUND

The optimal timing to start androgen deprivation therapy (ADT) in prostate cancer patients with rising prostate-specific antigen (PSA) as the only sign of relapse is unknown.

METHODS

We identified men with prostate cancer in the Cancer of the Prostate Strategic Urologic Research Endeavour (CaPSURE) study who would have been eligible (⩽ cT3aN0M0, primary radical prostatectomy or radiotherapy, PSA relapse as the only evidence of recurrence) for a randomised trial comparing 'immediate' versus 'deferred' ADT initiation. We emulated such trial by assigning patients to the 'immediate' strategy if they initiated ADT within 3 months of PSA relapse and to the 'deferred' strategy if they initiated ADT when they presented with metastasis, symptoms or a short PSA doubling time. We censored patients when they deviated from the assigned strategy and adjusted for this censoring via inverse probability weighting.

RESULTS

Of 2096 eligible patients (median age 69, interquartile range 63-75 years), 88% were white, 35% had a Gleason score ⩾ 7, 69% were treated with radical prostatectomy and 31% received radiotherapy only as primary treatment. The mean time from primary treatment to PSA relapse was 37.4 (standard deviation [SD] 34.2) months. Mean follow-up from primary treatment was 91.4 (SD 48.4) months. The adjusted mortality hazard ratio for immediate versus deferred ADT was 0.91 (95% confidence interval (CI), 0.52-1.60), which would be translated into a similar 5-year survival (difference between groups: -2.0% (95% CI: -10.0 to 5.9%).

CONCLUSION

Our analysis suggests that prostate cancer patients undergoing immediate ADT initiation within three months after PSA-only relapse had similar survival to those who deferred ADT initiation within 3 months after clinical progression.

Multicenter phase II study of oxaliplatin and sorafenib in advanced gastric adenocarcinoma after failure of cisplatin and fluoropyrimidine treatment. A GEMCAD study

BACKGROUND

Cisplatin and fluoropyrimidine (CF) are standard first- line treatment in advanced gastric cancer, but no second-line treatment has yet been established. We present a phase II study in which we evaluated the efficacy and toxicity of the combination of Sorafenib (S), and Oxaliplatin as second-line therapy.

METHODS

Patients with progressive gastric adenocarcinoma after CF- first-line, ECOG 0-2, and measurable disease were included. The primary objective was PFS. Treatment doses were Oxaliplatin 130 mg/m²/3 weeks and Sorafenib 800 mg/bid/d.

RESULTS

We included 40 patients. CR was 2.5% and SD was 47.2%. Grade 3-4 toxic effects were neutropenia (9.8%), thrombocytopenia (7.3%), neurotoxicity (4.9%) and diarrhea (4.9%). Median PFS was 3 months (95%CI: 2.3-4.1) and median OS was 6.5 months (95% CI: 5.2-9.6). Time to progression (TTP) to first line therapy was a prognosis factor. Median OS was 9.7 months when time-to-progression during first-line chemotherapy was >6 months and 5.6 m when it was <6 months (p = 0.04).

CONCLUSIONS

Time-to-progression under a CF-based first-line therapy determines subgroups of GC patients with different prognosis. The combination of Oxaliplatin-Sorafenib in advanced GC patients previously treated with CF appears safe, but our results do not support the implementation of a phase III trial.

Aspirin for the prevention of colorectal cancer

Over 600,000 people worldwide die of colorectal cancer (CRC) annually, highlighting the importance of developing effective prevention strategies. Among proposed chemopreventive interventions, aspirin is perhaps the agent with the strongest body of evidence that supports wider spread use to significantly reduce the population burden of CRC. Several epidemiological studies, four randomized controlled trials (RCTs) of colorectal polyp recurrence, and RCTs in patients with hereditary colorectal cancer syndromes, have shown that aspirin reduces incidence of colorectal neoplasia. Recently, in a pooled analysis of five cardiovascular-prevention RCTs linked to cancer outcomes, daily aspirin use at any dose reduced the risk of CRC by 24% and of CRC-associated mortality by 35% after a delay of 8-10 years. In an expanded meta-analysis of 8 cardiovascular-prevention RCTs, daily aspirin use at any dose was associated with a 21% lower risk of all cancer death, including CRC, with benefit only apparent after 5 years. In this review, we will summarize human studies of aspirin in CRC prevention as well as discuss the safety profile and mechanism of aspirin in CRC prevention.

Cardiotoxicity of tyrosine-kinase-targeting drugs

The development of the so-called "targeted therapies", particularly those drugs that inhibit the activity of tyrosine kinases, has become a remarkable progress in the treatment of neoplastic diseases. The small molecule tyrosine kinase inhibitor (TKI) imatinib has revolutionized the treatment of chronic myeloid leukemia, and trastuzumab, the humanized monoclonal antibody against the ERBB2 receptor tyrosine kinase, has proved to have a high efficacy in 25% of breast cancers. On the basis of treatment success it is expected that targeted therapies will spread its use in the future. Recent data has shown that some of these therapies are associated with certain cardiotoxicity ranging from asymptomatic mild left ventricular dysfunction to congestive heart failure through different mechanisms. However, rates of cardiotoxicity associated with TKI are not well known mainly because clinical trials usually do not include predefined cardiac endpoints or the assessment of left ventricular function before and during treatment. In addition, it is especially difficult to diagnose heart failure in patients with some kinds of cancer who have many reasons to develop dyspnoea. Here we summarize what is known up to date about the cardiotoxicity of drugs targeting the tyrosine kinases. Being aware of the risk of using these drugs is particularly important to early detect and institute the appropriate treatment to prevent irreversible myocardial injury, especially when some neoplastic diseases, as haematological or breast cancers, can affect to young people with an estimated long-term survival.

Coexpression of matrix metalloproteinase-7 (MMP7) and phosphorylated insulin growth factor receptor I (pIGF-IR) as predictors of resistance to anti-EGFR therapy in advanced colorectal cancer (ACRC): A GEMCAD study

4063

Background: IGF-IR is supposed to have anti-apoptotic and mitogenic properties in colorectal cancer and by transactivation can promote EGFR phosphorylation. MMP-7 is produced by colorectal cancer cells and by degrading IGFBP-3 can activate IGF-IR. Methods: We retrospectively investigated the role of pIGF-IR immunoreactivity (IHC) (Rubini) and MMP-7 IHC in primary CRC or metastases, to predict response rate (RR), progression free survival (PFS) and overall survival (OS) in ACRC patients (pts) treated with either cetuximab or panitumumab as second or third line therapy. RAS mutational status of codons 12/13 was determined using quantitative PCR-based assay. CT scans were done every 1.5–2 months (m) until progressive disease. Results: A total of 99 pts with available tissue from 168 pts with ACRC treated with anti-EGFR therapy in 4 Spanish Institutions, were analysed for RAS mutational status, pIGF-1R and MMP-7. There were no major differences in RR (18.8 vs 16%), PFS [3.3 vs. 3.1 months (m)] and OS (7.7 vs. 7m) between the whole and selected cohort. Fifty-seven (57.6%) pts were male, the median age was 62 (range 34–79) years, the median number of previous chemotherapy lines was 2 (range 1–3) and PS was distributed as follow: PS0, 17 (17.2 %) pts; PS1, 66 (66.7%) pts and PS2, 16 (16.2%) pts. Expression of MMP-7 and pIGF-1R were observed in 48 (48.5%) and 52 (52.5%) pts respectively. Co-expression of MMP-7 and pIGF-1R [Double Positive (DP)] was observed in 26 (26.3 %) pts and in 16 (24%) out of 66 RAS wild-type (WTRAS) pts. There was no association between RAS mutational status and DP (p=0.52). DP progressed more than non-DP pts both in the overall sample (73 vs. 43%, p=0.028) and in WTRAS pts (75 vs. 32%, p=0.011). In the subset of WTRAS pts, DP pts also have a poorer OS: 6.4 (95% CI 5.8–7.1) m vs. 8.6 (95%CI 6.0–11.3) m (p=0.005), and a trend for worse PFS 2.7 vs 4.0 m (p=0.11). Conclusions: Co-expression of pIGF-1R and MMP7 is associated with resistance to anti- EGFR therapy in WTRAS pts. Our study suggests that pts with WTRAS and DP could be a target population to assay new anti-IGF-1R compounds.

No significant financial relationships to disclose.

EGFR polymorphism and KRAS mutational status as predictors of resistance to anti-EGFR therapy in advanced colorectal cancer (ACRC): A GEMCAD study

4060

Background: Single nucleotide polymorphism (SNP) in codon R497K of EGFR by reducing EGFR activity has been associated to resistance to anti-EGFR monoclonal antibodies in ACRC (Carcereny, ASCO2008). Methods: We retrospectively investigated the role of EGFR R497K and KRAS mutational status in primary CRC or metastases, in predicting response rate (RR), progression free survival (PFS) and overall survival (OS) of cetuximab or panitumumab in second or third line therapy in patients (pts) with ACRC. EGFR R497K was detected by real-time PCR using the TaqMan technology and KRAS mutation status in codons 12/13 was determined by sequencing. CT scans were done every 6–8 weeks (w) until progressive disease. Results: A total of 117 pts with available tissue out of 168 pts treated with anti-EGFR therapy in 6 Spanish Institutions, were analysed for EGFR R497K and KRAS mutational status. There were no differences in RR (18.8 vs.16.8%), PFS (13.2 vs. 12 w) and OS (31 vs. 28 w) between the whole and the selected cohort. We found no significant differences on RR (9/59;15.2 vs. 9/52; 17.3%), PFS (13.5 vs. 13.2 w) and OS (33 vs. 26.8 w) according to EGFR R497K (GG vs. GA/AA). Pts with wild-type (WT) KRAS had better response (20.7% vs. 8.1%;p=0.07) and PFS (14.4 vs. 11.7 w; p=0.006) compared with mutant KRAS. Interestingly, a significant increment on RR (30 vs. 0%, p=0.003), PFS (14.4 vs. 7.4 w, p=0.002) and OS (34.1 vs. 20 w, p=0.03) was observed only in those patients with WT KRAS and >1x upper limit of normal (ULN) lactate dehydrogenase (LDH) levels compared with mutant KRAS, but these differences were not found in pts with WT KRAS and <1xULN levels of LDH: [RR (14 vs. 14%, p=NS), PFS (14.4 vs. 13.1 w, p=NS) and OS (31 vs. 31 w; p=NS)]. Conclusions: EGFR R497K is not a predictive marker of efficacy to EGFR-inhibitors. Our study suggest that pts with WT KRAS and >1xULN levels of LDH, have major benefit to anti-EGFR therapy in second-third line therapy.

No significant financial relationships to disclose.

Correlation of serum interleukin-6 (IL-6) levels with immunohistochemical p65/nuclear factor-κB (NF-κB) expression and prediction of the clinical outcome of hormone-independent prostate cancer patients (HIPC) treated with docetaxel (D)

5075

Background: We have recently reported that NF-κB/IL-6 was linked to D response in human prostate cancer cells. In this study we investigated the clinical significance of IL-6 serum levels in HIPC pts treated with D and the correlation between serum IL-6 levels and p65/NF-κB tissue expression. Methods: Pts with HIPC treated with D were prospectively tested for IL-6 levels by ELISA before chemotherapy. In patients with available specimens of hormone-independent tumor p65/NF-κB was determined by immunohistochemistry. PSA response to D, time to progression and survival were analyzed. Results: Sixty pts were included. Median follow-up time was 29.3 (5.3–55.47) months. Median time to D progression was 4.2 (0,6–15.1) months and median survival was 10.1 (1.6- 47.1) months. Median baseline IL-6 were 16 pg/ml (range 0–156). Pts that responded to D had median IL-6 of 15.1±3.9 pg/ml and patients that did not respond had median IL-6 of 34.7±6.5 (p=0.009). IL-6 correlated with the number of bone metastasis (r=0.39, p=0.002), LDH levels (r=0.53, p<0.0001) and inversely with time to PSA progression (r=-0.65, p<0.0001) and survival (r=-0.61, p<0.0001). In the multivariate analysis IL-6 were an independent prognostic factor for time to PSA progression HR 1.026 (CI95% 1.013–1.046) and survival IL-6 levels HR 1.022 (CI 95% 1.006- 1.038, p=0.008). HIPC tissue samples from 12 pts were assessed for p65/NF-κB expression. All tissue samples showed cytoplasmatic and nuclear staining. Median percentage of nuclear p65/NF-κB stained cells was 15% (range 5–45%). P65/NF-κB nuclear staining showed correlation with serum IL-6 levels (r=0.719, p=0.009). Patients with low serum IL-6 levels (= 16 pg/ml) had a median % of nuclear p65/NF-κB staining of 5.4±2.5% and patients with high IL-6 levels had a median % of nuclear p65/NF-κB staining of 30.2±4.9% (p=0.001). Conclusions: High IL-6 serum levels were associated to a worse survival in HIPC pts treated with D. Our data suggest that the determination of serum IL-6 levels may serve as a surrogate marker of NF-κB activity in hormone-independent prostate cancer tumor and may be useful to select patients for NF-κB targeted therapy.

No significant financial relationships to disclose.

Serum matrilysin (MMP7) levels are associated with progression, in curatively resected colorectal cancer (CRC) patients

4124

Background: Matrilysin (MMP7) has been shown to be over-expressed in CRC, specially in liver metastases. Additionally MMP7 over-expression in primary tumor, predict metastatic potential in early-stage disease (Gut 12:1751;2005). As the activated pro-domain, could be detected in serum by ELISA method, we search if it could also identify a subgroup of non-metastatic CRC patients with a higher risk of relapse. Methods: Serum MMP7 (S-MMP7) was measured by commercially available ELISA, in 92 healthy controls and 175 consecutive patients before undergoing laparoscopy-assisted or open curative resection for CRC, between July 2003 to December 2004. Clinic- pathologic variables were tested for their effect on disease-free survival (DFS) in univariate and multivariate Cox regression analysis. Results: S-MMP7 levels were significantly higher in CRC patients than in controls (p=0.02). Mean age in CRC patients was 71 years (range 31–90). Median nodal retrieval was 14 (range 0–47). The median S-MMP7 (4.9 ng/ml) was chosen for cut-off value. After a median follow- up of 26 months, the rate of DFS was 72%. Univariate analysis identified high S-MMP7 levels, CEA concentration, age, extent of primary tumor and lymph-node metastases as variables associated with DFS. Multivariate analysis identified lymph-node metastases (OR.1,88, p=0.046) and S-MMP7 (OR.1,103, p=0.039) as independent prognostics factors. Conclusions: With a short follow-up, S-MMP7 levels predict recurrence in curatively resected CRC. As a subset of these patients could be managed with secondary liver resection, S-MMP7 determination would be particularly warranted for more intensive surveillance strategies.

No significant financial relationships to disclose.

Protein S-100β serum levels predicts clinical outcome of high-risk melanoma patients treated with high-dose adjuvant interferon alfa2b

8543

Background: S-100β serum levels have been shown to be useful to monitor response to therapy in metastatic melanoma patients. We have recently reported that S-100β levels could also be useful in the adjuvant context. In this study we analyze the clinical relevance of S-100β serum levels in an homogeneuos stage IIB-III group of patients treated with high-dose interferon. Methods: Patients with melanoma diagnosis were prospectively tested for serum S-100β protein by luminoimmunometric assay (LIA) before starting interferon (baseline) and every 3 months thereafter (on.therapy), until treatment was completed. Median time to progression and overall survival were assessed. Multivariate analysis using the Cox proportional hazards model with covariable dependent on time was perfomed since S-100β under therapy changes during time. Results: Ninety-seven patients were included. Median follow-up was 62.9 months (range 32.7–87.4). Median baseline S-100β levels were 0.06μg/l (range 0.06–0.53). S-100 was considered high (=0.15 μg/l) in 20.6% of the patients. High baseline S-100β levels were associated with positive lymph-node status (p=0.02). High S-100β levels (while on therapy) showed relation with positive lymph-node status (p=0.014), number of positive lymph-nodes (p=0.01), macroscopic lymph-node involvement (p=0.002) and second melanoma diagnosis at study entry (p=0.001). By univariate analysis, high baseline S-100β levels were associated with disease free survival (DFS) (p=0.004) and overall survival (OS) (p=0.0007). Similarly, high on therapy S-100β levels were associated with DFS (p<0.0001) and OS (p<0.0001). In the multivariate analysis, high on therapy S-100β levels (HR 1.029, CI95% 1.015–1.042; p<0.0001) was an independent prognostic factor for DFS. High on therapy S-100β levels (HR 1.017, CI 95% 1.10–1.026; p<0.0001) and high baseline S-100β levels (HR 3.31, CI 95% 1.10–9.89; p=0.032) were independent prognostic factors for OS. Conclusions: These results provide novel evidence of the clinical usefulness of serum S-100β levels determination for monitoring the clinical outcome of high-risk melanoma patients treated with adjuvant therapy.

No significant financial relationships to disclose.