E. Bajetta

PI3KCA/PTEN deregulation contributes to impaired responses to cetuximab in metastatic colorectal cancer patients

BACKGROUNDnIt has been reported that KRAS mutations (and to a lesser extent KRAS mutations with the BRAF V600E mutation) negatively affect response to anti-epidermal growth factor receptor (EGFR) mAbs in metastatic colorectal cancer (mCRC) patients, while the biological impact of the EGFR pathway represented by PI3K/PTEN/AKT on anti-EGFR treatment is still not clear.nnnPATIENTS AND METHODSnWe analysed formalin-fixed samples from a cohort of 32 mCRC patients treated with cetuximab by means of EGFR immunohistochemistry, EGFR and PTEN FISH analysis, and KRAS, BRAF, PI3KCA, and PTEN genomic sequencing.nnnRESULTSnTen (31%) of 32 patients showed a partial response to cetuximab and 22 (69%) did not [nonresponder (NR)]. EGFR immunophenotype and FISH-based gene status did not predict an anti-EGFR mAb response, whereas KRAS mutations (24%) and PI3K pathway activation, by means of PI3KCA mutations (13%) or PTEN mutation (10%)/loss (13%), were significantly restricted to, respectively, 41% and 37% of NRs.nnnCONCLUSIONnThese findings suggested that KRAS mutations and PI3KCA/PTEN deregulation significantly correlate with resistance to cetuximab. In line with this, patients carrying KRAS mutations or with activated PI3K profiles can benefit from targeted treatments only by switching off molecules belonging to the downstream signalling of activated EGFR, such as mammalian target of rapamycin.

Phase II study of vinorelbine in patients with pretreated advanced ovarian cancer: activity in platinum-resistant disease.

PURPOSEnThe aim of the study was to evaluate the activity of vinorelbine (VNLB) in a population of advanced ovarian cancer patients, with particular attention to defining its role in platinum-resistant disease.nnnPATIENTS AND METHODSnThirty-three patients were recruited and treated with VNLB 25 mg/m2 intravenously (IV) weekly. the median age was 53 years, performance status 0 to 2, and number of previous chemotherapy regimens two (range, one to five). Twenty-four patients were platinum-resistant; the remaining nine either were platinum-sensitive (four cases) or had undetermined sensitivity (five cases).nnnRESULTSnThe mean delivered dose-intensity of VNLB was 67% of the planned level, because 60% of the cycles were delayed due to neutropenia or anemia. Four partial responses (PRs) and one complete response (CR) were observed, for an overall response rate of 15% (95% exact confidence interval, 5.1% to 31.9%). All the responses occurred in the subgroup of 24 platinum-resistant cases, in whom the response rate was 21% (95% exact confidence interval, 7.1% to 42.1%). Seven patients became stabilized on VNLB, and 27% of the cases showed a reduction in serum cancer antigen 125 (CA 125) levels. G3/G4 side effects consisted of neutropenia, anemia, and worsening of preexisting peripheral neuropathy. No treatment-related deaths occurred.nnnCONCLUSIONnVNLB led to a 21% response rate in the population of heavily pretreated and platinum-resistant ovarian cancer patients. Further studies of VNLB alone or in combination with taxanes are warranted in patients with less pretreatment.

Randomized multicenter Phase II trial of two different schedules of irinotecan combined with capecitabine as first-line treatment in metastatic colorectal carcinoma.

The aim of the current randomized Phase II study was to investigate the efficacy and safety of capecitabine combined with irinotecan as first‐line treatment in metastatic colorectal carcinoma (CRC).

Endocrinological and clinical evaluation of exemestane, a new steroidal aromatase inhibitor

The androstenedione derivative, exemestane (FCE 24304), is a new orally active irreversible aromatase inhibitor. Fifty-six post-menopausal advanced breast cancer patients entered this study to evaluate the activity of four low exemestane doses in reducing oestrogen levels. The drugs tolerability and clinical efficacy were also assessed. Exemestane was orally administered to four consecutive groups at daily doses of 25, 12.5, 5 and 2.5 mg, and the changes in oestrogen, gonadotrophins, sex-hormone binding globulin and dehydroepiandrosterone sulphate levels were evaluated. Drug selectivity was studied by measuring 17-hydroxycorticosteroid urinary levels. After 7 days of treatment, mean oestrone and oestradiol levels had decreased by respectively 64% and 65% (a decrease which was maintained over time); in the 2.5 mg group, oestrone sulphate levels also decreased by 74%. Gonadotrophin levels were significantly higher, whereas no changes in the other serum hormone levels or any interference with adrenal synthesis were detected. Treatment tolerability was satisfactory: nausea and dyspepsia were reported in 16% of patients. The overall objective response rate was 18%. In conclusion, exemestane is effective in reducing oestrogen levels at all of the tested doses and shows interesting clinical activity.

Doxifluridine and leucovorin: an oral treatment combination in advanced colorectal cancer.

PURPOSEnThis study was designed to test the activity and feasibility of an all-oral regimen of levo-leucovorin and doxifluridine (dFUR) in the treatment of advanced colorectal cancer and to establish whether the pharmacokinetics of dFUR and fluorouracil (FU) are affected by demographic and/or biologic parameters.nnnMATERIALS AND METHODSnOne hundred eight patients with histologically proven colorectal cancer received orally administered levo-leucovorin 25 mg followed 2 hours later by dFUR 1,200 mg/m2 on days 1 to 5, with the cycle being repeated every 10 days.nnnRESULTSnAmong 62 previously untreated patients, two complete responses (CRs) and 18 partial responses (PRs) were observed (overall response rate, 32%; 95% confidence interval, 21% to 45%). The median response duration was 4 months (range, 2 to 13) and the median survival time, 14 months. Among 46 pretreated patients, there were three CRs and three PRs (response rate, 13%; 95% confidence interval, 5% to 26%). In this group of patients, the median response duration was 4 months (range, 1 to 12) and the median survival time, 12 months. No toxic deaths were observed. The only World Health Organization (WHO) grade 3 to 4 side effect was diarrhea (32 patients).nnnCONCLUSIONnThis regimen is active in previously untreated colorectal cancer patients and combines good compliance with safety. Limited but definite efficacy was also detected in the patients previously treated with FU, which suggests incomplete cross-resistance between the two drugs. The pharmacokinetic results suggest that the conversion rate of dFUR to FU increases between days 1 and 5, but that FU levels remain low in comparison to those measured after classical FU therapy. Under the experimental conditions used in this study, the interpatient variability of pharmacokinetic parameters remains largely unexplained by the tested variables.

The minimal effective exemestane dose for endocrine activity in advanced breast cancer

Phase I studies have demonstrated that exemestane, an irreversible oral aromatase inhibitor, is able to suppress circulating oestrogen levels. In our previous experience, doses ranging from 2.5 to 25 mg induced a similar suppression of oestrogens. The aim of this study was to identify the minimum effective exemestane dose on the basis of endocrine activity. 20 evaluable postmenopausal advanced breast cancer patients were randomly given exemestane 0.5, 1, 2.5 or 5 mg, in double-blind conditions. Oestrone (E1), oestradiol (E2), oestrone sulphate (E1S), gonadotrophins, sex-hormone binding globulin and dehydroepiandrosterone sulphate serum levels were evaluated from the first day of treatment to the 7th, 14th, 28th and 56th day. Serum E1, E2 and E1S levels were suppressed by all doses starting from day 7; the degree of inhibition versus baseline was 25 up to 72% for E1, 30 up to 62% for E2 and 16 up to 52% for E1S, with higher doses achieving greater suppression; these changes were maintained over time. A significant increase in FSH and LH levels was observed for all doses. Treatment tolerability was satisfactory. The endocrine effects of exemestane appear to be dose related and 0.5 and 1 mg are ineffective for adequately suppressing circulating oestrogens.

Tumor response and estrogen suppression in breast cancer patients treated with aromatase inhibitors

BACKGROUNDnThe rationale for the hormonal treatment of breast cancer (BC) is based on depriving tumor cells of estrogenic stimulation. Aromatase inhibitors (Als) block the conversion of peripheral tissue androgens to estrogens with different levels of potency. In an attempt to investigate the relationship between tumor response and estrogen suppression, we reviewed the hormonal and clinical data of two previous studies with formestane (250 and 500 mg i.m. fortnightly) in advanced BC patients.nnnPATIENTS AND METHODSnTwo hundred four BC patients were selected on the basis of the availability of records concerning their plasma estrone (El) and estradiol (E2) levels assessed at scheduled times. The degree of estrogen suppression and the best clinical response of each patient during the trials were considered.nnnRESULTSnThere was a positive and significant (P < 0.05) correlation between baseline and post-formestane E1 and E2 levels, with a decrease in the levels of both hormones irrespective of any antitumor response. In particular, the degree of plasma estrogen suppression was similar in the patients who experienced a complete remission and those with progressive disease (PD).nnnCONCLUSIONSnThe plasma estrogen suppression induced by aromatase inhibition is not the only mechanism accounting for its clinical activity. Many clinical trials have demonstrated that all AIs induce a similar antitumor response regardless of their potency, and further investigations are warranted in order to improve our understanding as to why the patients with PD also show a significant plasma estrogen suppression. It is possible that intratumoral aromatase activity may be a marker for selecting the BC patients most likely to respond to AI treatment.

Randomized trial on adjuvant treatment with FOLFIRI followed by docetaxel and cisplatin versus 5-fluorouracil and folinic acid for radically resected gastric cancer

BACKGROUNDnSome trial have demonstrated a benefit of adjuvant fluoropirimidine with or without platinum compounds compared with surgery alone. ITACA-S study was designed to evaluate whether a sequential treatment of FOLFIRI [irinotecan plus 5-fluorouracil/folinic acid (5-FU/LV)] followed by docetaxel plus cisplatin improves disease-free survival in comparison with 5-FU/LV in patients with radically resected gastric cancer.nnnPATIENTS AND METHODSnPatients with resectable adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to either FOLFIRI (irinotecan 180 mg/m(2) day 1, LV 100 mg/m(2) as 2 h infusion and 5-FU 400 mg/m(2) as bolus, days 1 and 2 followed by 600 mg/m(2)/day as 22 h continuous infusion, q14 for four cycles) followed by docetaxel 75 mg/m(2) day 1, cisplatin 75 mg/m(2) day 1, q21 for three cycles (sequential arm) or De Gramont regimen (5-FU/LV arm).nnnRESULTSnFrom February 2005 to August 2009, 1106 patients were enrolled, and 1100 included in the analysis: 562 in the sequential arm and 538 in the 5-FU/LV arm. With a median follow-up of 57.4 months, 581 patients recurred or died (297 sequential arm and 284 5-FU/LV arm), and 483 died (243 and 240, respectively). No statistically significant difference was detected for both disease-free [hazard ratio (HR) 1.00; 95% confidence interval (CI): 0.85-1.17; P = 0.974] and overall survival (OS) (HR 0.98; 95% CI: 0.82-1.18; P = 0.865). Five-year disease-free and OS rates were 44.6% and 44.6%, 51.0% and 50.6% in the sequential and 5-FU/LV arm, respectively.nnnCONCLUSIONSnA more intensive regimen failed to show any benefit in disease-free and OS versus monotherapy.nnnCLINICAL TRIAL REGISTRATIONnClinicalTrials.gov Identifier: NCT01640782.BACKGROUNDnSome trial have demonstrated a benefit of adjuvant fluoropirimidine with or without platinum compounds compared with surgery alone. ITACA-S study was designed to evaluate whether a sequential treatment of FOLFIRI [irinotecan plus 5-fluorouracil/folinic acid (5-FU/LV)] followed by docetaxel plus cisplatin improves disease-free survival in comparison with 5-FU/LV in patients with radically resected gastric cancer.nnnPATIENTS AND METHODSnPatients with resectable adenocarcinoma of the stomach or gastroesophageal junction were randomly assigned to either FOLFIRI (irinotecan 180mg/m2 day 1, LV 100mg/m2 as 2h infusion and 5-FU 400mg/m2 as bolus, days 1 and 2 followed by 600mg/m2/day as 22h continuous infusion, q14 for four cycles) followed by docetaxel 75mg/m2 day 1, cisplatin 75mg/m2 day 1, q21 for three cycles (sequential arm) or De Gramont regimen (5-FU/LV arm).nnnRESULTSnFrom February 2005 to August 2009, 1106 patients were enrolled, and 1100 included in the analysis: 562 in the sequential arm and 538 in the 5-FU/LV arm. With a median follow-up of 57.4 months, 581 patients recurred or died (297 sequential arm and 284 5-FU/LV arm), and 483 died (243 and 240, respectively). No statistically significant difference was detected for both disease-free [hazard ratio (HR) 1.00; 95% confidence interval (CI): 0.85-1.17; P = 0.974] and overall survival (OS) (HR 0.98; 95% CI: 0.82-1.18; P = 0.865). Five-year disease-free and OS rates were 44.6% and 44.6%, 51.0% and 50.6% in the sequential and 5-FU/LV arm, respectively.nnnCONCLUSIONSnA more intensive regimen failed to show any benefit in disease-free and OS versus monotherapy.nnnCLINICAL TRIAL REGISTRATIONnClinicalTrials.gov Identifier: NCT01640782.

Uracil/ftorafur/leucovorin combined with irinotecan (TEGAFIRI) or oxaliplatin (TEGAFOX) as first-line treatment for metastatic colorectal cancer patients: results of randomised phase II study

This randomised phase II study evaluates the safety and efficacy profile of uracil/tegafur/leucovorin combined with irinotecan (TEGAFIRI) or with oxaliplatin (TEGAFOX). One hundred and forty-three patients with measurable, non-resectable metastatic colorectal cancer were randomised in a multicentre study to receive TEGAFIRI (UFT 250u2009mgu2009m−2u2009day days 1–14, LV 90u2009mgu2009day days 1–14, irinotecan 240u2009mgu2009m−2u2009day 1; q21) or TEGAFOX (UFT 250u2009mgu2009m−2u2009day days 1–14, LV 90u2009mgu2009day days 1–14, oxaliplatin 120u2009mgu2009m−2u2009day 1; q21). Among 143 randomised patients, 141 were analysed (68 received TEGAFIRI and 73 TEGAFOX). The main characteristics of the two arms were well balanced. The most common grade 3–4 treatment-related adverse events were neutropenia (13% of cases with TEGAFIRI; 1% in the TEGAFOX group). Diarrhoea was prevalent in the TEGAFIRI arm (16%) vs TEGAFOX (4%). Six complete remission (CR) and 19 partial remission (PR) were recorded in the TEGAFIRI arm (odds ratio (OR): 41.7; 95% confidence limit (CL), 29.1–55.1%), and six CR and 22 PR were recorded in the TEGAFOX group, (OR: 38.9; 95% CL, 27.6–51.1). At a median time follow-up of 17 months (intequartile (IQ) range 12–23), a median survival probability of 20 and 19 months was obtained in the TEGAFIRI and TEGAFOX groups, respectively. Median time to progression was 8 months for both groups. TEGAFIRI and TEGAFOX are both effective and tolerable first-line therapies in MCRC patients. The employment of UFT/LV given in doublet combination is interesting and the presented data appear comparable to equivalent infusion regimens described in the literature. The safety profile of the two combinations also allows an evaluation with other biological agents such as monoclonal antibodies.

Pathological features as predictors of recurrence after radical resection of gastric cancer

The aim of this study was to investigate the pattern and timing of recurrence and to determine associated risk factors after radical resection of gastric cancer including D2 dissection.