A randomized study of KRAS-guided maintenance therapy with bevacizumab, erlotinib or metronomic capecitabine after first-line induction treatment of metastatic colorectal cancer: the Nordic ACT2 trial

BACKGROUND

Maintenance treatment (mt) with bevacizumab (bev) ± erlotinib (erlo) has modest effect after induction chemotherapy in metastatic colorectal cancer (mCRC). We hypothesized the efficacy of erlo to be dependent on KRAS mutational status and investigated this by exploring mt strategies with bev ± erlo and low-dose capecitabine (cap).

PATIENTS AND METHODS

Included patients had mCRC scheduled for first-line therapy, Eastern Cooperative Oncology Group (ECOG) 0-1 and no major comorbidities. Treatment with XELOX/FOLFOX or XELIRI/FOLFIRI + bev was given for 18 weeks. After induction, patients without progression were eligible for randomization to mt; KRAS wild-type (wt) patients were randomized to bev ± erlo (arms wt-BE, N = 36 versus wt-B, N = 35), KRAS mutated (mut) patients were randomized to bev or metronomic cap (arms mut-B, N = 34 versus mut-C, N = 33). Primary end point was progression-free survival (PFS) rate (PFSr) at 3 months after start of mt. A pooled analysis of KRAS wt patients from the previous ACT study was performed.

RESULTS

We included 233 patients. Median age was 64 years, 62% male, 68% ECOG 0, 52% with primary tumor in situ. A total of 138 patients started mt after randomization. PFSr was 64.7% versus 63.6% in wt-B versus wt-BE, P = 1.000; and 75% versus 66.7% in mut-B versus mut-C, P = 0.579, with no significant difference in median PFS and overall survival (OS). In the pooled cohort, median PFS was 3.7 months in wt-B (N = 64) and 5.7 months in wt-BE (N = 62) (hazard ratios 1.03, 95% confidence interval 0.70-1.50, P = 0.867). The frequency of any grade 3/4 toxicities during mt was: 28%/58%/18%/15% (wt-B/wt-BE/mut-B/mut-C).

CONCLUSIONS

Addition of erlo to bev as mt in KRAS wt mCRC did not significantly improve PFS or OS, but it did increase toxicity. KRAS status does not seem to influence the outcome of treatment with erlotinib. Metronomic cap warrants further investigation in mt strategies, given our explorative results.

CLINICALTRIALSGOV

NCT01229813.

Predictive and prognostic factors for treatment and survival in 305 patients with advanced gastrointestinal neuroendocrine carcinoma (WHO G3): the NORDIC NEC study

BACKGROUND

As studies on gastrointestinal neuroendocrine carcinoma (WHO G3) (GI-NEC) are limited, we reviewed clinical data to identify predictive and prognostic markers for advanced GI-NEC patients.

PATIENTS AND METHODS

Data from advanced GI-NEC patients diagnosed 2000-2009 were retrospectively registered at 12 Nordic hospitals.

RESULTS

The median survival was 11 months in 252 patients given palliative chemotherapy and 1 month in 53 patients receiving best supportive care (BSC) only. The response rate to first-line chemotherapy was 31% and 33% had stable disease. Ki-67<55% was by receiver operating characteristic analysis the best cut-off value concerning correlation to the response rate. Patients with Ki-67<55% had a lower response rate (15% versus 42%, P<0.001), but better survival than patients with Ki-67≥55% (14 versus 10 months, P<0.001). Platinum schedule did not affect the response rate or survival. The most important negative prognostic factors for survival were poor performance status (PS), primary colorectal tumors and elevated platelets or lactate dehydrogenase (LDH) levels.

CONCLUSIONS

Advanced GI-NEC patients should be considered for chemotherapy treatment without delay.PS, colorectal primary and elevated platelets and LDH levels were prognostic factors for survival. Patients with Ki-67<55% were less responsive to platinum-based chemotherapy, but had a longer survival. Our data indicate that it may not be correct to consider all GI-NEC as one single disease entity.

Biweekly cetuximab and irinotecan as second-line therapy to patients with platinium-resistant gastroesophageal cancer

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Background: There is no established 2nd line therapy for patients (pts) with advanced gastroesophageal (GE) cancer. In 2004, the Danish government initiated a national health programme for pts with advanced cancer. Non- proven therapy may be offered after approval by an expert panel appointed by the National Board of Health that subsequently finances the cost of treatment. This programme has had a major impact on the management of cancer pts in Denmark and has accelerated the introduction and implementation of new therapies. Inspired by the excellent results in colorectal cancer a combination of cetuximab and irinotecan (CetIri) was chosen for platinum-resistant GE cancer. While awaiting approval of a phase II protocol CetIri was offered at a single institution. We report our preliminary experience with biweekly CetIri as 2nd line therapy in pts with GE cancer. Methods: All pts had histologically confirmed GE cancer (adeno- or squamous cell carcinoma) and all pts had previously received first line platinum based therapy. Pts received CetIri (cetuximab 500 mg/m2and irinotecan 180 mg/m2day 1) every 2nd week until progression or unacceptable toxicity. Response rate was evaluated by the investigator according to RECIST every 8th week. Toxicity was prospectively evaluated according to NCIC-CTC 3.0. Results: From December 2007 to August 2008, 31 consecutive pts was treated with CetIri. Median age was 62 years (33–76). Median performance status was 1 (0–2). Localisation of primary was: Esophagus 10%, GE junction 64%, gastric 26%. Twenty-seven pts (87%) had adenocarcimona. Median number of cycles were 6 (1–21). Most important grade 2–4 toxicities were non-haematological toxicity as diarrhea (25%), nausea (21%) and vomiting (11%). Three pts (11%) had grade 3 leukopenia, 1 had febrile neutropenia. Two pts had PR. Median PFS was 3.2 months. Fourteen pts (45%) received at least 6 courses (3 month of therapy). After a median follow-up of 6 month 5 pts continue CetIri without sign of PD. Conclusions: Biweekly CetIri is a convenient and well-tolerated 2nd line regimen in pts with GE cancer. Predictive factors are needed to select which pts will benefit from therapy. A confirmatory phase II study is ongoing.

[Table: see text]

Phase I study of docetaxel, oxaliplatin, and capecitabine as first-line therapy to patients with advanced gastroesophageal cancer

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Background: Previously, epirubicin, cisplatin, and 5-FU (ECF) were often recommended as first line therapy to patients (pts) with advanced gastro-esophageal cancer (GE). If cisplatin is substituted by oxaliplatin (E) and 5-FU by capecitabine (X) this regimen can easily be administered with comparable efficacy and lower toxicity. In addition, recent studies have shown that efficacy can be improved by adding docetaxel (T) to CF. We therefore initiated a phase I trial of docetaxel, short-time infusion of oxaliplatin and continuously capecitabine (TEX) as first line therapy to establish the recommended dose for further therapy. Methods: Pts were enrolled in cohorts of 3 at each dose level ( Table ). All pts had non resectable histologically GE adenocarcinoma. No pts had received prior chemotherapy. Therapy was given day 1 with escalating doses of docetaxel (60 mg/m2to 75 mg/m2, as a 60 minutes infusion), capecitabine (1000 to1250 mg/m2/day continuously) and oxaliplatin (85 to 130 mg/m2 as a 30 minutes infusion). Cycles were repeated every 3 weeks for a maximum of 8 cycles. Toxicity was evaluated according to NCIC-CTC 3.0. DLT was evaluated after the first TEX cycle and defined as non-hematological toxicity grade ≥ 3, neutropenia grade 4 or febrile neutropenia more than 7 days. Results: From June 2007 to July 2008, 16 consecutive pts were treated with escalating doses of TEX. Median age was 59 years (43–74), median performance status was 1 (0–1). At dose level 5, two of 4 pts had DTL (1 pt had grade 3 vomiting and nausea and 1 pt had grade 3 nausea, vomiting and diarrhea). In addition 3 of 4 pts had neutropenia grade 4 without fever at dose level 5. Presently, 12 pts are still alive. Conclusions: First line taxotere, oxaliplatin and capecitabine every 3 weeks is easily administered in an out-patient setting but with substantial GI and haematological toxicity at dose level 5. An additional 6 pts will be included at dose level 4 to confirm tolerability at dose level 4. [Table: see text]

No significant financial relationships to disclose.

A phase II study of thalidomide and temozolomide in patients with brain metastases from malignant melanoma: lymphopenia correlates with response

Background:

Central nervous system (CNS) metastases develop in nearly half of patients with advanced melanoma and in 15–20% CNS is the first site of relapse. Median overall survival is short, ranging from two to four months, and one-year survival rate is only 10–15%. THA has been shown to have both anti-angiogenetic and immuno-modulating effects. TMZ is an oral alkylating agent with an excellent oral bioavailability and it is highly lipophillic with an ability to penetrate the blood–brain barrier. TMZ and THA in combination were tested in patients with brain metastases from malignant melanoma.

Methods:

Between June 2004 and February 2007 patients with measurable metastatic melanoma in progression and PS ≤ 1 received TMZ in a dose of 150 mg/m² qd for seven days, followed by seven days off therapy and THA in 200 mg qd, both orally administered. Concomitant treatment with steroids was allowed. PBMCs were collected from the last 14 consecutive patients for evaluation of immune parameters.

Results:

Forty screened patients were eligible and evaluable for response, and 39 were evaluable for toxicity. 25 patients had asymptomatic and 15 symptomatic brain metastases. The toxicity was primarily grade 1–2 with no grade 4 or treatment-related deaths. Four patients had thromboembolic events grade 3. One patient obtained a CR and five a PR in the CNS, while two had CR and four had PR outside CNS. Overall response rate was 17.5%. We found a significant positive correlation between lymphopenia and objective response.

Conclusions:

The combination treatment was well tolerated but with more frequent thromboembolic events compared to single drug TMZ or THA. The treatment demonstrated activity in CNS as well as outside CNS. The correlation between lymphopenia and objective response needs further investigation.