Neutropenia as a prognostic factor in metastatic colorectal cancer patients undergoing chemotherapy with first-line FOLFOX

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Background: FOLFOX combined with bevacizumab is established as standard first-line chemotherapy for metastatic colorectal cancer (MCRC), and neutropenia is one of the most common of its side effects. Neutropenia during chemotherapy has been reported to be a predictor of better survival in patients with several type of cancers, although there are no reports in MCRC. We aimed to assess whether neutropenia during chemotherapy could be a marker of improved survival of patients with MCRC. Methods: Patients with MCRC who received FOLFOX with or without bevacizumab as first-line chemotherapy were retrospectively analyzed to assess whether neutropenia during chemotherapy is associated with improved survival. Several background characteristics and chemotherapy features (grade of neutropenia, use of bevacizumab, use of irinotecan, reintroduction of oxaliplatin, and tumor progression) as time-varying covariates (TVCs) were analyzed as potential prognostic factors. Results: Of 153 patients, mild neutropenia (grade 1–2) occurred in 60 patients (39%) and severe neutropenia (grade 3–4) occurred in 46 patients (30%). The other 47 patients (31%) did not experience neutropenia. In 106 patients experiencing neutropenia, 66% of patients experienced their highest grade within 4 cycles. According to a multivariate Cox model with TVCs, hazard ratios of death were 0.55 (95% CI, 0.31–0.98; P = 0.044) for patients with mild neutropenia and 0.35 (95% CI, 0.18–0.66; P = 0.002) for those with severe neutropenia. If the analysis of neutropenia was limited to 4 cycles of FOLFOX, mild or severe neutropenia remained a significant prognostic factor according to survival analysis with TVCs. Conclusions: Both mild and severe neutropenia during chemotherapy are associated with improved survival in patients with MCRC. Prospective trials are required to assess whether dosing adjustments based on neutropenia may improve chemotherapy efficacy.

No significant financial relationships to disclose.

Development of an assay for KRAS mutation as a predictive marker for cetuximab in colorectal cancer

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Background: The activating KRAS mutation is an important predictive marker for anti-EGFR therapy against colorectal cancer (CRC), although valid assays using pathological specimens have not been yet established. We present a rapid, sensitive assay for KRAS genotyping using small biopsy specimens. Methods: We used Cycleave PCR to detect the KRAS mutation in CRC with a chimeric DNA-RNA-DNA probe labeled with fluorescent dye and quencher, with results obtained within 4 hours. Template DNA was extracted from formalin-fixed, paraffin-embedded specimens, which are surgically resected or biopsied in clinical practice. Results: To evaluate Cycleave PCR accuracy for detecting the KRAS mutation, we compared with results of reverse transcriptase-PCR-coupled direct sequencing (RT-PCR-DS) of metastatic lung tumor specimens from CRC patients. KRAS mutations were present in 40 (43%) of 94 patients, including 28 (30%) and 8 (9%) in codon 12 and codon 13 mutations, respectively. Concordant results between Cycleave PCR and RT-PCR-DS in KRAS codon 12 and 13 were found in 35/36 (97%) and 23/23 (100%), respectively. We also applied this method to surgical specimens in clinical practice. Although 8 from 73 patients (11%) could not be evaluated with Cycleave PCR, corresponding biopsy specimens could be used alternatively. Because biopsy specimens were fixed by formalin for a shorter period, fixation of surgical specimens for longer time may have contributed to PCR failure. Indeed, over- fixation by formalin impaired PCR amplification of KRAS in time-dependently. Furthermore, results of 4 randomly selected biopsy specimens using Cycleave PCR were consistent with those of surgical specimens. Conclusions: Cycleave PCR even using biopsy specimens is accurate, rapid, and useful to detect KRAS mutations in CRC patients. This study also called attention to specimen selection, as over-fixation by formalin may lead to failure of the gene examination due to template DNA fragmentation. This method can be applied to examine BRAF genotyping as well as KRAS. KRAS/BRAF genotyping by Cycleave PCR leads to individualized therapy using cetuximab for CRC patients.

No significant financial relationships to disclose.

Chemotherapy for patients with advanced gastric cancer with performance status 2

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Background: S-1 plus cisplatin is considered to be the standard chemotherapy for Japanese patients with advanced gastric cancer (AGC) according to the results of three phase III trials (JCOG9912/SPIRITS/TOP-002). However, since few patients with poor performance status (PS2) were included in these phase III trials (27 of 1317; 2%), the standard treatment of patients with PS2 has not been established yet. In also, the characteristics and prognosis of AGC patients with PS2 has not been reported in detail. Methods: We retrospectively analyzed 545 patients with AGC treated by chemotherapy during the period from January 2003 to June 2008. Patients characteristic and treatment results were compared between PS0–1 and PS2. Results: At the beginning of 1st-line chemotherapy, PS0–1/2/3–4 was 454/69/22 cases respectively. Patients with peritoneal/pleural dissemination was more common in PS2 than PS0–1 (75% vs. 43%, p<0.001). Patients with multiple metastatic places was more common in PS2 (62% vs. 43%; p=0.007). Fewer patients in PS2 were registered in clinical trial (1.4% vs. 25%, p<0.001). First-line chemotherapy using oral drug (S- 1/capecitabine) was significantly fewer in PS2 (43% vs. 75%, P<0.001). Median time to treatment failure was significantly shorter in PS2 (2.3 months vs. 4.2 months, p<0.001). Patients who could receive second-line chemotherapy were significantly fewer in PS2 (50% vs. 75%, p<0.001). With the median follow up time of 42 months, median survival time of patients with PS0–1 was 14.8 months (95% CI;13.1–16.5) and that of patients with PS2 was 6.1 months (4.3 to 7.4 months; hazard ratio for death 3.0: 95% CI2.3–4.0; p<0.001). Mortality rate within 30 days was higher in PS2 (3% vs. 0.2%; p<0.001). Conclusions: AGC patients with PS2 had not only had poor prognosis compared with PS0–1 but also had fewer chance of registration in the clinical trial, shorter time to treatment failure, and higher mortality rate within 30 days. Considering these different characteristics and treatment results of PS0–1 and PS2, clinical trial especially targeting AGC patients with PS2 is necessary to evaluate optimal chemotherapeutic regimens for PS2 patients.

No significant financial relationships to disclose.

Chemosensitivity of patients with recurrent esophageal cancer receiving perioperative chemotherapy

Perioperative chemotherapy (CT) and chemoradiotherapy are widely used for advanced esophageal cancer. We evaluated the chemosensitivity of patients displaying recurrent esophageal cancer after esophagectomy with perioperative CT. From the database at National Cancer Center Hospital in Tokyo, we extracted recurrent esophageal cancer cases after perioperative CT and evaluated the effectiveness of the first CT against the recurrent disease according to the duration between termination of the original perioperative CT and recurrence with treatment-free intervals (TFIs) <or=6 and >6 months. Systemic CT for their recurrent disease was performed for 30 esophageal cancer patients after perioperative CT. All patients received 5-fluorouracil and cisplatin as perioperative CT, with relapses occurring at TFIs <or=6 months in 11 patients (eight received platinum-containing regimens and three received docetaxel for their recurrent disease) and >6 months in 19 patients (all received platinum-containing regimens). The response rate of patients experiencing a recurrence at TFIs <or=6 and >6 months was 0 and 37% (P = 0.029), the median progression-free survival was 2.8 and 4.8 months (log-rank P = 0.001) and the median overall survival was 6.1 and 10.2 months (log-rank P = 0.012), respectively. Recurrence at the TFI <or=6 months could represent resistance to CT, so regimens may need to be altered depending on a patient's specific TFI.

Relationship of insulin-like growth factor-1 receptor and epidermal growth factor receptor expression to clinical outcomes in patients with colorectal cancer

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Background: Insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 have been reported to regulate tumor growth by interfering with apoptosis, cell proliferation, angiogenesis, and metastasis. However, the clinical significance of these molecules in colorectal cancer (CRC) remains undetermined. To gain further insight, we evaluated the prognostic implications of these biomarkers in patients with CRC treated with fluoropyrimidines or irinotecan. Methods: The study group comprised 91 patients who underwent surgery at National Cancer Center Hospital and subsequently received fluoropyrimidines as 1st-line chemotherapy for recurrent or residual tumors. The expressions of IGF-1R, EGFR, and HER2 in surgically removed specimens of primary lesions were analyzed immunohistochemically to determine the prognostic significance of these biomarkers. Results: IGF-1R expression (defined as >10% membranous staining) was found in 81 tumors (89%), EGFR in 77 (85%), and HER2 in 3 (3%). IGF-1R expression significantly correlated with EGFR expression (P=0.038). Overexpression (defined as >50% membranous staining) of IGF-1R was found in 48 tumors (53%), EGFR in 57 (63%), and HER2 in 2 (2%). Overexpression of IGF-1R significantly correlated with shorter survival from the start of 1st-line chemotherapy (P=0.032). Overexpression of EGFR was a significant predictive factor for a clinical response to fluoropyrimidines (P=0.037) and tended to correlate with TTP in patients given irinotecan as 2nd-line therapy (P=0.087). A multivariate analysis of potential prognostic factors showed that IGF-1R expression and worse performance status were independent predictors of poor outcomes ( Table ). Conclusions: IGF-1R and EGFR were highly positive in patients with CRC. Overexpression of IGF-1R predicts a poor outcome, and overexpression of EGFR predicts a good clinical response to fluoropyrimidines.

[Table: see text]

No significant financial relationships to disclose.

Impact of insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 expressions on outcomes of patients with gastric cancer

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Background: Insulin-like growth factor-1 receptor (IGF-1R), epidermal growth factor receptor (EGFR), and HER2 expressions have been reported to correlate with clinical outcomes in several solid tumors. However, the clinical significance of these biomarkers in gastric cancer (GC) remains unclear. Detailed exploratory evaluations are required to better understand their clinical implications. Methods: The study group comprised 87 patients who underwent gastrectomy at National Cancer Center Hospital and subsequently received chemotherapy for recurrent or residual tumor. Using immunohistochemical techniques, we analyzed the expressions of IGF-1R, EGFR, and HER2 in surgically removed tumor specimens to determine the prognostic significance of these biomarkers. Results: IGF-1R expression (defined as >10% membranous staining) was found in 67 tumors (77%), EGFR in 55 tumors (63%), and HER2 in 16 tumors (18%). IGF-1R expression correlated with EGFR expression (P=0.019) as well as with HER2 expression (P=0.001). A univariate analysis revealed that IGF-1R expression correlated with shorter survival (P=0.030). A multivariate analysis of potential prognostic factors showed that IGF-1R expression, worse performance status and pathological stage, and diffuse type tumor were independent predictors of poor outcomes ( Table ). Conclusions: IGF-1R expression in surgical GC specimens may be a predictor of poor outcomes in postoperative patients with GC. Our data suggest that anti-IGF-1R strategies may prove valuable in such patients.

[Table: see text]

No significant financial relationships to disclose.

[Paralytic ileus during treatment of acute promyelocytic leukemia with all-trans retinoic acid]

A 54-year-old man was referred to our hospital because of petechiae and pancytopenia. Bone marrow aspiration showed a normocellular marrow with 92.4% promyelocytes. PML/RAR alpha mRNA was detected by reverse transcription polymerase chain reaction. On the basis of above data, a diagnosis of acute promyelocytic leukemia (APL) was made, and treatment with all-trans retinoic acid (ATRA) at a dose of 60 mg/day was begun. Fourteen days after the start of treatment, the patient developed paralytic ileus, accompanied by hyperleukocytosis, high fever, renal dysfunction and elevation of the serum FDP level. There was no evidence of infection. At this time, retinoic acid syndrome was suspected, and therefore steroid pulse therapy was started, which led to an improvement of the symptoms within four days. This case suggests that ATRA may have an adverse effect on the small intestine, causing paralytic ileus.