Immunohistochemical analysis of tumour regression grade for rectal cancer after neoadjuvant chemoradiotherapy

AIM

Tumour regression grade (TRG) as defined by Rödel et al. has been used as an independent prognostic factor for rectal carcinoma after preoperative treatment by chemoradiotherapy (CRT). Determination of TRG 2 and 3, semiquantitatively defined as more or less than 50% tumour regression, respectively, does not appear to correlate with prognosis. The purpose of this study was to find an immunohistochemical pattern to permit improved stratification of intermediate responders defined by disease free (DFS) and overall survival (OS).

METHOD

Immunohistochemistry of EGFR (epidermal growth factor receptor), VEGF (vascular endothelial growth factor), CD133 antibody, p53 antibody and Ki67 antibody was evaluated using tissue microarrays (TMA) on post-treatment surgical specimens from 88 patients. CD133 expression was confirmed in the whole section when available.

RESULTS

At a median follow-up of 40 months, TRG was found to be an independent predictor of DFS (P = 0.05) and OS (P = 0.001) but no differences were found between TRG 2 and 3 in terms of DFS (P = 0.74) or OS (P = 0.41). The results of TMA showed an immunohistochemically poor prognostic profile for intermediate responders configured by negativity of CD133 expression. However, when examining CD133 expression in the whole section, there was an intermediate correlation with TMA and the prognostic significance was lost.

CONCLUSION

The results did not confirm the value of immunohistochemistry in predicting the prognosis of patients with rectal cancer following neoadjuvant chemoradiotherapy. This questions the accuracy of TMA in detecting CD133 expression in this setting.

Irinotecan-Cetuximab-Bevacizumab as a Salvage Treatment in Heavily Pretreated Metastatic Colorectal Cancer Patients: A Retrospective Observational Study

<i>Background:</i> The objective was to evaluate the efficacy of irinotecan-cetuximab-bevacizumab in combination as a salvage treatment for heavily pretreated metastatic colorectal cancer patients. <i>Methods:</i> A total of 39 patients resistant to both oxaliplatin and irinotecan were included in this retrospective study. Treatment consisted of irinotecan 180/m² every 14 days, weekly cetuximab standard dose and bevacizumab 5 mg/kg every 14 days. <i>Results:</i> Partial response was observed in 8 patients (20%), stable disease in 24 (61%) and progressive disease in 7 (18%). Overall response rate in KRAS wild type was 6/22 (27%) and in mutated KRAS it was 2/15 (13%). Median time to progression was 8 months (6.4–9.4) and median overall survival 12 months (10.1–13.8). Overall, grade 3–4 adverse events were observed in 24 patients (62%). <i>Conclusions:</i> This regimen is active and moderately well tolerated in heavily pretreated advanced colorectal patients. However, caution is advisable when interpreting these results, because they run against the findings of two large phase III trials.

Concordance of K-Ras status between colorectal cancer (CRC) primaries and related metastatic samples considering clinicopathological features

4053

Background: K-Ras mutations in CRC primaries may predict resistance to anti-epidermal growth factor receptor (EGFR) monoclonal antibodies, but we don´t know its behaviour in metastatic tissue. The aims of this study were: 1) Evaluate the grade of concordance of K-Ras status between primary and related metastatic samples 2) Establish a correlation between k-ras status and individual clinicopathological features Methods: K-ras mutations were retrospectively analysed in primary tumours of 124 patients and 138 related metastatic sites. The primary tumour site was colon in 87 patients and rectum in 37. Sites of metastases were liver (115 samples,83.3%) and lung (23 samples,16.7%). Some patients underwent surgery several times. We analyzed K-Ras point mutations in codons 12 and 13 by direct DNA sequencing from paraffin-embedded tumour and studied its relation with 13 clinicopathological features Results: K-Ras mutation was observed in 42(33.6%) primary tumours and in 52(39.1%) related metastatic sites, being the grade of concordance between primary and metastatic sites of 93% (95% CI: 97.5–88.3%). Discordance was observed in 9 (7%) patients: in 2, K-Ras status was wild type in metastatic site and expressed a mutational pattern in the primary tumour; vice versa, in 7, the mutation status was detected in the metastases meanwhile primary tumour was wild type. We also found statistically significative differences in mutation patterns regarding the site of the metastasic tissue: K-ras mutations were detected in 13 lung samples (61.9%) and in 39 liver samples (34.8%) (p=0.028). Of all the clinicopathological features analyzed we confirmed an increase of mutated K-ras status in tumours which had presented as perforation (p=0.044). No other relation with clinicopathological data was detected Conclusions: With this observational analysis, we confirm the high concordance (superior to 90%) between primary and related metastatic sites in terms of K-Ras status; for the first time, we have reported a higher mutational pattern in lung metastases than in liver disease, founds that may have important relevance regarding clinical/treatment decisions. For the realization of this study we received a grant from Amgen.

No significant financial relationships to disclose.

Cardiac toxicity: old and new issues in anti-cancer drugs

Although rare, cardiotoxicity is a significant complication of cancer treatment. The incidence and severity of cardiovascular side effects are dependent on the type of drugs used, dose and schedule employed, and age of patients, as well as the presence of coexisting cardiac diseases and previous mediastinal irradiation. Classically, anthracyclines are among one of the most active agents in oncology, but their use is often hampered by their cumulative dose-limiting cardiotoxicity. In the past decade, combination therapy with new drugs such as taxanes or anti- EGFR, and Her-2 therapy as a single agent have also resulted in unexpected cardiotoxicity. Cardiac damage can be secondary to an alteration of cardiac rhythm, changes in blood pressure and ischaemia, and can also alter the ability of the heart to contract and/or relax. The clinical spectrum of these toxicities can range from subclinical abnormalities to being catastrophic, life-threatening and sometimes fatal. Knowledge of this toxicity can aid clinicians to choose the optimal and least toxic regimen suitable for an individual patient. In this work we present an exhaustive review of the cardiovascular side effects associated to new anticancer drugs, from new formulations of anthracyclines to tyrosine kinase inhibitors and monoclonal antibodies.

Phase II study of a fixed dose-rate infusion of gemcitabine associated with erlotinib in advanced pancreatic carcinoma

15013

Background: The efficacy of gemcitabine in pancreatic cancer can be improved by its combination with erlotinib. Likewise, a fixed dose-rate infusion of gemcitabine seems to be superior to the conventional 30-minute infusion. Our objective was to evaluate the efficacy and toxicity of a fixed dose-rate infusion of gemcitabine associated with erlotinib in patients with advanced adenocarcinoma of the pancreas. Methods: From May 2005 to October 2006, 21 chemotherapy-naïve patients were included, median age 62 years (range 47 - 78), male/female 12/9. Five patients (24%) had locally advanced disease and 16 (76%) distant metastases. The Karnofsky score was 80–100 in 11 (52%), and 60–70 in 10 (48%). Treatment consisted of gemcitabine 1200 mg/m2 given as a 120-minute infusion on days 1, 8, 15, plus erlotinib 100 mg p.o daily. Cycles were repeated every 4 weeks. Results: A total of 80 cycles of chemotherapy were delivered with a median of 3.8 per patient (range 1- 8). There were five partial responses (24%, 95% CI: 8.4 - 47.6%), whereas seven patients had stable disease (33%) and 9 had a progression (43%). The median time to progression was 4 months. After a median follow-up of 6 months (1–14 months), the median overall survival has not been achieved. Toxicity was low. Grade 3- 4 WHO toxicities per patient were as follows: neutropenia in 5 (24%), thrombocytopenia in 1 (5%) and anaemia in 3 (14%). Grade 1–2 rash appeared in 8 (38%) and grade 3 in 3 (14%). Four patients (19%) had diarrhoea grade 1–2. Conclusions: These preliminary results suggest that a fixed dose-rate infusion of gemcitabine associated with erlotinib is active and well tolerated in patients with advanced pancreatic carcinoma.

No significant financial relationships to disclose.

Docetaxel and mitomycin as second-line treatment in advanced non-small cell lung cancer

PURPOSE

To evaluate the feasibility, toxicity and efficacy of the combination of docetaxel and mitomycin C as second-line chemotherapy in patients with advanced non-small cell lung cancer (NSCLC).

PATIENTS AND METHODS

Thirty-eight patients with histologically confirmed, locally advanced or metastatic NSCLC were included in this phase II trial. All patients had been previously treated with a platinum-based regimen. Treatment consisted of docetaxel (75 mg/m2) followed by mitomycin C (8 mg/m2) on day 1, every 21 days. Patients received a minimum of three courses unless progressive disease was detected.

RESULTS

A total of 190 courses of docetaxel-mitomycin C were administered (median five courses per patient). This combination was well tolerated with grade 3-4 toxicity experienced with the following frequency: neutropenia in five patients (13%), fatigue in four (11%), anaemia, thrombocytopenia, nausea/vomiting and peripheral neuropathy in one each (3%). Three of 38 patients had a partial response (8%, 95% confidence interval 2.6-21.6%), 14 patients (37%) experienced stabilization of disease and 21 (55%) had disease progression. Median time to progression was 3.6 months. Overall median survival was 10.4 months, with the 1-year actuarial survival rate being 35%.

CONCLUSIONS

The addition of mitomycin C to docetaxel as second-line therapy in NSCLC is well tolerated but does not seem to improve the response rate.