Phase I trial of cetuximab in combination with capecitabine, weekly irinotecan, and radiotherapy as neoadjuvant therapy for rectal cancer

Neoadjuvant therapy of cetuximab combined with chemoradiotherapy in rectal cancer: A single-arm meta-analysis of noncomparative clinical studies and randomized controlled trials

OBJECTIVE

Preoperative chemoradiotherapy combined with radical resection has reduced local recurrence rates in rectal cancer. Cetuximab shows improvement in rectal cancer treatment. But the role for neoadjuvant therapy of cetuximab combined with chenmoradiotherapy in rectal cancer remains unclear. The present study aimed to use meta-analytical techniques to assess its benefit and risk.

MATERIALS AND METHODS

We searched PubMed, the Cochrane Library, Embase to identify the correlational non-comparative clinical studies and randomized controlled trials (RCTs). The primary endpoints of interest were pathological complete response (pCR), complete response (CR), partial response (PR), stable disease, progressive disease (PD), R0-resection, R1-resection, and R2-resection. The secondary included any grade of toxicity.

RESULTS

Eleven investigations (9 noncomparative open-label cohort studies and 2 randomized controlled trials) involving 550 patients were ultimately included. The pooled estimates of pCR was 10% (95% confidence interval [CI]: 7%-13%, I2 = 55.9%). Simultaneously, only a small amount of patients achieved CR (11%, 95% CI: 7%-15%, I2 = 44.0%), which was consistent with pCR. Besides, R0 resection (93%, 95% CI: 90%-96%, I2 = 16.5%) seemed to be increased but need further exploration. The safety was also calculated, and most of the toxicities were moderate.

CONCLUSION

Neoadjuvant therapy of cetuximab combined with chemoradiotherapy could not improve pCR. The raise of R0-resection rate needed to be verified by more high-quality and well-designed RCTs. Meanwhile, the morbidity of toxicity was relatively mild and acceptable.

Combination of novel systemic agents and radiotherapy for solid tumors - Part II: An AIRO (Italian association of radiotherapy and clinical oncology) overview focused on treatment toxicity

Clinical development and use of novel systemic agents in combination with radiotherapy (RT) is at nowadays most advanced in the field of treatment of solid tumors. Although for many of these substances preclinical studies provide sufficient evidences on their principal capability to enhance radiation effects, the majority of them have not been investigated in even phase I clinical trials for safety in the context of RT. In clinical practice, unexpected acute and late side effects may emerge especially in combination with RT. As a matter of fact, despite combined modality treatment holds potential for enhancing the therapeutic ratio, some concerns are raised from the lack of high-quality clinical data to guide the care of patients who are treated with novel compounds in conjunction with RT. The aim of this review is to provide, from a radio-oncological point of view, an overview of the most advanced combined treatment concepts for solid tumors focusing on treatment toxicity.

Combination of novel systemic agents and radiotherapy for solid tumors - part I: An AIRO (Italian association of radiotherapy and clinical oncology) overview focused on treatment efficacy

Over the past century, technologic advances have promoted the evolution of radiation therapy into a precise treatment modality allowing for the maximal administration of dose to tumors while sparing normal tissues. In parallel with this technological maturation, the rapid expansion in understanding the basic biology and heterogeneity of cancer has led to the development of several compounds that target specific pathways. Many of them are in advanced steps of clinical development for combination treatments with radiotherapy, and can be incorporated into radiation oncology practice for a personalized approach to maximize the therapeutic gain. This review describes the rationale for combining novel agents with radiation, and provides an overview of the current landscape focused on treatment efficacy.

Therapeutic Antibodies in Cancer Therapy

The therapeutic arsenal in solid tumors comprises different anticancer strategies with diverse chemotherapeutic agents and a growing number of biological substances. Large clinical study-based chemotherapeutic protocols combined with biologicals have become an important component in (neo-) adjuvant therapy alongside surgery in solid cancers as well as radiation therapy in some instances. In recent years, monoclonal antibodies have entered the mainstream of cancer therapy. Their first use was as antagonists of oncogenic receptor tyrosine kinases, but today monoclonal antibodies have emerged as long-sought vehicles for the targeted delivery of potent chemotherapeutic agents and as powerful tools to manipulate anticancer immune responses. There is a growing number of FDA approved monoclonal antibodies and small molecules targeting specific types of cancer suggestive of the clinical relevance of this approach.Targeted cancer therapies , also referred to as personalized medicine, are being studied for use alone, in combination with other targeted therapies, and in combination with chemotherapy. The use of monoclonal antibodies in colorectal and gastric cancer for example have shown best outcome when combined with chemotherapy, even though single agent anti-EGFR antibodies seem to be active in particular setting of metastatic colorectal cancer patients. However, it is not well defined whether the addition of anti-VEGF - and anti-EGFR strategies to chemotherapy could improve outcome in those patients susceptible to colorectal cancer-related metastases resection. Among the most promising approaches to activating therapeutic antitumor immunity is the blockade of immune checkpoints, exemplified by the recently FDA-approved agent, Ipilimumab, an antibody that blocks the coinhibitory receptor CTLA-4. Capitalizing on the success of Ipilimumab, agents that target a second coinhibitory receptor, PD-1, or its ligand, PD-L1, are in clinical development. This section attempts to discuss recent progress of targeted agents and in tackling a more general target applicable to gastrointestinal cancer .

Treatment outcomes regarding the addition of targeted agents in the therapeutic portfolio for stage II-III rectal cancer undergoing neoadjuvant chemoradiation

Background

To evaluate the impact of targeted agents in stage II-III rectal cancer undergoing neoadjuvant concurrent chemoradiation therapy (CCRT).

Method

A retrospective study was performed in 124 consecutive patients with clinically T₃N_0-2M₀-staged rectal cancer incorporating targeted agents in CCRT.

Results

Pathologic complete response was detected in 34.2% (n=26) of bevacizumab+FOLFOX-treated patients (n=76), which was significantly higher (p=0.019, post-hoc statistical power =35.87%) than that (n=10, 20.8%) of the cetuximab+FOLFOX-treated patients (n=48). Patients receiving cetuximab+FOLFOX therapy tended to develop severe liver toxicity (91.7%, n=44 versus 17.1%, n=13, p<0.0001), as evaluated by morphologic grading of hepatic steatosis and sinusoidal dilatation in laparoscopy. In the 57 patients with morphologically severe liver toxicity, 36 (63.2%) retained a normal liver function; for the remaining 21 patients with an abnormal liver function, the abnormality was self-limited in 19 patients, whereas 2 cetuximab–treated patients progressed to hepatic failure and mortality. A subset analysis within bevacizumab+FOLFOX-treated patients with either wild-type (n=36) or mutant (n=40) K-ras status indicated K-ras status did not significantly influence the treatment outcomes.

Conclusions

The addition of bevacizumab instead of cetuximab to FOLFOX in the neoadjuvant settings for T₃N_0-2M₀-staged rectal cancer could induce a promising rate of pathologic complete response and lesser hepatotoxicity.

The Addition of Target Therapy to Neoadjuvant Chemoradiotherapy in Locally Advanced Rectal Cancer: A Review

Currently, neoadjuvant fluoropyrimidine-based chemoradiotherapy (CRT) is standard practice in the management of locally advanced rectal cancer (LARC). In the last decade there has been a lively interest in the improvement of clinical outcomes by modifying this standard regimen by the addition of further agents. We review combinations of targeted therapies and conventional CRT currently under investigation in LARC patients.

Pre-operative chemoradiotherapy using capecitabine and cetuximab followed by definitive surgery in patients with operable rectal cancer

BACKGROUND

Achieving a high rate of complete pathological response with pre-operative chemoradiotherapy in rectal cancer is an unmet need. We evaluated the efficacy and toxicity of the combination of cetuximab, capecitabine and radiation therapy in the pre-operative setting of localized rectal cancer.

PATIENTS AND METHODS

Patients with clinically staged T3, T4 or nodepositive rectal cancer were treated with concurrent capecitabine and radiotherapy with weekly cetuximab starting one week before the start of radiation. This was followed by total mesorectal excision within 6-8 weeks. All patients achieving R0 resection received adjuvant capecitabine for 6 cycles.

RESULTS

Fifteen patients were treated and all underwent surgery. Sphincter preservation was achieved in 11 patients (73.3%) and pathological complete response in two. With a median follow up of 48 months (range 8.4-57.5), 12 patients were relapse-free and 14 were alive with 4-year relapse free survival of 80%. Overall survival was 93%. Significant grade 3 and 4 toxicity was mainly cetuximab-induced skin reactions (33%), radiation-induced skin toxicity (13%) and diarrhea (20%).

CONCLUSIONS

Adding cetuximab to pre-operative concurrent capecitabine and radiotherapy provides modest efficacy with manageable toxicity.

Targeted agents in GI radiotherapy: Clinical efficacy and side effects

Approximately 50% of all patients with cancer receive radiotherapy (RT) at some point during their treatment. Despite the advent of modern imaging and advances in planning and delivering highly-conformal and precise RT, further dose escalation to improve clinical outcome is often limited by the potential side-effects to adjacent tissues. Addition of chemotherapy to radiotherapy (CRT) has led to significant clinical improvements in many gastrointestinal malignancies but at the expense of increased toxicity as most chemotherapy drugs lack specificity. Targeted agents modulate specific biological pathways and can potentially enhance RT efficacy. However, so far, the majority of clinical studies incorporating targeted agents into RT and CRT have produced disappointing results in gastrointestinal malignancies. Also, we lack validated biomarkers and methods for monitoring and predicting the efficacy of these agents when combined with RT/CRT. In the present article, we will review the most important targeted therapies, and examine the efficacy and toxicity of these agents when combined with RT/CRT in gastrointestinal malignancies. The shortcomings as well as future challenges and perspectives for the successful use of these compounds with RT/CRT in future trials will also be outlined.

miR-21 expression and clinical outcome in locally advanced pancreatic cancer: exploratory analysis of the pancreatic cancer Erbitux, radiotherapy and UFT (PERU) trial

BACKGROUND

Locally advanced pancreatic cancer (LAPC) is associated with high mortality, and biomarker-driven treatment approach is currently lacking. This study evaluated safety and efficacy of a combination approach of chemotherapy followed by chemo-radiotherapy (CRT) +/- cetuximab, and the prognostic role of miR-21 in patients with LAPC treated with a multimodality approach.

PATIENTS AND METHODS

This was a randomised phase II trial in which patients with inoperable LAPC were offered gemcitabine and capecitabine (GEM-CAP) for 16 weeks. Patients with stable disease or response after GEM-CAP were randomised to capecitabine or UFT plus radiotherapy (RT) (A), or capecitabine or UFT plus cetuximab plus RT (B). The primary outcome of the study was overall survival (OS). Clinical outcome was compared according to baseline circulating miR-21 levels.

RESULTS

17 patients were enrolled and treated with GEM-CAP, with 13 patients achieving disease control and being randomised to arms A (n:7) and B (n:6). After a median follow-up of 61.2 months, median progression free survival (PFS) was 10.4 months and 12.7 months, median OS was 15.8 months and 22.0 months in arms A and B respectively (p > 0.05). Patients with high baseline plasma miR-21 had worse PFS (3.5 vs. 12.7 months; p:0.032) and OS (5.1 vs 15.3 months; p:0.5) compared to patients with low miR-21. Circulating miR-21 levels reflected miR-21 expression within the tissues.

CONCLUSIONS

Addition of Cetuximab to CRT following induction chemotherapy did not improve survival. High miR-21 baseline plasma expression was associated with poor clinical outcome in LAPC patients treated with induction chemotherapy followed by chemo-radiotherapy.

[Preoperative chemoradiotherapy for rectal cancer: experience from one centre]

PURPOSE

In recent decades, the management of rectal cancer has been significantly improved by optimizing the surgical treatment with the total mesorectal excision and the development of neoadjuvant radiotherapy with or without chemotherapy. In this study, we investigated the impact of changes in practice over a period of 15 years in an expert centre.

PATIENTS AND METHODS

A monocentric study was conducted retrospectively on cT3-resectable T4 patients who received chemoradiotherapy for a locally advanced rectal adenocarcinoma between 1993 and 2008. We studied sphincter preservation, pathological complete response (ypT0), survival, and toxicities by different concomitant chemotherapy and treatment period.

RESULTS

Among the 179 patients who had a chemoradiotherapy, 56.4% were received concomitant 5-fluoro-uracil-leucovorin, 28.5% with concomitant capecitabine, and 15.1% with concomitant oxaliplatin and capecitabine. The average dose of radiotherapy was 45 Gy (25×1.8 Gy). Five-year disease-free survival was 74.3% and overall survival 68.8%. The rate of local recurrence and distant metastases were 6.1 and 23.6%. In multivariate analysis, concomitant chemotherapy oxaliplatin and capecitabine improved the pathological complete response rate (ypT0; capecitabine: 6%, 5-fluoro-uracil-leucovorin: 10.3%, capecitabine-oxaliplatin: 22.2%), but not significantly (P=0.12) and with more toxicities, and treatment interruptions. Sphincter preservation rate was not improved significantly during the study period (1993-2004 vs. 2005-2008), but disease-free survival improved from 72.2% up to 87.5% (P=0.03).

CONCLUSION

Our results are consistent with those published in the literature. Concomitant chemotherapy with 5-fluoro-uracil or capecitabine remains the standard scheme. Upfront chemotherapy, before chemoradiotherapy, should be investigated with regard to the predominance of metastasis.

Acute small-bowel toxicity during neoadjuvant combined radiochemotherapy in locally advanced rectal cancer: determination of optimal dose-volume cut-off value predicting grade 2-3 diarrhoea

Background

Current therapeutic standard for locally advanced rectal cancer is the neoadjuvant radiochemotherapy with total mesorectal excision. Diarrhoea is the main acute side effect, induced by the dose to the small-bowel, frequently leading to a treatment modification. Aim of this study was to analyse the differences between the irradiated small-bowel volumes and the occurrence of acute diarrhea during combined radiochemotherapy for rectal cancer.

Methods

45 patients treated with a neoadjuvant radiochemotherapy (three-field box 50.4 Gy; Cetuximab, Capecitabine, Irinotecan) for locally advanced rectal cancer within a prospective phase I/II study were evaluated. Based on the dose-volume histograms, the small-bowel volumes receiving doses of 5, 10 … 45 Gy (V5, V10 …V45) were calculated and compared with the prospectively documented small- bowel toxicities.

Results

There was a statistically significant difference between irradiated small-bowel volumes and the severity of therapy related diarrhoea. The strongest validity concerning the risk of developing a grade 2–3 diarrhoea was seen at a dose level of 5 Gy (V 5) with a small-bowel volume of 291.94 cc. Patients with V 5 > 291.94 cc had significantly more often grade 2–3 diarrhoea, than patients with V5 below this cut-off value (82% vs. 29%; p < 0.0001).

Conclusions

In the inverse treatment planning of rectal caner patients the small-bowel volume receiving 5 Gy should be limited to about 300 cc.

Locally advanced rectal cancer: the importance of a multidisciplinary approach

Rectal cancer accounts for a relevant part of colorectal cancer cases, with a mortality of 4-10/100000 per year. The development of locoregional recurrences and the occurrence of distant metastases both influences the prognosis of these patients. In the last two decades, new multimodality strategies have improved the prognosis of locally advanced rectal cancer with a significant reduction of local relapse and an increase in terms of overall survival. Radical surgery still remains the principal curative treatment and the introduction of total mesorectal excision has significantly achieved a reduction in terms of local recurrence rates. The employment of neoadjuvant treatment, delivered before surgery, also achieved an improved local control and an increased sphincter preservation rate in low-lying tumors, with an acceptable acute and late toxicity. This review describes the multidisciplinary management of rectal cancer, focusing on the effectiveness of neoadjuvant chemoradiotherapy and of post-operative adjuvant chemotherapy both in the standard combined modality treatment programs and in the ongoing research to improve these regimens.

Phase I/II study of neoadjuvant bevacizumab, erlotinib and 5-fluorouracil with concurrent external beam radiation therapy in locally advanced rectal cancer

BACKGROUND

To determine the maximal tolerated dose of erlotinib when added to 5-fluorouracil (5-FU) chemoradiation and bevacizumab and safety and efficacy of this combination in patients with locally advanced rectal cancer.

PATIENTS AND METHODS

Patients with Magnetic resonance imaging (MRI) or ultrasound defined T3 or T4 adenocarcinoma of the rectum and without evidence of metastatic disease were enrolled. Patients received infusional 5-FU 225 mg/M2/day continuously, along with bevacizumab 5 mg/kg days 14, 1, 15 and 29. Standard radiotherapy was administered to 50.4 Gy in 28 fractions. Erlotinib started at a dose of 50 mg orally daily and advanced by 50 mg increments in the subsequent cohort. Open total mesorectal excision was carried out 6-9 weeks following the completion of chemoradiation.

RESULTS

Thirty-two patients received one of three dose levels of erlotinib. Erlotinib dose level of 100 mg was determined to be the maximally tolerated dose. Thirty-one patients underwent resection of the primary tumor, one refused resection. Twenty-seven patients completed study therapy, all of whom underwent resection. At least one grade 3-4 toxicity occurred in 46.9% of patients. Grade 3-4 diarrhea occurred in 18.8%. The pathologic complete response (pCR) for all patients completing study therapy was 33%. With a median follow-up of 2.9 years, there are no documented local recurrences. Disease-free survival at 3 years is 75.5% (confidence interval: 55.1-87.6%).

CONCLUSIONS

Erlotinib added to infusional 5-FU, bevacizumab and radiation in patients with locally advanced rectal cancer is relatively well tolerated and associated with an encouraging pCR.

Locally advanced rectal cancer: new findings in anticancer therapy

SUMMARY Rectal cancer accounts for nearly a third of colorectal cancer cases, with a mortality of 4–10 cases per 100,000 per year, thus accounting for 9% of cancer deaths both in males and in females in western countries. Management of locally advanced rectal cancer has undergone and continues to undergo significant progress in the last two decades: in particular, new multimodality strategies have contributed to marked improvements in terms of reduction of both local and distant recurrence rates. This review focuses and summarizes the effectiveness of multimodality approaches in the standard treatment programs for locally advanced rectal cancer and also discusses the ongoing research to improve these regimens.

The status of targeted agents in the setting of neoadjuvant radiation therapy in locally advanced rectal cancers

Radiotherapy has a longstanding and well-defined role in the treatment of resectable rectal cancer to reduce the historically high risk of local recurrence. In more advanced borderline or unresectable cases, where the circumferential resection margin (CRM) is breached or threatened according to magnetic resonance imaging (MRI), despite optimized local multimodality treatment and the gains achieved by modern high quality total mesorectal excision (TME), at least half the patients fail to achieve sufficient downstaging with current schedules. Many do not achieve an R0 resection. In less locally advanced cases, even if local control is achieved, this confers only a small impact on distant metastases and a significant proportion of patients (30-40%) still subsequently develop metastatic disease. In fact, distant metastases have now become the predominant cause of failure in rectal cancer. Therefore, increasing the intensity and efficacy of chemotherapy and chemoradiotherapy by integrating additional cytotoxics and biologically targetted agents seems an appealing strategy to explore-with the aim of enhancing curative resection rates and improving distant control and survival. However, to date, we lack validated biomarkers for these biological agents apart from wild-type KRAS. For cetuximab, the appearance of an acneiform rash is associated with response, but low levels of magnesium appear more controversial. There are no molecular biomarkers for bevacizumab. Although some less invasive clinical markers have been proposed for bevacizumab, such as circulating endothelial cells (CECS), circulating levels of VEGF and the development of overt hypertension, these biomarkers have not been validated and are observed to emerge only after a trial of the agent. We also lack a simple method of ongoing monitoring of 'on target' effects of these biological agents, which could determine and pre-empt the development of resistance, prior to radiological and clinical assessessments or even molecular imaging. These shortcomings probably explain our current relative lack of success in the arena of combining these agents with chemoradiation.

Design and conduct of early-phase radiotherapy trials with targeted therapeutics: lessons from the PRAVO experience

New strategies to facilitate the improvement of physical and integrated biological optimization of high-precision treatment protocols are an important priority for modern radiation oncology. From a clinical perspective, as knowledge accumulates from molecular radiobiology, there is a complex and exciting opportunity to investigate novel approaches to rational patient treatment stratification based on actionable tumor targets, together with the appropriate design of next-generation early-phase radiotherapy trials utilizing targeted therapeutics, to formally evaluate relevant clinical and biomarker endpoints. A unique aspect in the development pathway of systemic agents with presumed radiosensitizing activity will also be the need for special attention on patient eligibility and the rigorous definition of radiation dose-volume relationships and potential dose-limiting toxicities. Based on recent experience from systematically investigating histone deacetylase inhibitors as radiosensitizing agents, from initial studies in preclinical tumor models through the conduct of a phase I clinical study to evaluate tumor activity of the targeted agent as well as patient safety and tumor response to the combined treatment modality, this communication will summarize principles relating to early clinical evaluation of combining radiotherapy and targeted therapeutics.

Effect of neoadjuvant cetuximab, capecitabine, and radiotherapy for locally advanced rectal cancer: results of a phase II study

PURPOSE

The aim of this study was to investigate the efficacy and safety of neoadjuvant cetuximab, capecitabine, and radiotherapy for patients with locally advanced rectal cancer.

METHODS

Sixty-three eligible patients were selectively enrolled in this study. Neoadjuvant treatment consisted of cetuximab and capecitabine for 6 weeks and radiotherapy for 5 weeks. Surgical resection was performed 6-8 weeks after the completion of neoadjuvant treatment. KRAS mutation statuses were analyzed retrospectively after the cetuximab treatment. All the patients underwent a standardized postoperative follow-up for at least 3 years.

RESULTS

A pathological complete response (pCR) was achieved in eight patients (12.7 %). Overall down-staging was found in 49 patients (77.8 %). The 3-year disease-free survival (DFS) rate and overall survival (OS) rate was 76.2 % and 81.0 %, respectively. The most common adverse events during neoadjuvant treatment were acneiform skin rash (82.5 %), radiodermatitis (46.0 %), and diarrhea (36.5 %). KRAS mutations were detected in 19 of 63 (31.2 %) tumors. The down-staging rate in patients with KRAS wild-type (WT) was significantly higher than patients with KRAS mutation (P = 0.020). There was no significant difference in the pCR rate, 3-year DFS rate or 3-year OS rate between KRAS WT patients and KRAS-mutated patients.

CONCLUSION

Neoadjuvant treatment with cetuximab and capecitabine-based chemoradiotherapy is safe and well tolerated. The pCR rate, 3-year DFS rate and OS rate are not superior to the rate of neoadjuvant chemoradiotherapy using two or more cytotoxic agents. The KRAS WT is highly associated with tumor down-staging to cetuximab plus capecitabine-based CRT in patients with LARC.

The role of capecitabine in locally advanced rectal cancer treatment: an update

Preoperative infusional 5-fluorouracil (5-FU) and concurrent radiation therapy (RT) followed by total mesorectal surgery is the current standard of care for locally advanced rectal cancer (LAR). When compared with postoperative 5-FU-based chemoradiation, this strategy is associated with significantly lower rates of local relapse, lower toxicity and better compliance. Capecitabine is a rationally designed oral prodrug that is converted into 5-FU by intracellular thymidine phosphorylase. Substitution of infusional 5-FU with capecitabine is an attractive option that provides a more convenient administration schedule and, possibly, increased efficacy. Indeed, incorporation of capecitabine in combined modality neoadjuvant therapy for LAR has been under intense investigation during the last 10 years. Phase I and II clinical trials showed that a regimen consisting of capecitabine 825mg/m(2) twice daily for 7 days/week continuous oral administration in combination with RT is an active and well tolerated regimen, thereby being the preferred concurrent regimen. The definitive demonstration that efficacy of capecitabine/RT is similar to 5-FU/RT has been provided by the NSABP-R-04 and the German Margit trials. One approach to improve outcomes in rectal cancer is to deliver a second RT-sensitizing drug with effective systemic activity. Oxaliplatin and irinotecan are therefore good candidates. However, two phase III trials demonstrated that incorporation of oxaliplatin to capecitabine with RT did not improve early outcomes and, by contrast, increased toxicity. Capecitabine has also been combined with irinotecan. This regimen showed encouraging results in phase I and II clinical trials, which led to an ongoing phase III clinical trial. New strategies with induction chemotherapy with or without chemoradiation prior to surgery are currently under investigation. Whether or not capecitabine has a role in this setting is being investigated in ongoing trials. Incorporation of agents directed towards new targets, such as anti-epidermal growth factor receptor (EGFR) antibodies or antiangiogenic agents, in combination preoperative regimens, is being hampered by results of early trials in which efficacy outcomes with cetuximab were poor and an excessive rate of surgical complications with bevacizumab was observed. The lack of improvements in efficacy with the addition of cetuximab or bevacizumab in the adjuvant treatment of colon cancer led to concerns about further development of these agents in rectal cancer. The role of capecitabine in the postoperative adjuvant setting is the aim of the ongoing Dutch SCRIPT trial. The prediction of response associated with capecitabine has been based on expression of thymidylate synthase and dihydropyrimidine dehydrogenase, as well as on gene expression arrays. All these procedures require further validation and should be considered as investigational. In conclusion, capecitabine can safely and effectively replace intravenous continuous infusion of 5-FU in the preoperative chemoradiation setting for rectal cancer management. The addition of other new antineoplastic agents to a fluoropyrimidine-based regimen remains investigational.

Progress in rectal cancer treatment

The dramatic improvement in local control of rectal cancer observed during the last decades is to be attributed to attention to surgical technique and to the introduction of neoadjuvant therapy regimens. Nevertheless, systemic relapse remains frequent and is currently insufficiently addressed. Intensification of neoadjuvant therapy by incorporating chemotherapy with or without targeted agents before the start of (chemo)radiation or during the waiting period to surgery may present an opportunity to improve overall survival. An increasing number of patients can nowadays undergo sphincter preserving surgery. In selected patients, local excision or even a "wait and see" approach may be feasible following active neoadjuvant therapy. Molecular and genetic biomarkers as well as innovative imaging techniques may in the future allow better selection of patients for this treatment option. Controversy persists concerning the selection of patients for adjuvant chemotherapy and/or targeted therapy after neoadjuvant regimens. The currently available evidence suggests that in complete pathological responders long-term outcome is excellent and adjuvant therapy may be omitted. The results of ongoing trials will help to establish the ideal tailored approach in resectable rectal cancer.

[Prognostic significance of changes of tumor epidermal growth factor receptor expression after neoadjuvant chemoradiation in patients with rectal adenocarcinoma]

PURPOSE

The aim of the present study was to examine the effect of neoadjuvant chemoradiation on tumor epidermal growth factor receptor (EGFR) expression in patients with locally advanced rectal adenocarcinoma.

PATIENTS AND METHODS

A total of 53 patients with rectal adenocarcinoma (clinical stages II and III) were studied. Neoadjuvant treatment consisted of 50.4 Gy/28 fractions external radiation with concomitant continuous 5-fluorouracil. Surgical resection was performed 4-6 weeks after the chemoradiation. EGFR expression in the pretreatment biopsies and in the resected specimens was assessed with immunohistochemistry.

RESULTS

Patients with an increase of EGFR expression during chemoradiation had significantly shorter disease-free survival (DFS; p = 0.003) and overall survival (OS; p = 0.005) compared to patients with either no change or decrease in EGFR expression. The 5-year DFS in patients with increased EGFR expression was only 29% compared to 61% in patients without an increase of EGFR expression. Similarly, the 5-year OS of the patients with increased EGFR expression was 29% compared to 66% in patients without an increase of EGFR expression. All recurrences in patients who had an increase of EGFR expression occurred within the first 2 years after the treatment. The increase in EGFR expression was the only significant predictor of DFS (p = 0.007) and OS (p = 0.04) using multivariate Cox regression analysis.

CONCLUSION

An increase of EGFR expression during chemoradiation may be associated with significantly shorter DFS and OS. The increase of EGFR could identify a population of patients in whom the effect of the treatment with anti-EGFR therapy should be studied.

Toward the non-surgical management of locally advanced rectal cancer

Neoadjuvant short-course radiotherapy and long-course chemoradiation (CRT) reduce local recurrence rates when compared to surgery alone and remain widely accepted as standard of care for patients with locally advanced rectal cancer. However, surgery is not without complications and a non-surgical approach in carefully selected patients warrants evaluation. A pathological complete response to CRT is associated with a significant improvement in survival and it has been suggested that a longer time interval between the completion of CRT and surgery increases tumor downstaging. Intensification of neoadjuvant treatment regimens to increase tumor downstaging has been evaluated in a number of clinical trials and more recently the introduction of neoadjuvant chemotherapy prior to CRT has demonstrated high rates of radiological tumor regression. Careful selection of patients using high-resolution MRI may allow a non-surgical approach in a subgroup of patients achieving a complete response to neoadjuvant therapies after an adequate time period. Clearly this needs prospective evaluation within a clinical trial setting, incorporating modern imaging techniques, and tissue biomarkers to allow accurate prediction and assessment of response.

The current state of targeted agents in rectal cancer

Targeted biologic agents have an established role in treating metastatic colorectal cancer (CRC), and the integration of targeted therapies into the treatment of CRC has resulted in significant improvements in outcomes. Rapidly growing insight into the molecular biology of CRC, as well as recent developments in gene sequencing and molecular diagnostics, has led to high expectations for the identification of molecular markers to be used in personalized treatment regimens. The mechanisms of action and toxicities of targeted therapies differ from those of traditional cytotoxic chemotherapy. Targeted therapy has raised new insight about the possibility of tailoring treatment to an individual's disease, the assessment of drug effectiveness and toxicity, and the economics of cancer care. This paper covers the last decade of clinical trials that have explored the toxicity and efficacy of targeted agents in locally advanced and metastatic CRC and how their role may benefit patients with rectal cancer. Future efforts should include prospective studies of these agents in biomarker-defined subpopulations, as well as studies of novel agents that target angiogenesis, tumor-stromal interaction, and the cell signaling pathways implicated in rectal cancer.

Multicenter randomized phase II clinical trial comparing neoadjuvant oxaliplatin, capecitabine, and preoperative radiotherapy with or without cetuximab followed by total mesorectal excision in patients with high-risk rectal cancer (EXPERT-C)

PURPOSE

To evaluate the addition of cetuximab to neoadjuvant chemotherapy before chemoradiotherapy in high-risk rectal cancer.

PATIENTS AND METHODS

Patients with operable magnetic resonance imaging-defined high-risk rectal cancer received four cycles of capecitabine/oxaliplatin (CAPOX) followed by capecitabine chemoradiotherapy, surgery, and adjuvant CAPOX (four cycles) or the same regimen plus weekly cetuximab (CAPOX+C). The primary end point was complete response (CR; pathologic CR or, in patients not undergoing surgery, radiologic CR) in patients with KRAS/BRAF wild-type tumors. Secondary end points were radiologic response (RR), progression-free survival (PFS), overall survival (OS), and safety in the wild-type and overall populations and a molecular biomarker analysis.

RESULTS

One hundred sixty-five eligible patients were randomly assigned. Ninety (60%) of 149 assessable tumors were KRAS or BRAF wild type (CAPOX, n = 44; CAPOX+C, n = 46), and in these patients, the addition of cetuximab did not improve the primary end point of CR (9% v 11%, respectively; P = 1.0; odds ratio, 1.22) or PFS (hazard ratio [HR], 0.65; P = .363). Cetuximab significantly improved RR (CAPOX v CAPOX+C: after chemotherapy, 51% v 71%, respectively; P = .038; after chemoradiation, 75% v 93%, respectively; P = .028) and OS (HR, 0.27; P = .034). Skin toxicity and diarrhea were more frequent in the CAPOX+C arm.

CONCLUSION

Cetuximab led to a significant increase in RR and OS in patients with KRAS/BRAF wild-type rectal cancer, but the primary end point of improved CR was not met.

Radiotherapy and "new" drugs-new side effects?

BACKGROUND AND PURPOSE

Targeted drugs have augmented the cancer treatment armamentarium. Based on the molecular specificity, it was initially believed that these drugs had significantly less side effects. However, currently it is accepted that all of these agents have their specific side effects. Based on the given multimodal approach, special emphasis has to be placed on putative interactions of conventional cytostatic drugs, targeted agents and other modalities. The interaction of targeted drugs with radiation harbours special risks, since the awareness for interactions and even synergistic toxicities is lacking. At present, only limited is data available regarding combinations of targeted drugs and radiotherapy. This review gives an overview on the current knowledge on such combined treatments.

MATERIALS AND METHODS

Using the following MESH headings and combinations of these terms pubmed database was searched: Radiotherapy AND cetuximab/trastuzumab/panitumumab/nimotuzumab, bevacizumab, sunitinib/sorafenib/lapatinib/gefitinib/erlotinib/sirolimus, thalidomide/lenalidomide as well as erythropoietin. For citation crosscheck the ISI web of science database was used employing the same search terms.

RESULTS

Several classes of targeted substances may be distinguished: Small molecules including kinase inhibitors and specific inhibitors, antibodies, and anti-angiogenic agents. Combination of these agents with radiotherapy may lead to specific toxicities or negatively influence the efficacy of RT. Though there is only little information on the interaction of molecular targeted radiation and radiotherapy in clinical settings, several critical incidents are reported.

CONCLUSIONS

The addition of molecular targeted drugs to conventional radiotherapy outside of approved regimens or clinical trials warrants a careful consideration especially when used in conjunction in hypo-fractionated regimens. Clinical trials are urgently needed in order to address the open question in regard to efficacy, early and late toxicity.

Locally advanced rectal cancer: a comparison of management strategies

Traditionally, there has been a high local recurrence rate in rectal cancer and 10-40% of patients require a permanent stoma. Both short-course preoperative radiotherapy (SCPRT) and long-course preoperative chemoradiation (CRT) are used to reduce the risk of local recurrence and enable a curative resection. Total mesorectal excision has reduced the rate of local recurrence (even without radiotherapy) to below 10%, but has highlighted a high risk of metastatic disease in 30-40% of patients. Current trials suggest that in resectable cancers, where the preoperative magnetic resonance imaging (MRI) suggests the circumferential resection margin (CRM) is not potentially involved, then SCPRT and CRT are equivalent in terms of outcomes such as local recurrence, disease-free survival (DFS) and overall survival (OS). For patients with more advanced disease, where the CRM is breached or threatened according to the MRI, the integration of more active chemotherapy and biological agents into chemoradiation is an attractive strategy because of the high risk of metastases. However, in none of the trials published in the last decade has chemoradiation impacted on DFS or OS. We examine the strategies of neoadjuvant, concurrent, consolidation (after chemoradiation and before surgery) and postoperative adjuvant chemotherapy with cytotoxic agents, and the integration of biological agents for future potential strategies of treatment. We also compare the trials and compare the different strategies of long-course preoperative radiotherapy and SCPRT; the intensification of preoperative radiation and chemoradiation with dose escalation of external beam radiotherapy, using brachytherapy, intra-operative radiotherapy, hyperfractionation, and various available techniques such as intensity-modulated radiotherapy. We recommend examining dose escalation of radiotherapy to the primary tumour where MRI predicts a threatened CRM. Of the potential treatment strategies involving cytotoxic agents, such as neoadjuvant, concurrent, consolidation and postoperative adjuvant chemotherapy, the most promising would appear to be consolidation chemotherapy following chemoradiation in locally advanced disease, and neoadjuvant chemotherapy in MRI-selected patients who do not require radiation. Improvement in the quality of surgery is also an important future goal.

Expression of Transketolase like gene 1 (TKTL1) predicts disease-free survival in patients with locally advanced rectal cancer receiving neoadjuvant chemoradiotherapy

Background

For patients with locally advanced rectal cancer (LARC) neoadjuvant chemoradiotherapy is recommended as standard therapy. So far, no predictive or prognostic molecular factors for patients undergoing multimodal treatment are established. Increased angiogenesis and altered tumour metabolism as adaption to hypoxic conditions in cancers play an important role in tumour progression and metastasis. Enhanced expression of Vascular-endothelial-growth-factor-receptor (VEGF-R) and Transketolase-like-1 (TKTL1) are related to hypoxic conditions in tumours. In search for potential prognostic molecular markers we investigated the expression of VEGFR-1, VEGFR-2 and TKTL1 in patients with LARC treated with neoadjuvant chemoradiotherapy and cetuximab.

Methods

Tumour and corresponding normal tissue from pre-therapeutic biopsies of 33 patients (m: 23, f: 10; median age: 61 years) with LARC treated in phase-I and II trials with neoadjuvant chemoradiotherapy (cetuximab, irinotecan, capecitabine in combination with radiotherapy) were analysed by quantitative PCR.

Results

Significantly higher expression of VEGFR-1/2 was found in tumour tissue in pre-treatment biopsies as well as in resected specimen after neoadjuvant chemoradiotherapy compared to corresponding normal tissue. High TKTL1 expression significantly correlated with disease free survival. None of the markers had influence on early response parameters such as tumour regression grading. There was no correlation of gene expression between the investigated markers.

Conclusion

High TKTL-1 expression correlates with poor prognosis in terms of 3 year disease-free survival in patients with LARC treated with intensified neoadjuvant chemoradiotherapy and may therefore serve as a molecular prognostic marker which should be further evaluated in randomised clinical trials.

The current landscape of locally advanced rectal cancer

Postoperative adjuvant chemoradiotherapy was recommended as the standard treatment for patients with rectal cancer because it reduces local recurrence. This paradigm shifted with the use of neoadjuvant chemoradiotherapy, which not only reduces local recurrence but also improves sphincter preservation and surgical outcomes. However, the treatment of rectal carcinoma remains complicated. The accuracy of tumor staging can be compromised depending on the imaging modality used. The addition of modern chemotherapeutics and biologics to 5-fluorouracil as radiation sensitizers is questionable. Oxaliplatin as a radiation sensitizer has minimal effects on the pathologic complete response, but improves the radiographical response at the expense of an increased risk of toxicities. The role of biologics in addition to radiation therapy continues to be explored. Attention has focused on improving diagnostic imaging, radiation oncology, and surgical techniques, treatment regimens, and on exploring a role of molecular markers for patients with rectal cancers. We review the pivotal trials that have led to the current treatment paradigm for locally advanced rectal cancer and discuss novel methodologies that are being developed for the treatment of this prevalent malignancy.

EGF61 polymorphism predicts complete pathologic response to cetuximab-based chemoradiation independent of KRAS status in locally advanced rectal cancer patients

BACKGROUND

Cetuximab has shown significant clinical activity in metastatic colon cancer. However, cetuximab-containing neoadjuvant chemoradiation has not been shown to improve tumor response in locally advanced rectal cancer patients in recent phase I/II trials. We evaluated functional germline polymorphisms of genes involved in epidermal growth factor receptor pathway, angiogenesis, antibody-dependent cell-mediated cytotoxicity, DNA repair, and drug metabolism, for their potential role as molecular predictors for clinical outcome in locally advanced rectal cancer patients treated with preoperative cetuximab-based chemoradiation.

METHODS

130 patients (74 men and 56 women) with locally advanced rectal cancer (4 with stage II, 109 with stage III, and 15 with stage IV, 2 unknown) who were enrolled in phase I/II clinical trials treated with cetuximab-based chemoradiation in European cancer centers were included. Genomic DNA was extracted from formalin-fixed paraffin-embedded tumor samples and genotyping was done by using PCR-RFLP assays. Fisher's exact test was used to examine associations between polymorphisms and complete pathologic response (pCR) that was determined by a modified Dworak classification system (grade III vs. grade IV: complete response).

RESULTS

Patients with the epidermal growth factor (EGF) 61 G/G genotype had pCR of 45% (5/11), compared with 21% (11/53) in patients heterozygous, and 2% (1/54) in patients homozygous for the A/A allele (P < 0.001). In addition, this association between EGF 61 G allele and pCR remained significant (P = 0.019) in the 59 patients with wild-type KRAS.

CONCLUSION

This study suggested EGF A+61G polymorphism to be a predictive marker for pCR, independent of KRAS mutation status, to cetuximab-based neoadjuvant chemoradiation of patients with locally advanced rectal cancer.

Impact of KRAS Mutations on Management of Colorectal Carcinoma

The epidermal growth factor receptor (EGFR) pathway is a therapeutic target in the management of colorectal cancer (CRC). EGFR antagonists are active in this disease; however, only a subset of patients respond to such therapy. A Kirsten ras sarcoma viral oncogene (KRAS) wild-type (WT) status of the tumor is necessary, but possibly not sufficient, for a response to anti-EGFR monoclonal antibody therapy. Mechanisms of primary resistance to such therapy in patients harboring KRAS WT tumors are discussed. Strategies to overcome resistance to anti-EGFR monoclonal antibody therapy, including novel agents and combinations of novel therapies, are explored. Also, the use of anti-EGFR monoclonal antibodies in the adjuvant and neoadjuvant setting is reviewed.

KRAS and BRAF mutations and PTEN expression do not predict efficacy of cetuximab-based chemoradiotherapy in locally advanced rectal cancer

PURPOSE

Mutations in KRAS and BRAF genes as well as the loss of expression of phosphatase and tensin homolog (PTEN) (deleted on chromosome 10) are associated with impaired activity of antibodies directed against epidermal growth factor receptor in patients with metastatic colorectal cancer. The predictive and prognostic value of the KRAS and BRAF point mutations as well as PTEN expression in patients with locally advanced rectal cancer (LARC) treated with cetuximab-based neoadjuvant chemoradiotherapy is unknown.

METHODS AND MATERIALS

We have conducted phase I and II trials of the combination of weekly administration of cetuximab and irinotecan and daily doses of capecitabine in conjunction with radiotherapy (45 Gy plus 5.4 Gy) in patients with LARC (stage uT3/4 or uN+). The status of KRAS and BRAF mutations was determined with direct sequencing, and PTEN expression status was determined with immunohistochemistry testing of diagnostic tumor biopsies. Tumor regression was evaluated by using standardized regression grading, and disease-free survival (DFS) was calculated according to the Kaplan-Meier method.

RESULTS

A total of 57 patients were available for analyses. A total of 31.6% of patients carried mutations in the KRAS genes. No BRAF mutations were found, while the loss of PTEN expression was observed in 9.6% of patients. Six patients achieved complete remission, and the 3-year DFS rate was 73%. No correlation was seen between tumor regression or DFS rate and a single marker or a combination of all markers.

CONCLUSIONS

In the present series, no BRAF mutation was detected. The presence of KRAS mutations and loss of PTEN expression were not associated with impaired response to cetuximab-based chemoradiotherapy and 3-year DFS.

Radiation, chemotherapy and biological therapy in the curative treatment of locally advanced rectal cancer

OBJECTIVE

To review the published evidence relating to the use of radiotherapy (RT), chemotherapy and biological therapy as adjuncts to surgery in the curative treatment of rectal cancer.

METHODS

Searches were carried out of the MEDLINE and CANCERLIT databases together with conference abstracts from key meetings including the American Society of Clinical Oncology Annual Meeting and Gastrointestinal Cancers Symposium and the ECCO/ESMO Multidisciplinary Congress.

RESULTS

RT reduces local pelvic recurrence when used as an adjunct to surgery, even when this is performed optimally by total mesorectal excision (TME). RT is usually given as short-course preoperative radiotherapy (SCPRT) followed by immediate surgery which produces no or very little downstaging or long-course concurrent chemoradiation (CRT) followed by a 6-8 week gap prior to surgery which produces significant downstaging. The prognostic importance of achieving a clear histological circumferential resection margin is now well recognised and pathological assessment of the quality of surgery can predict long-term outcomes. Internationally there is considerable heterogeneity in the staging modalities and criteria used in deciding which approach might be used, in the reporting of histological results and in RT parameters (time/dose/fractionation/volume). Attempts to increase the potency of CRT have included the addition of concurrent chemotherapeutic and biological agents to the standard fluoropyrimidine although there is little randomised data and none with regard to long-term survival outcomes. Neither SCPRT nor downstaging CRT have been shown to reduce the rate of subsequent distant metastatic relapse which remains a significant clinical problem. The potential additional benefit of neoadjuvant or adjuvant chemotherapy in addition to SCPRT or long-course CRT remains ill-defined. Late morbidity can include bowel and sexual dysfunction, pelvic fractures and second malignancies with considerably more being known in relation to SCPRT than long-course CRT.

CONCLUSIONS

Improvements in imaging, pathology and surgical technique combined with multimodality treatment using RT and chemotherapy are leading to continuing improvements in the long term outcome for patients with rectal cancer although much remains to be learnt regarding the optimum strategy for use of these in different clinical contexts and their relationship to long-term morbidity.

Cetuximab and chemoradiation for rectal cancer--is the water getting muddy?

The epidermal growth factor receptor (EGFR) inhibitor cetuximab has been successfully combined with radical radiotherapy in head and neck cancer. In colorectal cancer, increased response rates are achieved by cetuximab and panitumumab within standard chemotherapy schedules, but not in chemoradiation regimens. This review examines the clinical evidence and potential mechanisms for an interaction when EGFR inhibitors are added to fluoropyrimidine-based chemoradiation in rectal adenocarcinoma.

METHODS

This review was compiled by searching PubMed and Medline for English language articles published until 2009 with established search strategies, supplemented by hand searching of abstracts from the proceedings of relevant international meetings. The primary outcome measure was pathological complete response (pCR).

RESULTS

Only 13 publications and three presentations in abstract of 13 phase I/II trials of preoperative chemoradiation with cetuximab in rectal cancer were identified. A total of 316 patients were identified who received cetuximab in combination with radiotherapy and 5-fluorouracil or capecitabine preoperatively. One hundred and thirty eight of these patients received either additional irinotecan or oxaliplatin. One study with panitumumab with safety but no efficacy results was identified, and two studies with gefinitib. The pCR rate ranged from 0-20%. The overall pooled pCR for cetuximab based chemoradiation was 9.1% (29/316). The rate of G3/G4 gastrointestinal toxicity, in terms of diarrhoea, varied from 5-30%, with an overall pooled rate of 47/313 (15%).

DISCUSSION

Potential reasons for the disappointing results of EGFR inhibition with fluoropyrimidine-based preoperative chemoradiation include a less critical role of repopulation in rectal adenocarcinoma using a non-curative radiation dose; or antagonistic effects on 5FU-based chemoradiation and oxaliplatin, if some cells arrest in G1 or G2-M and fail to pass through S phase.

CONCLUSION

Cetuximab combined with fluoropyrimidine-based chemoradiation is not currently recommended. A better understanding of the mechanisms involved in combinations of chemotherapy and radiotherapy might allow more effective future scheduling of biological and chemical agents in combination with radiation.

Topoisomerase I expression correlates to response to neoadjuvant irinotecan-based chemoradiation in rectal cancer

Biomarkers may help predict the efficacy of neoadjuvant chemoradiation in patients with rectal cancer. We hypothesized that the expression of topoisomerase I (Topo I) and thymidylate synthase (TS) may help predict the treatment response in patients undergoing irinotecan and capecitabine-based chemoradiation. Patients with rectal cancer (cT3/4Nx or Tx/N+) received neoadjuvant chemoradiotherapy within clinical studies with irinotecan and capecitabine. Samples of normal and tumour tissues were collected before the start of the treatment and during surgical resection. Topo I and TS were measured using real-time PCR. The results of gene expression levels were compared between responders (defined as ypT0-2 ypN0) and nonresponders (ypT3-4 or ypN1/2). A total of 38 patients were analysed, 18 of them were responders. The biopsies of the untreated tumour tissue of responding patients showed a significant higher expression of Topo I compared with nonresponding patients (P = 0.015). Normal tissue did not show this difference (P = 0.126). During chemoradiation, the Topo I expression in tumour tissue of responders decreased significantly. TS did not show any differences between responders and nonresponders before treatment, but a significant decrease in the tumour tissue of responders was noted at the end of the treatment. Our data suggest that Topo I expression in rectal tumour mucosa might serve as a predictor of response to the neoadjuvant irinotecan-based chemoradiation, and hence might be a factor contributing to the development of individualized treatment.

Early and Long-Term Outcomes of Patients Undergoing Liver Resection and Diaphragm Excision for Advanced Colorectal Liver Metastases

INTRODUCTION

At present, liver resection offers the best long-term outcome and only chance for cure in patients with colorectal liver metastases. However, there are no large series that report the early and long-term outcomes of patients who require simultaneous diaphragm excision. This study was designed to investigate these patients.

PATIENTS AND METHODS

A total of 285 consecutive liver resections were performed over a 10-year period. Of these, 258 had liver resections alone and 27 underwent liver resection and simultaneous diaphragm excision. Data were collected prospectively and analysed retrospectively. Pre-operative assessment was standardised. The outcomes between the two groups were compared.

RESULT

There was no difference in age, hospital stay or intra-operative blood loss. The diaphragm was histologically involved in four out of 27 resections. As a result, the cancer involved resection margin incidence was greater in the liver resection and diaphragm excision group (14.8% versus 3.9%; P = 0.12). The median tumour size was also different between the two groups (60 mm versus 30 mm; P = 0.001). The liver and diaphragm resection group had a greater peri-operative complication rate (44.4% versus 21.3%; P = 0.02) and mortality (7.4% versus 1.6%; P = 0.25). Overall and disease-free survival was significantly worse in the group who underwent simultaneous diaphragm excision and liver resection (P = 0.04 and P = 0.005, respectively). Diaphragm invasion was found to be an independent predictor of poor overall outcome (P = 0.02).

CONCLUSION

Liver resection and simultaneous diaphragm excision have a greater incidence of peri-operative morbidity and mortality and a significantly worse long-term outcome compared with liver resection alone. However, these data suggest that liver resection in the presence of diaphragm invasion may still offer a favourable outcome compared with chemotherapy treatment alone. Therefore, we believe that diaphragm involvement by tumour should not be a contra-indication to hepatectomy.

Association of cetuximab with adverse pulmonary events in cancer patients: a comprehensive review

Compounds derived from biologic sources, or biologicals, are increasingly utilized as therapeutic agents in malignancy. Development of anti-cancer targeted therapies from biologics is increasingly being utilized. Cetuximab, a chimeric monoclonal antibody, is one such anti-cancer targeted therapeutic that has shown efficacy in quelling the rate of patient decline in colorectal, head/neck, and non-small cell lung cancer. However, due to the relatively recent addition of biologic compounds to the therapeutic arsenal, information related to adverse reactions is less well known than those seen in traditional chemotherapeutics. Dermatologic reactions have been demonstrated as the most frequent side effect cited during cetuximab therapy for malignancy; however, other effects may lead to greater morbidity. In general, pulmonary complications of therapeutics can lead to significant morbidity and mortality. The purpose of this review is to compile the various pulmonary side effects seen in patients treated with cetuximab for various malignancies, and to compare the incidence of these adverse reactions to standard therapies.

Early and long-term outcomes of patients undergoing liver resection and diaphragm excision for advanced colorectal liver metastases

INTRODUCTION

At present, liver resection offers the best long-term outcome and only chance for cure in patients with colorectal liver metastases. However, there are no large series that report the early and long-term outcomes of patients who require simultaneous diaphragm excision. This study was designed to investigate these patients.

PATIENTS AND METHODS

A total of 285 consecutive liver resections were performed over a 10-year period. Of these, 258 had liver resections alone and 27 underwent liver resection and simultaneous diaphragm excision. Data were collected prospectively and analysed retrospectively. Pre-operative assessment was standardised. The outcomes between the two groups were compared.

RESULTS

There was no difference in age, hospital stay or intra-operative blood loss. The diaphragm was histologically involved in four out of 27 resections. As a result, the cancer involved resection margin incidence was greater in the liver resection and diaphragm excision group (14.8% versus 3.9%; P = 0.12). The median tumour size was also different between the two groups (60 mm versus 30 mm; P = 0.001). The liver and diaphragm resection group had a greater peri-operative complication rate (44.4% versus 21.3%; P = 0.02) and mortality (7.4% versus 1.6%; P = 0.25). Overall and disease-free survival was significantly worse in the group who underwent simultaneous diaphragm excision and liver resection (P = 0.04 and P = 0.005, respectively). Diaphragm invasion was found to be an independent predictor of poor overall outcome (P = 0.02).

CONCLUSIONS

Liver resection and simultaneous diaphragm excision have a greater incidence of peri-operative morbidity and mortality and a significantly worse long-term outcome compared with liver resection alone. However, these data suggest that liver resection in the presence of diaphragm invasion may still offer a favourable outcome compared with chemotherapy treatment alone. Therefore, we believe that diaphragm involvement by tumour should not be a contra-indication to hepatectomy.

Molecular targeted treatment and radiation therapy for rectal cancer

BACKGROUND

EGFR (epidermal growth factor receptor) and VEGF (vascular endothelial growth factor) inhibitors confer clinical benefit in metastatic colorectal cancer when combined with chemotherapy. An emerging strategy to improve outcomes in rectal cancer is to integrate biologically active, targeted agents as triple therapy into chemoradiation protocols.

MATERIAL AND METHODS

Cetuximab and bevacizumab have now been incorporated into phase I-II studies of preoperative chemoradiation therapy (CRT) for rectal cancer. The rationale of these combinations, early efficacy and toxicity data, and possible molecular predictors for tumor response are reviewed. Computerized bibliographic searches of Pubmed were supplemented with hand searches of reference lists and abstracts of ASCO and ASTRO meetings.

RESULTS

The combination of cetuximab and CRT can be safely applied without dose compromises of the respective treatment components. Disappointingly low rates of pathologic complete remission have been noted in several phase II studies. The K-ras mutation status and the gene copy number of EGFR may predict tumor response. The toxicity pattern (radiation-induced enteritis, perforations) and surgical complications (wound healing, fistula, bleeding) observed in at least some of the clinical studies with bevacizumab and CRT warrant further investigations.

CONCLUSION

Longer follow-up (and, finally, randomized trials) is needed to draw any firm conclusions with respect to local and distant failure rates, and toxicity associated with these novel treatment approaches.

Recent advances relating to the clinical application of naked monoclonal antibodies in solid tumors

This review focuses on the recent advances in clinical data regarding antibody-based therapy in the management of solid tumors. We also discuss perspectives on antibody-based therapy in the future. Thorough understanding of the complex interactions between components of the immunological response has led to interest in the concept of immune-mediated therapy for solid tumors. Over the last few years, several humanized and chimeric monoclonal antibodies (MAbs) targeting human epidermal receptor 2 (HER2), epidermal growth factor receptor (EGFR), and vascular endothelial growth factor (VEGF) have been employed in treating solid tumors, including breast, colorectal, lung, head and neck, and gynecologic cancers. Trastuzumab, bevacizumab, cetuximab, and panitumumab are MAbs that are most widely used in clinical practice with acceptable rates of adverse events. Combination of MAbs with small-molecule inhibitors of the same pathway could potentially increase the efficacy and specificity of antibody-based treatment. Immune-mediated effects may be further exploited with the use of bivalent molecules.

mRNA expression of platelet-derived growth factor receptor-beta and C-KIT: correlation with pathologic response to cetuximab-based chemoradiotherapy in patients with rectal cancer

PURPOSE

Deviant expression of platelet-derived growth factor receptor-beta (PDGFRbeta) and c-kit was shown in patients with colorectal cancer. In the present study, mRNA expression of PDGFRbeta and c-kit in 33 patients with locally advanced rectal cancer undergoing preoperative chemoradiotherapy with cetuximab/capecitabine/irinotecan in correlation with the tumor regression rate was investigated.

METHODS AND MATERIALS

Pretherapeutic biopsy cores and tumor material from the resected specimens were collected in parallel with normal rectal mucosa. The expression levels of PDGFRbeta and c-kit were measured by quantitative polymerase chain reaction. Tumors were classified as good responders (tumor regression grade [TRG], 2-3) or poor responders (TRG, 0-1).

RESULTS

The TRG evaluation of the resected specimen was TRG 0-1 in 11 and TRG 2-3 in 22. The median normalized ratios in the pretreatment mucosa vs. tumor biopsy cores was as follows: PDGFRbeta ratio of 15.2 vs. 49.5 (p <0.0001) and c-kit ratio of 0.94 vs. 0.67 (p = 0.014). The same tendency was observed for the median PDGFRbeta ratios after chemoradiotherapy completion: 34.2 vs. 170.0 (p <0.0001). The PDGFRbeta and c-kit mRNA expression values in the pretreatment tumor biopsy cores were lower than the values in the resected specimens: PDGFRbeta ratio 49.5 vs. 170.0 (p = 0.0002) and c-kit ratio 0.67 vs. 1.1 (p = 0.0003). Nevertheless, no correlation was seen between the pretherapeutic PDGFRbeta and c-kit mRNA expression and the pathologic regression rate.

CONCLUSION

Cetuximab-based chemoradiotherapy increased PDGFRbeta levels even further compared with the pretreatment samples and deserves further investigation.