S-1 and oxaliplatin (SOX) plus bevacizumab versus mFOLFOX6 plus bevacizumab as first-line treatment for patients with metastatic colorectal cancer: updated overall survival analyses of the open-label, non-inferiority, randomised phase III: SOFT study

Detailed analysis of metastatic colorectal cancer patients who developed cardiotoxicity on another fluoropyrimidine and switched to S-1 treatment (subgroup analysis of the CardioSwitch-study)

BACKGROUND AND PURPOSE

The CardioSwitch-study demonstrated that patients with solid tumors who develop cardiotoxicity on capecitabine or 5-fluorouracil (5-FU) treatment can be safely switched to S-1, an alternative fluoropyrimidine (FP). In light of the European Medicines Agency approval of S-1 in metastatic colorectal cancer (mCRC), this analysis provides more detailed safety and efficacy information, and data regarding metastasectomy and/or local ablative therapy (LAT), on the mCRC patients from the original study.

MATERIALS AND METHODS

This retrospective cohort study was conducted at 12 European centers. The primary endpoint was recurrence of cardiotoxicity after switch. For this analysis, safety data are reported for 78 mCRC patients from the CardioSwitch cohort (N = 200). Detailed efficacy and outcomes data were available for 66 mCRC patients.

RESULTS

Data for the safety of S-1 in mCRC patients were similar to the original CardioSwitch cohort and that expected for FP-based treatment, with no new concerns. Recurrent cardiotoxicity (all grade 1) with S-1-based treatment occurred in 4/78 (5%) mCRC patients; all were able to complete FP treatment. Median progression-free survival from initiation of S-1-based treatment was 9.0 months and median overall survival 26.7 months. Metastasectomy and/or LAT was performed in 33/66 (50%) patients, and S-1 was successfully used in recommended neoadjuvant/conversion or adjuvant-like combination regimens and schedules as for standard FPs.

INTERPRETATION

S-1 is a safe and effective FP alternative when mCRC patients are forced to discontinue 5-FU or capecitabine due to cardiotoxicity and can be safely used in the standard recommended regimens, settings, and schedules.

Intestinal Perforation in a patient with peritoneal carcinomatosis from colon cancer treated with Regorafenib. Description of a case and review of the literature

Regorafenib is a multikinase inhibitor approved for treatment of patients with metastatic Colo-Rectal Cancer (mCRC) and Gastro-Intestinal Stromal Tumor (GIST) progression after the administration of other tyrosine-kinase inhibitors such as imatinib and sunitinib. Only a handful of severe side effects such as intestinal perforations and fistulas have been described in the literature in patients undergoing multikinase inhibitor treatment. We report a case of a patient with peritoneal mCRC who experienced an intestinal perforation during the administration of Regorafenib and review the literature. A 48-year-old man with previously resected sigmoid colon cancer and peritoneal metastatic disease under Regorafenib treatment presented to our Emergency Department with severe abdominal pain and asthenia. Abdominal X-ray and contrast-enhanced computed tomography examination revealed an intestinal perforation. The patient underwent emergency surgery which demonstrated acute diffuse peritonitis, necrosis, and perforation of a distal ileal loop affected by peritoneal metastatic disease. The necrosis of peritoneal implants on bowel walls could be regarded as a potential factor leading to intestinal perforation in metastatic colorectal cancer patients undergoing Regorafenib treatment complaining of severe abdominal pain and asthenia. Surgeons, radiologists and oncologists should always keep in mind this rare adverse event during Regorafenib administration. Appropriate diagnostic tests and treatments should be carried out.

Systematic review and non-inferiority meta-analysis of randomised phase II/III trials on S-1-based therapy versus 5-fluorouracil- or capecitabine-based therapy in the treatment of patients with metastatic colorectal cancer

BACKGROUND

S-1 is an oral fluoropyrimidine that is increasingly used in Western countries for the treatment of metastatic colorectal cancer (mCRC). We conducted a non-inferiority meta-analysis on the efficacy of S-1-based therapy versus 5-fluorouracil (5-FU)- or capecitabine-based therapy in the treatment of patients with mCRC.

METHODS

MEDLINE, Embase, the Cochrane Central Register of Controlled Trials and Opengrey were searched for randomised clinical trials until May 2021. Data were extracted for progression-free survival (PFS), overall survival (OS), objective response rate (ORR) and adverse events. Pooled effect estimates, stratified by treatment line, with corresponding 99% confidence intervals (CI) were presented. For PFS, a pre-defined non-inferiority margin (ΔNI) of 1.25 was selected.

RESULTS

Ten studies (n = 2117) were included, of which six studies reported PFS and OS data and 10 studies reported ORR data. S-1-based therapy was shown to be non-inferior to 5-FU/capecitabine-based therapy in terms of PFS (HRtotal 0.95, 99% CI 0.83-1.08) with its CI upper limit well below ΔNI, and at least as efficacious in terms of OS (HRtotal 0.93, 99% CI 0.81-1.07), and ORR (RRtotal 1.06, 99% CI 0.90-1.24).

CONCLUSIONS

S-1-based therapy is non-inferior to 5-FU/capecitabine-based therapy in the treatment of mCRC regarding PFS and at least as efficacious as 5-FU/capecitabine-based therapy in terms of ORR and OS. These data support the use of S-1 in mCRC patients who are intolerant to 5-FU/capecitabine-based treatment.

Application of Approved Cisplatin Derivatives in Combination Therapy against Different Cancer Diseases

The problems with anticancer therapy are resistance and toxicity. From 3000 Cisplatin derivatives tested as antitumor agents, most of them have been rejected, due to toxicity. The aim of current study is the comparison of therapeutic combinations of the currently applied in clinical practice: Cisplatin, Carboplatin, Oxaliplatin, Nedaplatin, Lobaplatin, Heptaplatin, and Satraplatin. The literature data show that the strategies for the development of platinum anticancer agents and bypassing of resistance to Cisplatin derivatives and their toxicity are: combination therapy, Pt IV prodrugs, the targeted nanocarriers. The very important strategy for the improvement of the antitumor effect against different cancers is synergistic combination of Cisplatin derivatives with: (1) anticancer agents—Fluorouracil, Gemcitabine, Cytarabine, Fludarabine, Pemetrexed, Ifosfamide, Irinotecan, Topotecan, Etoposide, Amrubicin, Doxorubicin, Epirubicin, Vinorelbine, Docetaxel, Paclitaxel, Nab-Paclitaxel; (2) modulators of resistant mechanisms; (3) signaling protein inhibitors—Erlotinib; Bortezomib; Everolimus; (4) and immunotherapeutic drugs—Atezolizumab, Avelumab, Bevacizumab, Cemiplimab, Cetuximab, Durvalumab, Erlotinib, Imatinib, Necitumumab, Nimotuzumab, Nivolumab, Onartuzumab, Panitumumab, Pembrolizumab, Rilotumumab, Trastuzumab, Tremelimumab, and Sintilimab. An important approach for overcoming the drug resistance and reduction of toxicity of Cisplatin derivatives is the application of nanocarriers (polymers and liposomes), which provide improved targeted delivery, increased intracellular penetration, selective accumulation in tumor tissue, and enhanced therapeutic efficacy. The advantages of combination therapy are maximum removal of tumor cells in different phases; prevention of resistance; inhibition of the adaptation of tumor cells and their mutations; and reduction of toxicity.

Randomized phase II study of SOX+B-mab versus SOX+C-mab in patients with previously untreated recurrent advanced colorectal cancer with wild-type KRAS (MCSGO-1107 study)

Background

Although chemotherapy for metastatic colorectal cancer (mCRC) has improved, the standard chemotherapy regimens for patients with RAS wild-type mCRC remain debated. This study aimed to compare S-1 and oxaliplatin (SOX) + bevacizumab (B-mab) with SOX + cetuximab (C-mab) in patients with previously untreated recurrent advanced CRC with wild-type KRAS.

Methods

This randomized phase II, open-label, multicenter study compared the efficacy and safety of SOX+B-mab with SOX+C-mab in patients with previously untreated advanced CRC with wild-type KRAS. Between February 2012 and October 2016, 45 patients were enrolled.

Results

Overall response rates were 59.1 and 43.5% (p = 0.29) and disease control rates were 90.9 and 91.3% (p = 0.96) in the SOX+B-mab and SOX+C-mab groups, respectively. Median overall survival (OS) was 25.3 and 15.5 months (HR = 0.607, p = 0.167) and median progression-free survival (PFS) were 11.7 and 5.5 months (HR = 0.558, p = 0.077) in the SOX+B-mab and SOX+C-mab groups, respectively. The OS and PFS of patients with early tumor shrinkage (ETS) were not significantly different in the SOX+B-mab group. However, they were significantly better when ETS was ≥20 in the SOX+C-mab group (p = 0.032 and p = 0.003, respectively).

Conclusions

The efficacy and safety of SOX+B-mab and SOX+C-mab for wild-type KRAS recurrent advanced CRC as first-line chemotherapy were almost the same. Consideration of the treatment strategy based on ETS may improve patient prognosis, especially in patients receiving the SOX+C-mab regimen.

Trial registration

UMIN Clinical Trials Registry (UMIN000006706).

Date of registration: NOV/11/2011.

URL of trial registry record:

https://upload.umin.ac.jp/cgi-open-bin/ctr_e/ctr_view.cgi?recptno=R000007920

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-021-08690-y.

Evaluation of the effect of ultrasound interventional injection of cisplatin in the treatment of liver cancer

OBJECTIVE

To evaluate the effect of ultrasound interventional injection of cisplatin in the treatment of hepatocellular carcinoma (HCC).

METHODS

68 patients with HCC admitted to our hospital from February 2016 to February 2018 were enrolled. According to the different treatment methods, they were divided into a study group and a control group. The control group was treated with hepatic artery embolization chemotherapy (n=34), the study group adopted interventional ultrasound injection of cisplatin (n=34). The clinical treatment effects of the two groups of patients were compared; the liver function and the occurrence of adverse reactions were compared; all patients were followed up for 24 months, and their progressive-free survival (PFS) was also compared.

RESULTS

The study group had higher total effective rate compared with the control group (91.18% vs 67.65%) (P<0.05); the AST, ALT, T-BIL and D-BIL levels of the two groups decreased remarkably after treatment, and the reduction in the study group was more obvious (P<0.05); the levels of VEGF, AFP and CEA of the two groups reduced noticeably after treatment, and the decrease in the study group was more significant (P<0.05); the total incidence of adverse reactions in the study group and the control group was 2.94% and 23.53% respectively, (P<0.05); the two groups were followed up for 24 months, and the disease control rate (DCR) of the control group was 58.82%, significantly lower than 85.29% in the study group; the PFS time of the control group was (15.68±4.23) lower than that of the study group (18.12±5.42) (P<0.05).

CONCLUSION

Interventional ultrasound injection of cisplatin in the treatment of HCC has a definite effect. It can effectively relieve liver damage, reduce adverse reactions, improve serum tumor marker levels, and boost the DCR and PFS time of tumor patients.

S-1 and oxaliplatin versus tegafur-uracil and leucovorin as post-operative adjuvant chemotherapy in patients with high-risk stage III colon cancer: updated 5-year survival of the phase III ACTS-CC 02 trial

Background

The ACTS-CC 02 trial demonstrated that S-1 plus oxaliplatin (SOX) was not superior to tegafur-uracil and leucovorin (UFT/LV) in terms of disease-free survival (DFS) as adjuvant chemotherapy for high-risk stage III colon cancer (any T, N2, or positive nodes around the origin of the feeding arteries). We now report the final overall survival (OS) and subgroup analysis according to the pathological stage (TNM 7th edition) for treatment efficacy.

Patients and methods

Patients who underwent curative resection for pathologically confirmed high-risk stage III colon cancer were randomly assigned to receive either UFT/LV (300 mg/m² of UFT and 75 mg/day of LV on days 1-28, every 35 days, five cycles) or SOX (100 mg/m² of oxaliplatin on day 1 and 80 mg/m²/day of S-1 on days 1-14, every 21 days, eight cycles). The primary endpoint was DFS and the patients’ data were updated in February 2020.

Results

A total of 478 patients in the UFT/LV group and 477 patients in the SOX group were included in the final analysis. With a median follow-up time of 74.3 months, the 5-year DFS rate was 55.2% in the UFT/LV group and 58.1% in the SOX group [stratified hazard ratio (HR) 0.92; 95% confidence interval (CI) 0.76-1.11; P = 0.3973], and the 5-year OS rates were 78.3% and 79.1%, respectively (stratified HR 0.97; 95% CI 0.76-1.24; P = 0.8175). In the subgroup analysis, the 5-year OS rates in patients with T4N2b disease were 51.0% and 64.1% in the UFT/LV and SOX groups, respectively (HR 0.72; 95% CI 0.40-1.31).

Conclusion

Our final analysis reconfirmed that SOX as adjuvant chemotherapy is not superior to UFT/LV in terms of DFS in patients with high-risk stage III colon cancer. The 5-year OS rate was similar in the UFT/LV and SOX groups.

•

This final analysis reconfirmed that SOX is not superior to UFT/LV in high-risk stage III colon cancer in terms of DFS.

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With a median follow-up time of 74.3 months, the 5-year OS rate was similar in both groups.

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The 5-year OS rates in patients with T4N2b disease were 51.0% and 64.1% in the UFT/LV and SOX groups, respectively.

Treatment sequences of patients with advanced colorectal cancer and use of second-line FOLFIRI with antiangiogenic drugs in Japan: A retrospective observational study using an administrative database

The objectives were to describe treatment sequences for advanced colorectal cancer (CRC), use of second-line FOLFIRI (leucovorin, 5-fluorouracil, irinotecan) plus antiangiogenic drug (bevacizumab, ramucirumab, aflibercept beta) therapy, and the factors associated with the duration of antitumor drug treatment from second-line antiangiogenic therapy in Japan. This retrospective observational study was conducted using a Japanese hospital-based administrative database. Patients were enrolled if they started adjuvant therapy (and presumably experienced early recurrence) or first-line treatment for advanced CRC between May 2016 and July 2019, and were analysed until September 2019. Factors associated with overall treatment duration from second-line treatment with FOLFIRI plus antiangiogenic drugs were explored with multivariate Cox regression analysis. The most common first-line treatments were FOLFOX (leucovorin, 5-fluorouracil, oxaliplatin) or CAPOX (capecitabine, oxaliplatin) with bevacizumab (presumed RAS-mutant CRC) and FOLFOX with panitumumab (presumed RAS-wild type CRC). The most common second-line treatments were FOLFIRI-based. Many patients did not transition to subsequent lines of therapy. For second-line treatment, antiangiogenic drugs were prescribed more often for patients with presumed RAS-mutant CRC, right-sided CRC, and independent activities of daily living (ADL). The median duration of second-line FOLFIRI plus antiangiogenic drug treatment was 4.5 months; 66.2% of patients transitioned to third-line therapy. Low body mass index and not fully independent ADL were significantly associated with shorter overall duration of antitumor drug treatment from second-line therapy. Left-sided CRC, presumed RAS-wild type CRC, previous use of oral fluoropyrimidines and use of proteinuria qualitative tests, antihypertensives, or anticholinergics during second-line therapy were significantly associated with longer treatment. Treatment of advanced CRC in Japan is consistent with both international and Japanese guidelines, but transition rates to subsequent therapies need improvement. In addition to antitumor drug treatment, better ADL, higher body mass index, management of hypertension, and proteinuria tests were associated with continuation of sequential therapy that included antiangiogenic drugs.

A meta-analysis of efficacy and safety of S-1 monotherapy or combination therapy as first-line treatment in metastatic colorectal cancer

PURPOSE

To compare the efficacy and safety profile of S-1-based versus non-S-1-based chemotherapy as first-line treatment in mCRC.

METHODS

Relevant randomized controlled trials (RCTs) were obtained from PubMed, Embase, and Ovid databases and the Cochrane library from database set up in May 2018. The RCTs of S-1-based monotherapy or combination therapy as first-line treatment were selected. The impact of S-1-based chemotherapy on progression-free survival (PFS) and overall survival (OS) was assessed by pooling data via RevMan 5.3.

RESULTS

Meta-analysis of 10 RCTs showed that S-1-based chemotherapy significantly improved PFS (HR 0.90, 95% CI 0.84-0.97, P = 0.006). In subgroup analysis, there was a statistically significant increase in PFS when S-1-based chemotherapy was compared with 5-FU-based (HR 0.92, 95% CI 0.84-1.00, P = 0.04) or capecitabine-based chemotherapy (HR 0.85, 95% CI 0.73-0.99, P = 0.04). The meta-analysis of OS (HR 0.95, 95% CI 0.86-1.05, P = 0.36), overall response rate (ORR) (HR 0.99, 95% CI 0.84-1.17, P = 0.90), and disease control rate (DCR) (HR 1.61, 95% CI 0.87-3.00, P = 0.13) showed no statistical significance between S-1-based and non-S-1-based chemotherapy. The statistically significant differences in the meta-analysis indicated less incidence of graded 3-4 leucopenia (OR = 0.30, 95% CI 0.13-0.71, P = 0.006) and hand-foot syndrome (HFS) (OR = 0.24, 95% CI 0.10-0.58, P = 0.001) in the S-1-based chemotherapy, and there was no statistically significant difference for other adverse events.

CONCLUSIONS

S-1-based chemotherapy in mono or combined therapy was an attractive alternative to standard first-line regimen for patients of mCRC.

Readministration of Cancer Drugs in a Patient with Chemorefractory Metastatic Colorectal Cancer

A 63-year-old woman was admitted to our institution for severe pain in her right lower abdomen caused by the perforation of cecal cancer. She underwent emergency surgery, from which she was diagnosed with cecal carcinoma with liver, lung, and lymph node metastases. As she was taking aspirin to prevent cerebral infarction, anti-vascular endothelial growth factor (receptor) antibody and regorafenib therapy were not used. Thus, we started a modified FOLFOX 6+cetuximab regimen. This first-line treatment initially achieved a partial response (PR), but she then developed progressive disease (PD) after 14 months. We changed the regimen to FOLFIRI, followed by trifluridine/tipiracil, but her progression-free survival periods were 2.7 months and 1 month, respectively. Although we cycled through the available array of standard cancer drugs, the patient showed a good performance status, and some benefit from treatment still seemed plausible. We readministered the 5-fluorouracil oral preparation S-1, which maintained stable disease (SD) for 7 months. After PD emerged, we readministered the anti-epidermal growth factor receptor (EGFR) antibody panitumumab for 7.5 months of SD. Finally, 39 months after her diagnosis, she died from rapidly progressing disease. However, her relatively long survival implies that readministering drugs similar to those used in previous regimens might benefit patients with metastatic colorectal cancer.

Update on optimal treatment for metastatic colorectal cancer from the AGITG expert meeting: ESMO congress 2019

Introduction: Outcomes in metastatic colorectal cancer are improving, due to the tailoring of therapy enabled by better understanding of clinical behavior according to molecular subtype.Areas covered: A review of the literature and recent conference presentations was undertaken on the topic of systemic treatment of metastatic colorectal cancer. This review summarizes expert discussion of the current evidence for therapies in metastatic colorectal cancer (mCRC) based on molecular subgrouping.Expert opinion: EGFR-targeted and VEGF-targeted antibodies are now routinely incorporated into treatment strategies for mCRC. EGFR-targeted antibodies are restricted to patients with extended RAS wild-type profiles, with evidence that they should be further restricted to patients with left-sided tumors. Clinically distinct treatment pathways based on tumor RAS, BRAF, HER2 and MMR status, are now clinically applicable. Evidence suggests therapy for additional subgroups will soon be defined; the most advanced being for patients with KRAS G12 C mutation and gene TRK fusion defects.

Meta-analysis of safety and efficacy of S-1-based regimens in treatment of metastatic colorectal cancer

BACKGROUND

In recent years, some studies have found that oral S-1-based regimens are more effective than intravenous FOLFOX4/FOLFIRI regimen in the treatment of metastatic colorectal cancer (mCRC).

AIM

To systematically evaluate the clinical efficacy and safety of S-1-based regimens in the treatment of patients with refractory mCRC by meta-analysis, and to provide evidence-based medicine-related evidence.

METHODS

Controlled trials evaluating S-1-based regimens for the treatment of mCRC from January 2009 to January 2019 were retrieved from VIP database, Wanfang Data, Chinese Biomedical Literature Database, CNKI database, The Cochrane Library, PubMed, and Embase. Meta-analysis of the included studies was conducted with Revman 5.3 software and estimated by odds ratio (OR) and 95% confidence interval (CI).

RESULTS

The results of meta-analysis showed that the 3-year overall survival rate and 3-year recurrence-free survival rate were significantly higher in the study group (OR = 0.65, 95%CI: 0.47-0.89, P = 0.008; OR = 1.45, 95%CI: 1.03-2.06, P = 0.04). The study group had less adverse events than the control group (OR = 0.68, 95%CI: 0.53-0.87, P = 0.002). The incidence of bone marrow suppression, alopecia, nausea and vomiting, and skin reactions in the study group was significantly lower than that in the control group (P < 0.05)

CONCLUSION

S-1-based regimens have better efficacy and adverse event profile in the treatment of refractory mCRC than FOLFOX4/FOLFIRI regimen.

CA19-9 Concentration After First-line Chemotherapy Is Prognostic Predictor of Metastatic Colon Cancer

BACKGROUND/AIM

To evaluate whether the serum levels of CEA or CA19-9 concentration is a useful predictor of survival in patients with metastatic colon cancer (mCC).

PATIENTS AND METHODS

Between 2012 and 2015, 113 patients with mCC who underwent chemotherapy according to the Japanese Colorectal Cancer Treatment Guidelines at four Jikei University Hospitals were enrolled in this study. The two serum tumor makers, CEA and CA19-9 were measured before first-line chemotherapy and at four months thereafter.

RESULTS

Serum CA19-9 concentration at four months after first-line chemotherapy (p=0.003, HR=3.761) and first-line chemotherapy including oxaliplatin (p=0.038, HR=0.312) were independent predictors of survival in patients with mCC. By excluding the transverse colon, only serum CA19-9 concentration at four months after first-line chemotherapy (p=0.005, HR=3.660) was identified as the predictor of survival.

CONCLUSION

Serum CA19-9 concentration after first-line chemotherapy seems to be a useful predictor of survival in patients with mCC.

Efficacy and safety assessment of S-1-based regimens comparing to intravenous fluorouracil-based ones in Asian patients with metastatic colorectal carcinoma: A system review and meta-analysis

BACKGROUND

We performed the present systematic review and meta-analysis to evaluate the efficacy and safety for S-1-based regimens comparing to intravenous fluorouracil-based ones in Asian patients with metastatic colorectal carcinoma (mCRC).

METHODS

Eligible prospective and controlled randomized clinical trials (RCT) were included, of which data were extracted by inclusion criteria and exclusion ones. Odds ratio (OR) and Hazard ratio (HR) of outcomes including objective response rate (ORR), disease control rate (DCR), progressive-free survival (PFS), overall survival (OS), and adverse events (AEs) were explored for the final analysis between the 2 groups.

RESULTS

A total of 23 eligible prospective, controlled RCTs including 2269 patients were enrolled for the pooled analysis. With the meta-analysis of available data, the results of the present research showed that there was no statistical difference on short-term efficacy including ORR (HR = 0.85, 95% CI: 0.71-1.01; P = .07) or DCR (HR = 0.88, 95% CI: 0.69-1.11; P = .27), as well as long-term efficacy including PFS (HR = 1.00, 95% CI: 0.90-1.11; P = .98) or OS (HR = 0.95, 95% CI: 0.82-1.10; P = .50). In addition, the incidences of AEs including leucopenia, neutropenia, and vomiting were statistically lower in S-1-based regimens comparing to intravenous fluorouracil-based ones, regardless of all grade or high grade (all P <.05). However, there were no significant differences detected among other AEs including anemia, thrombocytopenia, increased alanine aminotransferase concentration, stomatitis, anorexia, diarrhea, hand-foot syndrome (HFS), or sensory neuropathy among the 2 groups (all P >.05).

CONCLUSIONS

The present meta-analysis revealed that S-1-based regimens might be associated with comparable efficacy, as well as lower risk of leucopenia, neutropenia, and vomiting at all/high grade comparing to intravenous fluorouracil-based ones in Asian patients with mCRC.

Epidermal growth factor receptor-targeted molecular imaging of colorectal tumors: Detection and treatment evaluation of tumors in animal models

To overcome the problem of overlooking colorectal tumors, a new and highly sensitive modality of colonoscopy is needed. Moreover, it is also important to establish a new modality to evaluate viable tumor volume in primary lesions of colorectal cancer (CRC) during chemotherapy. Therefore, we carried out molecular imaging of colorectal tumors targeting epidermal growth factor receptor (EGFR), which is highly expressed on tumor cells, for evaluating chemotherapeutic efficacy and for endoscopic detection of colorectal adenomas. We first attempted to image five CRC cell lines with various levels of EGFR expression using an Alexa Fluor-labeled anti-EGFR monoclonal antibody (AF-EGFR-Ab). A strong fluorescence signal was observed in the cells depending on the level of EGFR expression. When nude mice xenografted with LIM1215 CRC cells, which highly express EGFR, were i.v. injected with AF-EGFR-Ab, a strong fluorescence signal appeared in the tumor with a high signal to noise ratio, peaking at 48 hours after injection and then gradually decreasing, as shown using an IVIS Spectrum system. When the xenografted mice were treated with 5-fluorouracil, fluorescence intensity in the tumor decreased in proportion to the viable tumor cell volume. Moreover, when the colorectum of azoxymethane-treated rats was observed using a thin fluorescent endoscope with AF-EGFR-Ab, all 10 small colorectal adenomas (≤3 mm) were detected with a clear fluorescence signal. These preliminary results of animal experiments suggest that EGFR-targeted fluorescent molecular imaging may be useful for quantitatively evaluating cell viability in CRC during chemotherapy, and also for detecting small adenomas using a fluorescent endoscope.