Distribution of the first metastatic lymph node in colon cancer and its clinical significance

INTRODUCTION

The pattern of distribution of lymph node metastasis in resected specimens of colon cancer has been rarely reported in the English literature. The aim of this study was to determine the location of the first metastatic lymph node, giving insight into the drainage pattern of colon cancer lymphatics.

METHOD

All lymph nodes in the mesentery of the resected specimen were carefully harvested and their precise locations documented. Patients with a single metastatic node in the resected specimen were included in the study.

RESULTS

Ninety-three patients with only one metastatic lymph node found on histology were studied. The mean number of lymph nodes per specimen was 22.3 (range: 8-72). The patients' first metastatic node was not directly below the tumour in 48% of cases. The first metastatic node was found in the region either along the feeding vessels (skipping the pericolic nodes) or in the pericolic area outside 5 cm on either side of the tumour edge in 18% of cases. No factors were found to be predictive for lymph node metastasis occurring elsewhere other than in the pericolic region just below the tumour.

CONCLUSION

Although there has been recent resurgence of interest in using sentinel node biopsy to limit surgical dissection to facilitate minimally access and natural orifice surgery, the present study is a warning that this may compromise oncological clearance. Radical surgery should remain standard practice for colorectal cancer.

Understanding the anatomy of lymphatic drainage and the use of blue-dye mapping to determine the extent of lymphadenectomy in rectal cancer surgery: unresolved issues

OBJECTIVE

This paper reviews the literature on the pathways of lymphatic drainage of the rectum and their significance in radical cancer surgery.

METHOD

This paper reviews some of the seminal works on the lymphatic drainage of the rectum and its surgical implications when operating on patients with rectal cancer. Publications were searched via Medline, sourced from reference lists and by cross referencing with the most widely cited papers.

RESULTS

The classical European description of the anatomy of the lymphatic drainage of the rectum is presented. Early lymphatic mapping techniques and the role of newer technologies in lymphatic mapping, including sentinel lymph node mapping are discussed. The differing philosophies between Western practice, of dissection in the plane of the fascia propria and the Japanese wider pelvic lymphadenectomy are discussed.

CONCLUSIONS

A clear understanding of the regional lymphatic drainage of the rectum and precise anatomical mobilisation of the rectum is the surgical cornerstone to excellent locoregional control of rectal cancer. The success of the differing Western and Japanese philosophies on the degree of pelvic lymphadenectomy suggests a possible role for 'selective wide pelvic lymphadectomy'. Mapping lateral lymphatic drainage pathways could augment the selection process for radiotherapy.

Association of pharmacokinetics and germ-line mutations in EGFR and ABC transporters with erlotinib toxicity in patients with non-small cell lung cancer (NSCLC)

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Background: Erlotinib demonstrates substantial inter-individual differences in response and the development of skin rash (grade≥2) was correlated with efficacy. Erlotinib interacts with its target EGFR and the efflux transporter ABCB1 and ABCG2. EGFR CA repeat is associated with incidence of skin rash. A 421C>A SNP in ABCG2 and 1236C>T, 2677 G>(T/A), and 3435C>T SNPs in ABCB1 are associated with reduced protein expression. The aim of this study was to evaluate the effects of these variants and pharmacokinetics of erlotinib on toxicity grade in Japanese patients treating single agent erlotinib. Methods: Twenty-two patients with NSCLC received erlotinib orally at 150 mg/day and plasma levels of erlotinib were measured on days 1(D1), 8(D8), and stable phase (>day 14) by high-performance liquid chromatography. DNA from plasma was screened for SNPs in the EGFR, ABCB1, and ABCG2 genes using direct nucleotide sequencing or TaqMan assay. Eligibility criteria included: performance status (PS) < 3, age < 75, stage IIIB-IV, and written informed consent. Results: The mean Cmax (±SD) of D1 and D8 were 1.8 ± 1.0 and 3.1 ± 1.4 μg/ml, respectively. Trough concentration (Cmin) at D1 and steady state were 0.9 and 1.7 μg/ml, respectively. Grade 1–2 skin rash or diarrhea occurred in 95% of patients. One patient (Cmax at D1, 3.0 μg/ml) developed interstitial lung disease after continuous treatment with erlotinib for 3 days. The area under curves and Cmax on D1 were correlated with the severity of skin rash (p=0.05 and 0.01), however, Cmin were not correlated. Patients with homozygous variant and heterozygous for ABCB1 1236C>T, 2677 G>(T/A), and 3435C>T genotype as compared to patients carrying the wild-type were associated with higher Cmin at steady state (2.4 vs 1.2 μg/ml, p=0.01). EGFR CA repeat and AGCG2 421C>A genotype were not associated with any pharmacokinetic parameters. All Patients (n=4) with homozygous variant for ABCB1 1236TT- 2677TT/TA/AA-3435TT developed grade≥2 skin rash or diarrhea. Conclusions: The present study suggests that ABCB1 gene polymorphism is associated with the variable toxicity and pharmacokinetics to erlotinib treatment.

No significant financial relationships to disclose.

Effect of direct hemoperfusion using polymyxin B immobilized fiber on inflammatory mediators in patients with severe sepsis and septic shock

The objective of this study was to investigate retrospectively the effect of direct hemoperfusion using polymyxin B immobilized fiber (PMX-DHP) in a cartridge to remove endotoxin on inflammatory mediators in septic patients. PMX-DHP was performed 59 times in 40 patients with severe sepsis and septic shock due to gram-negative bacterial infection. Mean age and APACHE II score were 63 years and 22, respectively. The first treatments with PMX-DHP were started when patient hemodynamics were unstable even after conventional therapies. The second treatments were performed in 19 patients whose hemodynamics were still unstable after the first PMX-DHP. The changes in inflammatory mediator levels were compared from baseline to post treatment with PMX-DHP. Statistical differences were calculated using the Wilcoxon rank sum test. Plasma endotoxin could be detected in 34 patients, which was significantly decreased in 20 cases measured by a chromogenic kinetic limulus amebocyte lysate assay (p=0.0254) and in 14 cases measured by a new limulus turbidimetric time assay (p=0.0196). Monocyte counts in peripheral blood decreased significantly (p=0.0402). Interleukin-6 decreased significantly (p=0.0020). Blood pyruvate also decreased significantly (p=0.0025). At the same time, mean arterial pressure, pulse pressure, systemic vascular resistance index, and urine output were significantly increased. These results indicated that PMX-DHP could decrease inflammatory mediators and be effective to interrupt the pathogenic sequence leading to septic shock due to gram-negative bacterial infection.

Plasma and erythrocyte lipids in sickle cell anaemia

The content and composition of plasma and erythrocyte lipids from individuals having sickle cell anaemia has been determined. The plasma contains a significantly reduced content of both cholesterol and phospholipid while the ratio of cholesteryl ester to total cholesterol, the distribution of phospholipid classes, triglyceride concentration and the fatty acid content were similar to normal values. However, the free glycerol content of the plasma was eight-fold higher than normal. Erythrocyte lipids contain an elevated level of cholesterol and control levels of phospholipid content, phospholipid distribution and fatty acid content. The plasma was separated by ultracentrifugation into VLDL (density less than 1.006), LDL (1.006 less than d less than 1.063) and HDL (1.063 less than d less than 1.21). Significant decreases in cholesterol and phospholipid were observed in LDL and HDL.

Detecting of coronary dissection by coronary magnetic resonance

A 75-year-old man, who had a history of coronary dissection after percutaneous coronary intervention in left anterior descending coronary artery, underwent coronary magnetic resonance. Magnetic resonance demonstrated coronary dissection in the distal portion of the left anterior descending artery. Both the true lumen with thick vessel wall and the false lumen with thin vessel wall were demonstrated in the cross-sectional images using T1-weighed black blood technique and T2-weighed black blood technique. Soft plaque was located at the twelve o'clock in the true lumen. Invasive coronary angiogram showed long coronary dissection from middle to distal portion of left anterior descending coronary artery. Magnetic resonance was thought to be useful to detect and follow up the coronary dissection noninvasively.

A trilogy of primary prevention statin trials. Panel discussion

Presented is a report of a panel discussion held as part of the ISA 2006 Sankyo Forum titled "A Trilogy of Primary Prevention Statin Trials--The Impact of These Landmark Studies on Clinical Practice," Rome, Italy, June 2006. The themes of the panel discussion were the design features of three trials, WOSCOPS, AFCAPS/TexCAPS, and Japan's MEGA Study; comparison of their primary endpoints; and the implications of their results. Among the topics discussed by the panel of experts from Japan, USA, and UK were observations on the benefits associated with pravastatin at low dose as demonstrated in the MEGA Study as well as that study's implications for women, who represented the majority of subjects. Several suggestions were put forth to explain how the low dose used in MEGA elicited similar LDL-C reductions to those observed in WOSCOPS and AFCAPS/TexCAPS at higher doses including the body size hypothesis, genetic variation, and statin-diet interaction. It was felt that in Japan, the current guidelines are adequate; there seemed no merit in radically reducing LDL-C levels since in the Japanese population the risk is generally low. Japanese physicians tend to use small doses of statin and believe that these are effective in lowering cholesterol sufficiently with few side effects and encourage good compliance.

Correlative study of EGFR mutations or protein expressions of EGFR, phosphorylated EGFR, HER2, phosphorylated HER2 and IGFR-1 with gefitinib sensitivity in patients with non-small cell lung cancer: Results of West Japan Thoracic Oncology Group trial (WJTO)

14008

Background: Both epidermal growth factor receptor (EGFR) mutation and gene copy number of HER2, a member of EGFR family, are associated with gefitinib sensitivity. We carried out a correlative study to determine the relationships between EGFR mutations, EGFR or HER2 protein expressions, their activation status (pEGFR, pHER2) or insulin-like growth factor receptor 1 (IGFR-1) protein expressions and clinical outcomes after gefitinib treatment in advanced NSCLC. Method: Tumors from patients (pts) were evaluated for EGFR mutations by DNA sequence, and for protein expressions of EGFR, pEGFR, HER2, pHER2 and IGFR-1 by immuno-histochemistry. Time to progression (TTP) was calculated by the Kaplan-Meier method; groups were compared using the log-rank test. Risk factors associated with TTP were evaluated with Cox proportional hazard regression modeling. Correlation between EGFR mutation and response was evaluated by Fisher’s direct method. Relationship between each protein expression and response was tested by two-sided. Primary endpoint was to detect biomarkers to predict gefitinib sensitivity. Results: From Dec. 2003 to Dec. 2005, 103 consecutive pts were enrolled onto the study, and received gefitinib until disease progression. Median age was 68 years, female (58%), adenocarcinoma (83%), never smoker (55%) and no previous chemotherapy (49%). 98 pts were evaluable for efficacies, toxicities and gene analyses. Forty-one pts (42%) had EGFR mutations; 14 pts had deletional mutation in exon 19, 27 pts had missense mutation (L858R) in exon 21. EGFR mutations were significantly related to response (62 vs. 26%; P = 0.001), disease control rate (92 vs. 65%; P = 0.003) and TTP (median, 10.1 vs. 5.1months; hazard ratio = 0.64; P = 0.048). Both pEGFR (0, +1 vs. =+2; P = 0.002,) and pHER2 (0 vs. =+1; P = 0.001) expressions are significantly associated with incidence of EGFR mutation. Conclusions: EGFR mutation was a significant predictive biomarker of response to gefitinib. Phosphorylated EGFR protein expression is a potent replaceable biomarker for EGFR mutation.

No significant financial relationships to disclose.

Multi-institutional phase II study of carboplatin-gemcitabine combination chemotherapy in elderly patients (pts) with advanced non-small cell lung cancer (NSCLC)

18179

Background: Because elderly pts may tolerate platinum-based combination chemotherapy poorly, single-agent chemotherapy is selected for the treatment regimen. However, retrospective subgroup analyses have consistently indicated that elderly pts indeed benefit from platinum-based combination chemotherapy as well as their younger counterparts. This phase II study evaluated the efficacy and safety of carboplatin-gemcitabine combination chemotherapy in elderly pts with advanced NSCLC. Methods: Fifty-four pts aged more than 70 years old (median, 77; range, 70–88) with previously untreated advanced NSCLC were enrolled on this trial. Additional criteria included the presence of measurable lesions, an Eastern Cooperative Oncology Group performance status of 0 or 1, and adequate organ function. Pts received carboplatin at an area under the curve of 4 mg/ml/min on the first day and gemcitabine at 1000 mg/m2 on the first and eighth day of consecutive 3 week periods. The primary endpoint was to determine the objective response rate of this platinum-doublet regimen. The RECIST criteria were used to measure response. Results: Enrolled pts included 15/39 with stage IIIB/IV diseases. Fifty-one out of enrolled pts were eligible for efficacy and safety analyses. The median number of treatment cycles was 4 (range, 1–7). Fifteen partial responses (response rate: 29%) were obtained. The median TTP was 118 days. Hematological toxicities of grade 3/4 included leukopenia (46%), neutropenia (72%) and thrombocytopenia (50%). Non-hematological toxicities of grade 3/4 included nausea (6%), appetite loss (7%), fatigue (7%) and infection (9%). Conclusions: The combination carboplatin-gemcitabine at these doses has shown activity with a favorable toxicity profile for fit elderly pts with advanced NSCLC.

No significant financial relationships to disclose.

Non-invasive visualization of the lipid product of class I PI3K in transgenic mouse models

PI3Ks (phosphoinositide 3-kinases) regulate many critical cellular responses by producing PI(3,4,5)P3 (phosphatidylinositol 3,4,5-trisphosphate). To facilitate the spatio-temporal characterization of PI(3,4,5)P3 in living primary cells, we generated a novel strain of transgenic mice [AktPH (Akt pleckstrin homology domain)–GFP (green fluorescent protein) Tg (transgenic) mice] that express a fluorescent bioprobe for PI(3,4,5)P3/PI(3,4)P2 (phosphatidylinositol 3,4-bisphosphate). By crossing AktPH–GFP Tg mice with strains of gene-targeted ‘knockout’ mice lacking a particular phosphoinositide-metabolizing enzyme, we have been able to evaluate the contribution of each enzyme to PI(3,4,5)P3 localization in migrating neutrophils. Our results indicate that PI3Kγ and the PI(3,4,5)P3 phosphatase SHIP1 [SH2 (Src homology 2)-containing inositol phosphatase-1] are the key regulators of PI(3,4,5)P3 dynamics during fMet-Leu-Phe (N-formylmethionyl-leucylphenylalanine; ‘chemotactic peptide’)-stimulated neutrophil migration. Our study has also validated the fluorescent transgenic strategy for studying PI(3,4,5)P3 metabolism in physiological and pathological situations.

Bond Fluctuation of S/Se Anchoring Observed in Single-Molecule Conductance Measurements using the Point Contact Method with Scanning Tunneling Microscopy

Conductance was measured for the single molecules with S/Se anchoring on a Au surface using the point contact method with scanning tunneling microscopy that enables us to selectively perform a repeated analysis of a chosen target molecule. Apparent conductance changes observed in sequential measurements suggest the existence of bond fluctuation among the adsorption sites.

JNK1-dependent antimitotic activity of thiazolidin compounds in human non-small-cell lung and colon cancer cells

We recently identified two thiazolidin compounds, 5-[(4-methylphenyl)methylene]-2-(phenylamino)-4(5H)-thiazolone (MMPT) and 5-(2,4-dihydroxybenzylidene)-2-(phenylimino)-1,3-thiazolidin (DBPT), that inhibit the growth of human non-small-cell lung and colon cancer cells independent of P-glycoprotein and p53 status. Here we further investigated the mechanism by which these thiazolidin compounds mediate their anticancer effects. Treatment of cancer cells with MMPT and DBPT led to a time-dependent accumulation of cells arrested in the G2/M phase with modulation of the expression of proteins such as cyclin B1, cdc25C, and phosphorylated histone H3. Moreover, treatment with MMPT and DBPT increased M-phase arrest with abnormal spindle formation. DBPT-mediated G2/M phase arrest and phosphorylation of cdc25C and histone H3 were abrogated when JNK activation was blocked either with SP600125, a specific JNK inhibitor, or a dominant-negative JNK1 gene. Moreover, DBPT-mediated microtubule disruption was also blocked by SP600125 treatment. Our results demonstrate that thiazolidin compounds can effectively induce G2/M arrest in cancer cells and that this G2/M arrest requires JNK activation.

Factors related to home discharge of cerebrovascular disease patients: 1-year follow-up interview survey of caregivers of hospitalized patients in 53 acute care hospitals in Japan

In Japan, many disabled elderly people remain hospitalized for long periods. Cerebrovascular diseases (CVD) are the most causes responsible for such disability. To examine the predictors of home discharge in CVD patients, we performed a 1-year follow-up interview of the main caregivers of patients hospitalized with a CVD event. The initial cohort consisted of CVD patients hospitalized in all the second level emergency and general hospitals in Ibaraki Prefecture in February 1992 (N=888 patients in 53 hospitals). In the following year, we performed an interview survey of the main caregivers of these CVD patients. The survey items included the characteristics of the patients (including medical and socioeconomic conditions), caregivers, and family members. The final study population included the main caregivers of 187 home patients and 90 institutionalized patients. We compared these two groups in terms of predictors of discharge to home. The results of multiple logistic regression analysis showed that the following seven factors were related to home discharge; better baseline activities of daily living (ADL), larger improvement in ADL, larger family size, spouse as the caregiver, caregiver without a full-time job, better economic status of the caregiver, and sources of the patient's income. Our study indicated that the caregiver's conditions were closely related to home discharge of the CVD patients. More attention should, therefore, be centered on the caregiver's well-being and economic aspects as well as the patient's conditions in order to encourage home discharge of stroke patients.