Effectiveness of 5-Fluorouracil and Hypertonic Glucose in the Prevention of Post-mastectomy Seroma in an Experimental Animal Model

INTRODUCTION

Seroma is a frequent complication that can affect the final result of reconstructive and cosmetic surgeries.

METHODOLOGY

This study evaluated the effectiveness of 5-Fluorouracil and 75% hypertonic glucose in preventing seroma in a mastectomy rat model, as well as cellular and vascular events in adjacent tissues. A left mastectomy with lymphadenectomy was performed in 60 Wistar-Albino female rats. Animals randomly allocated to the control group (Group I; n = 20) were sutured right after mastectomy. The intervention groups received 1.0 mL of 75% hypertonic glucose (Group II; n = 20) or 1.0 mL of 5-Fluorouracil (Group III; n = 20) at the surgical site before suturing. The assessment of the presence of seroma was performed in all animals at 24, 48, and 72 h and on the 7th and 12th postoperative day. After the 12th day, a tissue sample was taken from the surgical site and sent for histological analysis. The occurrence of seroma was assessed using GEE. A significance level of 5% was adopted.

RESULTS

Differences in seroma formation over time were observed for both Control Group I (p=0.041) and Intervention Group II (p<0.001). In Intervention Group III, there was no difference in the percentage and volume of seroma across the assessment points (p=0.627). When both the Control and Intervention Group II were compared to Intervention Group III, we found a reduction in seroma formation in the last group. The reduction in the inflammatory process was more regular to Intervention Group III.

CONCLUSION

In this animal model, 5-Fluorouracil was more effective in preventing seroma formation than 75% Hypertonic Glucose. No Level Assigned This journal requires that authors assign a level of evidence to each submission to which Evidence-Based Medicine rankings are applicable. This excludes Review Articles, Book Reviews, and manuscripts that concern Basic Science, Animal Studies, Cadaver Studies, and Experimental Studies. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Nanoemulsions and nanoparticles for non-melanoma skin cancer: effects of lipid materials

Basal cell carcinomas and squamous cell carcinomas are non-melanoma skin cancers reported to be among the most common malignancies, being responsible for high human morbidity. Conventional chemotherapy applied to these conditions shows non-specific targeting, thus severe adverse side effects are also commonly reported. New therapeutic strategies based on nanoparticulates technology have emerged as alternatives for site specific chemotherapy. Among the different types of nanoparticulates, lipid nanoemulsions and nanoparticles have several advantages for topical delivery of poorly soluble chemotherapeutics. These particles show sustained drug release and protection of loaded drugs from chemical degradation. This technology is promising to enhance the intracellular concentration of drugs and consequently reduce the cytotoxicity of skin chemotherapy.

Abstract P1-01-28: What is the actual impact of micrometastases in sentinel lymph nodes in regards to global survival and disease free survival

OBJECTIVE: Assess the clinical relevance of micro metastasis in sentinel lymph nodes in the overall survival and disease free survival of 1,211 patients undergoing sentinel lymph node biopsy.

METHODS: Retrospective cohort study including 1,211 patients undergoing consecutive SLB from 1998 to 2010. SLB were performed in patients with invasive carcinoma of the breast with clinically negative axilla. Age, tumor size, and histologic grades, estrogen and progesterone receptors expression, HER-2, lymphovascular invasion and size of metastases in lymph nodes were assessed. Tumor sizes were divided according to pathologic staging into pT1(&lt; 2,0mm) and pT2(&gt;2,0mm). Lymph nodes were classified as negative (pN0), positive with micro metastases with diameter ranging from 0,21mm to 2,0mm(pN1mi) and positive with macro metastases with diameter greater than 2,0mm(pN1). Statistical analyses were performed by the Likelihood ratio test or Chi-square test for insufficient samples between macro metastases and micro metastases in SLB. Time was considered in months and the overall follow-up time was 125 months and mean time was 65 months. Local regional and distant recurrences were considered as events for disease free survival and Kaplan-Meier survival functions were constructed, testing time between metastases sizes in SLB using the Log-rank test, with a significance level of 5%.

RESULTS: Of the studied variables, lymphovascular invasion(p = 0,068) and local regional and distant metastases(p = 0,002) had a statistically significant association with overall survival. Tumor size(p = 0,016); lymph vascular invasion(p = 0,002) and metastases types in sentinel lymph node(p &lt; 0,001) were associated to disease free survival. In the association tests with types of metastases in sentinel lymph node, the following were statistically significant: age(p = 0,004), tumor size(p &lt; 0,001), lymph vascular invasion(p &lt; 0,001) and local regional and distant recurrences. In the interim and final Cox regression analysis, macro metastases were the only statistically relevant factor for disease free survival(p &lt; 0,001).

CONCLUSION: The presence of micro metastases(pN1mi) in sentinel lymph node is associated to a prognosis similar to that of negative axilla patients(pN0), indicating that other risk factors for local regional and systemic recurrences should be taken into account.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-01-28.

Breast Cancer Gene Expression Profile in Post-Menopausal Patients Supplemented with Vitamin D

Vitamin D supplementation is indicated for post-menopausal women to prevent osteoporosis and lower 25(OH)2D3 or 1,25(OH)2D3 serum levels have been associated with breast cancer incidence or prognosis (metastasis). The antiproliferative effects of vitamin D are observed in breast cancer cell lines exposed to phamacological doses of calcitriol (1,25(OH)2D3, 100nM) but whether physiological doses are sufficient to produce growth inhibition in vivo is not known. The aim of our study was to investigate gene expression profile changes of breast cancer samples from patients supplemented with calcitriol, presenting an anti-proliferative effect on the tumor. Post-menopausal women diagnosed with breast cancer were instructed to take one (0.25ug/day, n=8) or two (0.50ug/day, n=8) tablets of calcitriol after tumor biopsy. Median time of supplementation was 30 days. Sixteen tumor samples were collected during biopsy (before supplementation) and breast surgery (after supplementation). Proliferation index was evaluated by tumor Ki-67 immunohistochemistry (IHC) expression in breast cancer samples before and after calcitirol supplementation and 1000 cells were counted by three observers (p &lt; 0,001, Pearson's correlation). After establishing a counting error between observers, the cut-off value was fixed in 26.53% (percentile 60%) to define response. Patients were then categorized as responsive (a reduction of more than 26.53% on positive Ki-67 positive cells) and non-responsive (difference between samples before and after supplementation not exceeding 26.53%). Among our sixteen patients, all were categorized as responsive to calcitriol supplementation except for two. So far, gene expression profile of two patients (both categorized as responsive) has been analyzed using the U133 Plus 2.0 Affymetrix Gene Chips from 100ng of total RNA. To verify signalling pathways possibly involved in response to vitamin D exposure, additional five samples from a parallel study, in which breast cancer samples from post menopausal patients were collected at surgery and treated in vitro with a low concentration of calcitriol, 0.5nM (that can be attained with subcutaneous administration of doses of 8ug calcitriol, without hypercalcemia) for 24h, were included in the analysis. All samples had RNA hybridized to the same gene chips. Results were normalized and analyzed using RMA and Mev.TM4 softwares. CYP24A1, a target gene of vitamin D, presented a positive regulation after calcitriol supplementation in all samples analyzed. Differentially expressed genes were involved in the regulation of cell cycle [SMAD2, cyclin E, YWHAQ (14-3-3 family] and calcium signalling (HTR7, PTGER1 and PTGER2). Our results indicate that the tumor proliferation index is reduced upon calcitriol supplementation. Moreover, potentially regulated pathways in breast cancer specimens after administration of low doses of calcitriol are regulation of cell cycle and calcium signaling.Supported by FAPESP 2007/01111-0 – 2007/04799-2

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 6128.

A new dynamometric technique to measure and locate endocranial structures. Preliminary report

An apparatus for measuring and recording the resistance to penetration of endocranial tissue has been planned and built. The probe carrier, driven by a constant-speed electric motor, is fitted onto a stereotactic head frame which is used to guide the tool to the intended target. The displacement and resistance encountered when the tool penetrates intracranial structures are measured and recorded on an x-y recorder. Preliminary tests performed on calf brain specimens have documented that the apparatus can measure the different consistencies of normal cerebral tissue and suggest a new technique for morphological investigations based on the mechanical consistency of normal and pathological organic tissue. Moreover, the hypothesis of a plastic deformation in cerebral tissue has been confirmed, in that the same apparatus permits one to measure the displacement of tissues caused by the advancement of the surgical tool.