MICROVESSEL DENSITY USING ENDOGLIN (CD 105)EXPRESSION IN RECTAL ADENOCARCINOMA TREATED BY ADJUVANT POSTOPERATIVE CHEMORADIOTHERAPY

Konference: 2007 ECLU Congress ESMO - účast ČR

Kategorie: Kolorektální karcinom

Téma: Colorectal cancer

Číslo abstraktu: 039P

Autoři: Doc. MUDr. Josef Dvořák, Ph.D.; MUDr. Markéta Tomšová, Ph.D.; prof. MUDr. Bohuslav Melichar, Ph.D.; MUDr. Pavel Veselý, Ph.D.; MUDr. Věra Tyčová; doc. MUDr. Milan Vošmik, Ph.D.; prof. MUDr. Jiří Petera, Ph.D.

Purpose: To evaluate microvessel density (MVD) using endoglin (CD 105) expression in locally advanced rectal adenocarcinoma treated by postoperative adjuvant chemoradiotherapy.

Patients and Methods: From 1/2000 to 3/2004, 39 patients (pts), 27 males and 12 females, median age 64 (36-78) years, with rectal adenocarcinoma were treated. Pathologic TNM stage was as follows: 26 (67%) pts stage II and 13 (33%) pts stage III. Adjuvant postoperative chemoradiotherapy follows after (R0) resection in 29 (74.5%)pts, (R1) in 6 pts and (R2) in 4 pts. Chemoradiotherapy consisted of external beam radiotherapy 45-54 Gy in 25-30 fractions, 1.8 Gy daily, with concomittant 5-FU 200 mg/ m2 /day in continuous infusion. In all pts was immunohistochemically investigasted MVD using endoglin (CD 105) expression with mouse monoclonal antihuman endoglin, clone SN6h, DakoCytomation, dilution 1:5. It comprised of two steps: firstly, foci with the highest density of capillaries (‘hot spots’) were identified in slides stained with antibodies against CD 105 using low magnification (10x objective lens). Secondly, the capillaries within the ‘hot spots’ were quantified using higher magnification (20x objective lens). The mean number and the maximum number of capillaries were evaluated. Survival curves (determined by Kaplan - Meier method)were compared by log-rank test.

Results: At the date of evaluation (January 31st, 2007) 23 pts were alive. The median of survival was 1885 days (95% C.L.: 1353-1885) days. One-year survival was 95% (95% C.L.: 88%-100%), five-years survival 50% (95% C.L.: 30%-70%). Nine (23%) pts had recurrence. Median of mean MVD was 26.7 (7.7-71.9) MV/mm2, median of maximum MVD 36.8 (10.5-75.8) MV/mm2. The results of MVD were divided into 2 groups: £ 26.7 MV/mm2 (20 pts) and > 26.7 MV/mm2 (19 pts). Survival curves for these 2 groups were not statistically different at the level 0.05.

Conclusions: The results of this pilot study demonstrate microvessel density using endoglin (CD 105) expression in locally advanced rectal adenocarcinoma treated by postoperative adjuvant chemoradiotherapy.

Acknowledgement: Supported by the research project MZO 00179906.

Datum přednesení příspěvku: 5. 7. 2007