ABSTRACTS 833

326. Clinical Evaluation of Nerve-sparing Surgery Combined with

Preoperative Radiotherapy in Rectal Cancer Patients

Y. Barsukov1, Z. Mammadli1, S. Pozdnyakov1, V. Kulushev1

1 N.N. Blokhin Russian Research Cancer Center, Colorectal Cancer,

Moscow, Russian Federation

Traditional rectal cancer surgery has been burdened with a high rate of

sexual and urinary dysfunctions due to intraoperative injury or the cutting

of the sympathetic and/or parasympathetic nerves. The experience ac-

quired in the last ten years with total mesorectal excisions has permitted

the use of the ’nerve-sparing’ technique. Increased understanding of the

anatomical and physiological background and improved surgical tech-

niques have lead to a reduction of complication rates. Current study was

initiated to investigate how nerve-sparing surgery may prevent urogenitary

dysfunction in rectal cancer patients treated with multimodal approach.

73 patients were included in trial between April 2011 and January

2012. Patients has different stages of rectal cancer T2-4N�Mo and were

treated by preoperative radiotherapy 25-40Gy in combination with chemo-

therapy. Surgery with autonomic nerve preservation was done in 49 pa-

tients, partial unilateral preservation in 10 cases and in 14 case

autonomic nerve preservation (ANP) techniques was impossible due to lo-

cal cancer spread. All patients filled out The International Prostate Symp-

tom Score (IPSS) before after surgery.

Investigation showed difference in groups: in group with (ANP) full re-

covery according IPSS scale. Patients with partial resection of autonomic

nerves - normal bladder function restored after catheter removal on day 5

in 20% patients and on days 6-7 in rest 80%. Group without case auto-

nomic nerve preservation naturally showed worst results * in 12 out of

14 patients second bladder catheterisation required with electrostimulation

of bladder. Only 2 patients showed full recovery after 3 month.

Conclusion: Preservation of urinary function in previously irradiated

advanced rectal cancer patient~Os possible with autonomic nerve preserva-

tion surgery.

327. Treatment and Oncological Outcome of Locally Advanced Rectal

Cancer in the Elderly

K. Woensdregt1, R.G. Orsini1, S. Bosman1, I.H.J.T. De Hingh1,

G.A.P. Nieuwenhuijzen1, H.J.T. Rutten1

1 Catharina-ziekenhuis, Surgery, Eindhoven, The Netherlands

Background: Currently >50% of patients with rectal cancer is � 70

years old. Elderly often have comorbidities and their clinical and patholog-

ical characteristics may differ substantially from younger patients. This

study describes treatment, outcome and survival of elderly with locally ad-

vanced rectal cancer (LARC) treated in our institution during a period of

16 years in order to enable better patient-tailored care.

Methods: All patients aged � 70 years who underwent LARC surgery

between 1995-2011 were selected (N¼194). Clinical data were collected

retrospectively including type of surgery, (neo)adjuvant therapy, disease

recurrence and mortality. Prognostic factors were analyzed with univariate

and multivariate cox regression models.

Results: Mean age at time of surgery was 76.3 years. Mean time of

follow-up (FU) was 30.9 months. 100 patients (51.5%) received neo-adju-

vant treatment with radiochemotherapy, 29.4% (N¼57) received radiother-

apy only and 10.8% (N¼21) received no neo-adjuvant treatment. All

patients received TME surgery. 44.3% (N¼86) received a resection with

restoration of bowel continuity and 38.7% (N¼75) underwent abdomino-

perineal excision. During FU 78.4% of patients remained disease free,

5.2% developed a local recurrence, 13.4% metastatic disease and 2.6%

both. At the end of FU 79 patients (40.8%) were deceased, of which 30

(38.0%) died of rectal cancer and 49 (62.0%) died due to other causes.

The 5-year overall survival of our population was 44.7%, the 5-year cancer

specific survival was 68.1% and the 5-year relapse free survival was

55.7%.

After multivariate analysis pN stage appeared to be a significant prog-

nostic factor for overall, cancer specific and relapse free survival

(p¼0.005, p<0.001, p¼0.023 respectively). Radical resection was

significant for relapse free survival (p<0,001), the development of distant

metastasis (p¼0.026), local recurrence (p¼0,019) and for cancer specific

survival (p¼0.019) but not for overall survival.

Conclusion: Radical resection is the most important prognostic factor

for relapse free survival in elderly patients with LARC, but it is not signif-

icant regarding overall survival. The hypothesis that elderly patients die

from other causes than LARC, such as comorbidities, is supported by

the cause of death, which showed a non-LARC related death in 62.0%. De-

spite this relative high incidence of death due to other causes, radical sur-

gery remains the cornerstone in the treatment of these patients.

328. CD45-FITC and CD146-PE Measurement as Marker of

Circulating Endothelial Cells in Patients with Colorectal Cancer

F. Lumachi1, F. Marino2, G.B. Chiara3, S.M.M. Basso3

1 University of Padova School of Medicine, Surgical Oncological &

Gastroenterological Sciences (DiSCOG), 35128 Padova, Italy2University of Padova School of Medicine, Pathology, 35128 Padova, Italy3 S. Maria degli Angeli Hospital, Chirurgia 1, 33170 Pordenone, Italy

Background: Angiogenesis is crucial for growth of all tumors, and

mature and immature endothelial cells, such as circulating endothelial cells

(CECs) and endothelial progenitor cells, are present in the human blood.

Vasculogenesis is not restricted to embryonic development, and there are

putative circulating endothelial progenitors which can participate in the

generation of new vessels. CECs are extremely rare in normal peripheral

blood, but it has been shown that their number is significantly increased

in many pathological conditions, including cancer. Some CECs display

characteristics of terminally differentiated and mature cells, while others

express specific surface antigens, suggesting a progenitor-like or stem-

like phenotype. CECs measurement is a promising biomarker to assess

the efficacy of antiangiogenetic therapies, and their increase may suggest

the possible presence of metastatic disease, including in patients with

CRC. Different cell surface markers have been tested to detect CECs,

and flow cytometry represents a well suited method for their detection

and quantitation. The aim of this study was to evaluate the levels of the

microenvironmental cell marker CD146+CD45- phenotype, which is linked

to angiogenesis, vessel damage, and disease progression, in patients with

colorectal cancer (CRC).

Methods: Blood samples from 41 patients (26 men, 15 women, median

age 64 years, range 39-74 years) with confirmed colorectal adenocarcinoma

undergoing curative surgery were collected for analysis of CECs. Patients

with distant metastases (negative F-18 FDG PET/CT) have been excluded,

as well as those who had undergone adjuvant chemotherapy. All samples

were stained with antihuman CD146 phycoerthyrin (CD146-PE) and

CD45 fluorescein isothiocyanate (CD45-FITC). Immunophenotyping was

obtained using a Beckman Coulter XL-MCL flow cytometer to assess levels

of CD146+CD45- CECs, using a 600 s acquisition time for each sample.

Thank to final pathology, two groups of patients were obtained: Group A

(28 patients, 68.3%) with negative lymph nodes (pN0), and Group B (13 pa-

tients, 31.7%) with regional lymph node metastasis (pN1).

Results: N1 patients (Group B) had a level of CD146+/CD45- cells sig-

nificantly increased (19.2�9.1 vs. 12.4�8.6 CECs, 95% CI 0.72-12.88,

p¼0.029) in respect to N0 patients (Group B). No correlation (R¼0.10,

p¼0.22) was found between number of the N1 and level of putative

CECs. There was no differences (p¼NS) between men and women.

Conclusion: CECs are usuallyless than one in 1,000 circulating blood

cells, and their not yet completely established phenotype represent a techni-

cal challenge. However, our preliminary data suggest a possible increased

angiogenic activity in patients with N1 CRC, which can be demonstrated us-

ing flow cytometry analysis of CECs. Further endothelial cell markers, alone

or in combination, should be studied to confirm this hypothesis.

References:

Malka D et al. Ann Oncol 2011

Simkens LHI et al. Ann Oncol 2010