Table of Contents Table of Contents
Previous Page  632 / 1023 Next Page
Information
Show Menu
Previous Page 632 / 1023 Next Page
Page Background

ESTRO 35 2016 S605

________________________________________________________________________________

EP-1286

Does dose-escalated neo-adjuvant radiotherapy improve

pathological response in rectal cancers?

N. Pasha

1

Queen's Hospital, Clinical Oncology, Romford, United

Kingdom

1

, D. Woolf

1

, M. Martinou

1

, K. Williams

1

, S. Ball

1

, S.

Raouf

1

Purpose or Objective:

Neoadjuvant chemoradiotherapy

(CRT) is considered a standard approach for locally invasive

rectal cancer. Several phase 3 studies have shown an

improvement in local control with combined radiotherapy

and capecitabine / 5-fluorouracil. There is good evidence

that increased dose of radiotherapy is associated with both

better pathological response and survival in many

malignancies, although the data in rectal cancer is less

convincing. In this study we assessed the impact of dose-

escalated radiotherapy on pathological outcome.

Material and Methods:

We evaluated all patients who

received chemo-radiotherapy for rectal cancer and

subsequently had an anterior resection/ abdominoperineal

resection with a total mesorectal excision (TME) between

February 2012 and December 2014. Patients received 50.4Gy

1.8Gy fractions, and more recently those who have T3/4

disease with a threatened circumferential margin had a

simultaneous integrated boost of the primary tumour to a

total dose of 53.2Gy, with concurrent capecitabine

chemotherapy (825mg/m2 BD) daily throughout treatment.

Treatment was initially using 3-D conformal radiotherapy but

more recently has been using a VMAT technique with cone

beam CT used during treatment. Surgery was performed 8-12

weeks after completion of CRT.The primary end point was

pathological response (Dworak score 0-4) of the operative

specimen. Scores of 0-2 were considered to be non-

pathological responders and scores of 3-4 were considered to

be pathological responders.

Results:

A total of 73 patients received neoadjuvant

chemoradiotherapy. 61 patients weretreated with a standard

radiotherapy fractionation of 50.4Gy in 28 fractions (Group A)

and 12 patients were treated with a dose escalated

fractionation to the primary tumour of 53.2Gy in 28 fractions

(Group B). The rate of pathological response was 39.3% in

Group A and 86.7% with Group B (t=3.55, p<0.001).

Conclusion:

This study demonstrates the beneficial effects of

dose-escalated radiotherapy and wetherefore recommend

this regime be considered for inclusion in future phase 2

studies.

EP-1287

Radiation-induced rectal toxicity in prostate cancer: a

proctoscopy evaluation

E. Ippolito

1

Campus Biomedico University, Radiotherapy Unit, Roma,

Italy

1

, M. Nuzzo

2

, G. Macchia

2

, F. Deodato

2

, S. Cilla

3

, M.

Ingrosso

4

, L. Fuccio

5

, A. Farioli

5

, G. Mantini

6

, V. Valentini

6

,

G.C. Mattiucci

6

, G. Siepe

7

, M. Ntreta

7

, S. Cammelli

7

, A.

Guido

7

, M. Pieri

7

, A. Arcelli

7

, F. Bertini

7

, L. Ronchi

7

, A.G.

Morganti

7

2

Fondazione di Ricerca e Cura “Giovanni Paolo II”- Catholic

University of Sacred Heart, Radiotherapy Unit, Campobasso,

Italy

3

Fondazione di Ricerca e Cura “Giovanni Paolo II”- Catholic

University of Sacred Heart, Medical Physics Unit,

Campobasso, Italy

4

Fondazione di Ricerca e Cura “Giovanni Paolo II”- Catholic

University of Sacred Heart, Endoscopy Unit, Campobasso,

Italy

5

Sant’Orsola-Malpighi Hospital- University of Bologna,

Department of Medical and Surgical Sciences - DIMEC,

Bologna, Italy

6

Policlinico Universitario “A. Gemelli”- Università Cattolica

del Sacro Cuore, Department of Radiotherapy, Roma, Italy

7

Radiation Oncology Center- Sant'Orsola-Malpighi Hospital-

University of Bologna, Department of Experimental-

Diagnostic and Specialty Medicine - DIMES, Bologna, Italy

Purpose or Objective:

Early proctoscopy (1 year) can predict

late rectal mucosa changes and therefore can be used as

surrogate end-point for late rectal toxicity. The aim of this

study was to retrospectively analyze data of patients treated

at a single institution, consecutively enrolled in different

prospective clinical trials, trying to determine a correlation

between treatment parameters and VRS (Vienna Rectoscopy

Score) recorded at 1-year proctoscopy.

Material and Methods:

Patients with prostate

adenocarcinoma treated with curative or adjuvant RT

underwent endoscopy one year after RT; 195 patients were

included in this analysis. Correlations between VRS > 2 and

several treatment parameters were investigated by

univariate and multivariate logistic analysis.

Results:

Patients treated with an EQD2 dose > 75 Gy, with

hypofractionatied schedule and radiosurgery boost had a

higher incidence of VRS > 2 (p= < 0.001). On the contrary,

previous surgery and 3D-conformal radiotherapy (vs IMRT)

were associated with a lower incidence of rectal mucosal

changes (p=< 0.001; p= 0.003, respectively). At multivariate

analysis radiosurgery boost was associated with the highest

odd ratios for the risk of developing a VRS > 2 (OR: 4.143; CI:

1.24-13.81; p=0.001). Even surgery showed a significant

correlation with VRS > 2 (OR: 0.39; CI: 0.17-9.94; p=0.037,

Table 1).

Conclusion:

Prolonged patients follow-up is needed to

“clinically” confirm the increased rectal toxicity produced by

radiosurgery boost.

EP-1288

Sphincter function and dose of radiation in rectal cancer. A

Single-Institutional study

F. Arias

1

Complejo Hospitalario de Navarra, Department of

Radiotherapy-Oncology, Pamplona, Spain

1

, C. Eito

1

, G. Asín

1

, I. Mora

1

, K. Cambra

2

, F. Mañeru

3

,

B. Ibáñez

2

, L. Arbea

4

, M. Errasti

1

, M. Barrado

1

, M. Campo

1

, I.

Visus

1

, J. García-Escobedo

1

, C. Torres

1

, M. Ciga

5

2

Complejo Hospitalario de Navarra, Statistics Department,

Pamplona, Spain

3

Complejo Hospitalario de Navarra, Department of Physics,

Pamplona, Spain

4

Clínica Universidad de Navarra, Department of

Radiotherapy-Oncology, Pamplona, Spain

5

Complejo Hospitalario de Navarra, Department of Surgery,

Pamplona, Spain

Purpose or Objective:

The objective of the study is to

determine the correlations among the variables of dose and

the sphincter function (SF) in patients with locally advanced

rectal

cancer

treated

with

preoperative

capecitabine/radiotherapy followed by Local Anterior

Resection(LAR) +TME.

Material and Methods:

We have retrospectively reviewed 92

consecutive patients with LARC treated at our center with

LAR from 2006 and more than 1 year free from disease. We

re-contoured the anal sphincters (AS) of patients with the

help of the radiologist. SF was assessed with the Wexner

scale (0-20 points, being punctuation inversely proportional

to SF). All questionnaires were filled out between January

2010 and December 2012. Dosimetric parameters that have

been studied include: V20 V30, V40, V50, mean dose

(Dmean), mínimum dose (Dmin), D90 (dose received by 90%

of the sphincter) and D98 Statistical analysis: the correlations