ESTRO 36 Abstract Book

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S677 ESTRO 36 2017
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REFERENCES:
1. Vuong et al. Contribution of conformal therapy in the
treatment of anal canal carcinoma with combined
chemotherapy and radiotherapy: Results of a phase II
study. Int J Radiat Oncol Biol Phys 2003; 56(3): 823-31.
EP-1272 Impact of Ki67 on pathological complete
response rate after neoadjuvant CRT in cT3N0M0 rectal
cancer
D. Adua1, L. Giaccherini2, A. Guido2, D. Cuicchi3, F. Di
Fabio1, F.L. Rojas Llimpe 1, G. Macchia4, S. Cammelli2, L.
Fuccio3, A. Ardizzoni1, A.G. Morganti2
1 S.Orsola-Malpighi Hospital, Department of Medical
Oncology, Bologna, Italy
2 University of Bologna, Radiation Oncology Unit-
Department of Experimental- Diagnostic and Specialty
Medicine - DIMES- Sant'Orsola-Malpighi Hospital,
Bologna, Italy
3 University of Bologna, Department of Medical and
Surgical Sciences - DIMEC, Bologna, Italy
4 Fondazione di Ricerca e Cura Giovanni Paolo II-
Università Cattolica del Sacro Cuore, Radiotherapy Unit,
Campobasso, Italy
Purpose or Objective
Multimodal therapeutic approach with pre-operative
chemoradiation (CRT), conservative surgery +/- adjuvant
chemotherapy (CT) is currently the standard treatment in
patients with locally advanced rectal ca. The possibility to
predict tumor response before chemoradiation could be
useful to tailor neoadjuvant treatment. Therefore, aim of
this analysis was to correlate the expression of Ki67 with
pathological complete response (pCR) rate after CRT in an
homogeneous population of patients with cT3N0M0 rectal
carcinoma.
Material and Methods
We retrospectively analysed the pre-treatment biopsies of
a subgroup of patients (pts) witch cT3N 0 rectal ca.
The expression of Ki-67 was evaluated. Radiotherapy was
delivered with 3-D conformal technique (total dose: 50.4
Gy, 1.8 Gy/fraction) concurrently with CT (Capecitabine:
31%, 5-Fluorouracil: 17%, 5-Fluorouracil plus Oxaliplatin:
52%). All pts underwent surgery 6-8 weeks after CRT.
Adjuvant CT was performed in 37 (76%) pts. DFS and OS
were estimated by Kaplan-Meier method. Using as cut-off
value the median value of ki-67 expression (91.3%, range
54.1%-99.9%), we stratified pts into two subgroups to test
a possible correlation with pCR.
Results
Forty-eight pts were treated from March 2002 to October
2011 [M/F: 32/16; median age: 70.5, range: 43-84]. The
median follow-up was 61.5 months (range: 2-136). Ten pts
achieved a pCR (20.8%). No significant differences were
observed based on Ki67 value (lower Ki67: 62.5% pCR;
higher Ki67: 37.5% pCR); Fisher's Exact test: p=0.345).
One-year, 3-year, and 5-year cumulative DFS were 97.9%,
86.0%, and 79.8%, respectively. One-year, 3-year, and 5-
year cumulative OS were 97.8%, 93.5%, and 84.1%,
respectively (fig.1).
Conclusion
In this retrospective analysis no significant correlation was
observed between Ki67 expression and pCR rate after
preoperative chemoradiation. The small sample size and
heterogeneity in neoadjuvant and adjuvant treatment
could explain this result.
EP-1273 Stereotactic body radiation therapy (SBRT)
for pelvic re-irradiation
Y. Augustin1, C. Chaw1, N. Van As1, K. Aitken1
1Royal Marsden Hospital Trust & Institute of Cancer
Research, Radiotherapy, London, United Kingdom
Purpose or Objective
Re-irradiation of recurrent pelvic disease remains a
challenging clinical problem. SBRT is an attractive
modality for re-irradiation which is being increasingly
utilised in carefully selected patients. However there
remains uncertainty around clinical toxicity, efficacy and
maximum safe cumulative doses to pelvic organs at risk
(OARs).
The primary aim of this retrospective study was to
evaluate treatment related toxicity in patients receiving
SBRT with the Cyberknife platform for pelvic re-irradiation
at our institution. Secondary objectives were to evaluate
efficacy by analysis of local control (LC), distant
progression free survival (DPFS) and overall survival (OS)
parameters.
Material and Methods
Patients receiving re-irradiation with SBRT to pelvic
targets within a previously irradiated external beam
radiotherapy (EBRT) field were retrospectively identified.
Patients treated with prior pelvic brachytherapy were
excluded. Details on primary site, previous EBRT and re-
irradiation dose, toxicity, local control and survival were
obtained on review of the hospital records. Acute (≤3
months) and late toxicity data were retrospectively
collected and assessed using CTCAE v4.0. Local and distant
progression free survival were calculated from the date of
SBRT to the date of radiological progression using standard
RECIST criteria (v1.1).
Results