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Conclusion
18
FDG-PET is able to define active bone marrow within
pelvic osseous structures.
ACT
BM is a predictor
of decreased blood cells nadirs in anal cancer patients
undergoing concurrent chemo-radiation. Lumbar-sacral
bone marrow dose seems to be the strongest predictor.
PV-0325 Tumor Regression Grading in the
CAO/ARO/AIO-04 phase 3 trial in locally advanced
rectal carcinoma
E. Fokas
1
, M. Ghadimi
2
, R. Fietkau
3
, P. Ströbel
4
, A.
Hartmann
5
, R. Sauer
6
, T. Liersch
2
, T. Hothorn
7
, C.
Wittekind
8
, C. Rödel
1
1
Goethe University Frankfurt, Department of
Radiotherapy and Oncology, Frankfurt, Germany
2
University of Göttingen, Department of General-
Visceral and Pediatric Surgery, Göttingen, Germany
3
University of Erlangen, Department of Radiation
Oncology, Erlangen, Germany
4
University of Göttingen, Deparment of Pathology,
Göttingen, Germany
5
University of Erlangen, Deparment of Pathology,
Erlangen, Germany
6
University of Erlangen, Deparment of Radiation
Oncology, Erlangen, Germany
7
University of Zurich, Epidemiology- Biostatistics and
Prevention Institute, Zurich, Switzerland
8
University of Leipzig, Institute of Pathology, Leipzig,
Germany
Purpose or Objective
We examined the prognostic value of tumor regression
grading (TRG) in 1208 patients with locally advanced
rectal carcinoma treated within the CAO/ARO/AIO-04 trial
after a median follow-up of 50 months.
Material and Methods
TRG and clinicopathologic parameters were correlated to
clinical outcome. Statistical differences between groups
were calculated by the Log-rank test, and incidence
curves were plotted using the Kaplan-Meier method. The
Cox regression and the Fine-Gray models were used for the
multivariate analysis. We used the four Prentice criteria
(PC1-4) to assess the surrogacy of TRG for disease-free
survival (DFS).
Results
The 3-year cumulative incidence of DFS, distant
metastases, local recurrence and overall survival (OS)
were 64.6%, 25.4%, 6.9% and 76.8% for patients with TRG
0+1 (poor regression), 77.6%, 18.3%, 3.3% and 89.2% for
TRG 2 + 3 (intermediate regression), and 92.3%, 4.1%, 0%
and 96.2% for TRG 4 (complete regression), respectively
(P < .001, for all four endpoints). Due to multicollinearity,
TRG 4 and pathologic stage was not assessed within the
same model. TRG 2+3 vs TRG 0+1 after preoperative CRT
remained an independent prognostic factor for DFS (HR,
0.677; P = .007), the cumulative incidence of local
recurrence (HR, 0.504; P = .028) and OS (HR, 0.582; P <
.001). Notably, TRG satisfied PC1-3 for individual-level
surrogacy (P = .037, P < .001 and P < .001, respectively).
The treatment effect on DFS was captured by TRG and
therefore PC4 satisfaction is plausible.
Conclusion
TRG following preoperative chemoradiotherapy predicted
for a favorable long-term outcome in multivariate
analysis. In the era of personalized medicine. TRG might
constitute an attractive option to validate molecular
biomarkers, facilitate successful clinical testing of new
biological agents and tailor treatment-adaptive strategies
based on initial response in early phase trials in the era of
personalized medicine. Further examination and
validation of TRG as surrogate for DFS based on large
independent phase III trials is needed and should be
enhanced for its implementation in the regular pathologic
work-up.
PV-0326 Time to surgery and pCR after neoadjuvant
CRT in rectal cancer: a population study on 2113
patients
G. Macchia
1
, M. Gambacorta
2
, G. Chiloiro
2
, G. Mantello
3
,
A. De Paoli
4
, G. Montesi
5
, A. Sainato
6
, M. Lupattelli
7
, L.
Caravatta
8
, F. Perrotti
9
, M. Rosetto
10
, F. Filippone
11
, R.
Niespolo
12
, M. Osti
13
, L. Belgioia
14
, C. Boso
15
, A.
Fontana
16
, S. Parisi
17
, A. Galardi
18
, L. Turri
19
, P.
Sciacero
20
, L. Giaccherini
21
, C. Masciocchi
2
, A. Morganti
21
,
V. Valentini
2
1
Fondazione di Ricerca e Cura “Giovanni Paolo II,
Radiotherapy Unit, Campobasso, Italy
2
Fondazione “Policlinico Gemelli”- Università Cattolica
S. Cuore, Department of Radiotherapy, Roma, Italy
3
Azienda Ospedaliero Universitaria- Ospedali Riuniti,
Radiotherapy Unit, Ancona, Italy
4
Oncological Referral Center, Radiation Oncology
Department, Aviano, Italy
5
ULSS18, Radiotherapy Unit, Rovigo, Italy
6
University Hospital, Radiotherapy Unit, Pisa, Italy
7
'S. Maria della Misericordia' Hospital, Radiotherapy
Unit, Perugia, Italy
8
'A. Businco' Regional Oncological Hospital, Radiation
Oncology Department, Cagliari, Italy
9
'SS Annunziata' Hospital- 'G. D'Annunzio' University,
Radiotherapy Unit, Chieti, Italy
10
Ospedale Belcolle, Radiotherapy Unit, Viterbo, Italy
11
Azienda ospedaliera Papa Giovanni XXIII, Radiotherapy
Unit, Bergamo, Italy
12
Azienda Ospedaliera S. Gerardo-, Radiotherapy Unit,
Monza, Italy
13
Facoltà di Medicina e Psicologia- Università Sapienza,
Department of Radiation Oncology, Roma, Iceland
14
AOU IRCCS San Martino- IST National Cancer Research
Institute, Radiotherapy Unit, Genova, Italy
15
Veneto Institute of Oncology-IRCCS, Radiotherapy and
Nuclear Medicine Unit, Padova, Italy
16
Ospedale S.M. Goretti, Radiotherapy Unit, Latina, Italy
17
Casa Sollievo della Sofferenza- IRCCS-CSS,
Radiotherapy Unit, San Giovanni Rotondo, Italy
18
Florence University, Department of Radiotherapy,
Firenze, Italy
19
'Maggiore della Carità' Hospital, Radiotherapy Unit,
Novara, Italy
20
ASL TO4- General Hospital, Radiotherapy Unit, Ivrea,
Italy
21
Policlinico Universitario S. Orsola Malpighi,
Radiotherapy, Bologna, Italy
Purpose or Objective
Population based electronic health records, provide a
means of obtaining information on patient characteristics
and outcomes that can then be compared with the more
selected populations recruited within randomized
controlled trials. Aim of this analysis was to
retrospectively evaluate the difference in terms of
pathologic complete response (pCR) according to time
elapsed between chemoradiation (CRT) and surgery on a
large unselected real-life dataset of locally advanced
rectal cancer (LARC) patients.
Material and Methods
A multicentre retrospective cohort study of LARC patients
among 21 Italian Radiotherapy Institutions was performed.
3D conformal or intensity-modulated radiation treatment
was required as inclusion criteria. Surgery was performed
according to the principles of total mesorectal excision
(TME). Patients were stratified according to 3 different