ESTRO 36 Abstract Book

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S344 ESTRO 36 2017
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PO-0665 The role of post-mastectomy radiotherapy
(PMRT) and prognostic factors of locoregional
recurrence
D. Delishaj1, S. Ursino1 , V. Mazzotti1, L.R. Fatigante1, S.
Spagnesi1, B. Manfredi1, A. Cristaudo-1, F. Pasqualetti1,
A. Sainato 1, C. Laliscia1, M. Pnichi1, F. Orlandi 1, F.
Matteucci1, R. Morganti2, E. Lombardo1, M. Cantarella 1,
D. Baldaccini1, A. Gonnelli1, M.G. Fabrini1, A. Molinari1,
M. Roncella3, A. Falcone4, D. Caramella5, F. Paiar1
1 Azienda Ospedaliero Universitaria Pisana, Radiotherapy,
Pisa, Italy
2 Azienda Ospedaliero Universitaria Pisana, Section of
Statistics, Pisa, Italy
3 Azienda Ospedaliero Universitaria Pisana, Breast
Surgery, Pisa, Italy
4 Azienda Ospedaliero Universitaria Pisana, Oncology,
Pisa, Italy
5 Azienda Ospedaliero Universitaria Pisana, Radiology,
Pisa, Italy
Purpose or Objective
The purpose of the study was to evaluate the outcome of
patients (pts) undergone to mastectomy followed or not
by post-mastectomy radiotherapy (PMRT) and to
investigate the clinicopathological prognostic factors of
locoregional recurrence (LRR).
Material and Methods
We retrospectively reviewed data of patients underwent
total mastectomy and sentinel lymph node examination
+/- axillary dissection. Patients were staged according to
AJCCU/UICC 7° Edition.
According to consensus in literature PMRT was limited to
the chest wall (CW-PMRT) in stage pT3 N1 or extended to
the lymphatic drainages of apex axilla and supraclavicular
nodes (CWLD-PMRT) in stage pT4 N2-3. Patients
underwent salvage mastectomy after a previous
conservative surgery and RT or with of systemic disease at
diagnosis were excluded from the study.
Radiotherapy treatment was performed with linear
accelerator and 3DCRT technique using X photons of 6
and/or 15 MV energy. Two tangential beam technique was
used for CW-PMRT whereas an half beam technique with
the addiction of 1-2 anterior-posterior (AP-PA) beam was
used for CWLD-PMRT. The prescribed dose was 50 Gy
delivered in 25 fractions adding a boost of 20 Gy and 14-
16 Gy for positive and close (<2mm) surgical margins,
respectively.
Neoadjuvant chemotherapy (CT), adjuvant CT,
Trastuzumab, Tamoxifen and systemic endocrine therapy
were prescribed according to international guidelines.
Radiotherapy was deferred after the completion of
adjuvant CT. Univariate and multivariate analyses were
performed using SPSS 22 (SPSS Inc., Chicago, IL, USA)
technology.
Results
Between January 2004 and June 2013 a total of 912
patients underwent to total mastectomy; of whom 269
(29,5%) underwent to PMRT and 643 (70,5%) not. Among
PMRT group 77 underwent to CW and 202 to CWLD
irradiation. The median follow up was 40 months (range,
3-118). No significant difference in terms of LRR was found
between the no-PMRT and PMRT group (p=0,175;
HR=1,613; CI95%=0,808-3,219).
The uni and multivariate analysis of LRR for patients not
undergone to PMRT showed a significant correlation with
the presence of ECE (p=0,049), Mib-1 >30% (p=0,048) and
triple negative status (p=0,001). On the contrary, the
triple negative status resulted as the only variable
significantly correlated to LRR (p<0,0001) in the PMRT
group whereas ECE and Mib-1>30% lost the
significance. Finally, no significant difference was shown
between CWLD and CW-PMRT (p=0,078; HR=0,375; CI95%=
0,126-1,116).
Conclusion
Based on our data, we strongly confirm the positive impact
of PMRT in local advance disease and recommend to
carefully consider it in presence of ECE and Mib-1>30%
regardless T and N stage. CW irradiation might be a valid
option in selected intermediate disease (i.e. less than 3
positive lymph nodes). Future “well designed”
prospective studies are needed to properly validate our
results.
Poster: Clinical track: Lung
PO-0666 30 Gy single-dose SBRT to lung lesions:
outcome in a large series of patients
L. Nicosia1, C. Reverberi1, L. Agolli1, M. Valeriani1, V. De
Sanctis1, C. De Dominicis2, G. Minniti 1, E. Cortesi3, M.
Martelli4, M.F. Osti1
1Sant’Andrea Hospital- University of Rome "Sapienza",
Radiation Oncology, Rome, Italy
2Sant’Andrea Hospital- University of Rome “Sapienza”,
Department of Radiology, Rome, Italy
3Policlinico Umberto I- University of Rome “Sapienza”,
Department of Radiology- Oncology and Human
Pathology, Rome, Italy
4Carlo Forlanini Hospital- Rome- Italy, Thoracic Surgery
Unit, Rome, Italy
Purpose or Objective
We conducted a prospective study to evaluate the
effectiveness, safety and toxicity of a Stereotactic Body