Copenhagen, Denmark
Onsite/Online

ESTRO 2022

Session Item

Sunday
May 08
16:55 - 17:55
Room D3
Oligometastatic disease
Joachim Widder, Austria;
Jonas Willmann, Switzerland
Proffered Papers
Clinical
17:25 - 17:35
A pREDictive model of polymetastatic disease on oligometastatic colorectal cancer: the RED LaIT-SABR
Luca Nicosia, Italy
OC-0602

Abstract

A pREDictive model of polymetastatic disease on oligometastatic colorectal cancer: the RED LaIT-SABR
Authors:

Luca Nicosia1, Davide Franceschini2, Francesca Perrone Congedi3, Franco Casamassima4, Marianna Alessandra Gerardi5, Michele Rigo1, Rosario Mazzola1, Marco Perna6, Vieri Scotti7, Andrei Fodor8, Aurelia Iurato9, Francesco Pasqualetti10, Giovanni Gadducci10, Silvia Chiesa11, Rita Marina Niespolo12, Alessio Bruni13, Giulia Alicino13, Luca Frassinelli13, Paolo Borghetti14, Alessandro Di Marzo15, Andrea Ravasio16, Berardino De Bari17, Matteo Sepulcri18, Dario Aiello19, Gianluca Mortellaro20, Claudia Sangalli21, Marzia Franceschini21, Giampaolo Montesi22, Francesco Maria Aquilanti23, Gianluigi Lunardi24, Riccardo Valdagni21, Ivan Fazio19, Luigi Corti25, Vittorio Vavassori26, Ernesto Maranzano27, Stefano Maria Magrini14, Stefano Arcangeli13, Vincenzo Valentini11, Fabiola Paiar10, Sara Ramella9, Nadia Gisella Di Muzio8, Lorenzo Livi6, Barbara Alicja Jereczek-Fossa5, Mattia Falchetto Osti3, Marta Scorsetti28, Filippo Alongi29

1IRCCS Sacro Cuore Don Calabria Hospital, Cancer Care Center, Advanced Radiation Oncology Department, Negrar, Italy; 2IRCCS Humanitas Research Hospital, Radiation Oncology Department, Milan, Italy; 3"Sapienza" University, Sant'Andrea Hospital, Department of Radiation Oncology, Rome, Italy; 4Ecomedica Radioterapia, Radioterapia, Empoli, Italy; 5IEO European Institute of Oncology IRCCS, Division of Radiation Oncology, Milan, Italy; 6Azienda Ospedaliera Universitaria Careggi, University of Florence, Radiation Oncology Unit, Florence, Italy; 7Azienda Ospedaliera Universitaria Careggi, University of Florenc, Radiation Oncology Unit, Florence, Italy; 8IRCCS San Raffaele Scientific Institute, Department of Radiation Oncology, Milan, Italy; 9Campus Bio-Medico University, Radiation Oncology, Rome, Italy; 10Pisa University Hospital, Radiation Oncology Unit, Pisa, Italy; 11Dipartimento Diagnostica per Immagini, Radioterapia Oncologica ed Ematologia, Fondazione Policlinico Universitario A. Gemelli IRCCS, UOC di Radioterapia Oncologica, Rome, Italy; 12Azienda Ospedaliera S. Gerardo, Department of Radiation Oncology, Monza, Italy; 13University Hospital of Modena, Radiotherapy Unit, Modena, Italy; 14ASST Spedali Civili di Brescia - Brescia University, Radiation Oncology Department, Brescia, Italy; 15S. Maria Hospital, Terni, Radiation Oncology Centre, Terni, Italy; 16Humanitas Gavazzeni, Bergamo, Radiotherapy Unit, Bergamo, Italy; 17University Hospital of Besançon, Besançon, Radiation Oncology Department, Besançon, France; 18Veneto Institute of Oncology IOV-IRCCS, Padua, Radiation Oncology Unit, Padua, Italy; 19Casa di Cura Macchiarella, Radiotherapy Unit, Palermo, Italy; 20ARNAS Ospedale Civico, Department of Radiation Oncology, Palermo, Italy; 21Fondazione IRCCS Istituto Nazionale dei Tumori, Department of Radiation Oncology 1, Milan, Italy; 22ULSS5, Radiotherapy Unit , Rovigo, Italy; 23Marrelli Hospital, Radiotherapy Marrelli Hospital, Crotone, Italy; 24IRCCS Sacro Cuore Don Calabria Hospital, Medical Analysis Laboratory, Negrar, Italy; 25Veneto Institute of Oncology IOV-IRCCS, Radiation Oncology Unit, Padua, Italy; 26Humanitas Gavazzeni, Radiotherapy Unit, Bergamo, Italy; 27S. Maria Hospital, Radiation Oncology Centre, Terni, Italy; 28IRCCS Humanitas Research Hospital, Radiotherapy, Milan, Italy; 29IRCCS Sacro Cuore Don Calabria Hospital, Advanced Radiation Oncology Department, Negrar, Italy

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Purpose or Objective

Aim: stereotactic ablative radiotherapy (SABR) has been shown to increase survival in oligometastatic patients. Few studies actually depicted the oligometastatic disease (OMD) evolution after SABR. There is few evidence on which patient will remain disease-free after SABR and which will develop rapidly a polymetastatic disease (PMD) therefore apart from the number of active metastases, there are no clues on which proven factor should be taken into account for prescribing local treatment in OMD. The aim of the present preliminary study based on a large retrospective database is to identify predictive factors of polymetastatic evolution in lung oligometastatic colorectal cancer patients to tailor SABR prescription.

Material and Methods

Methods: the study involved 23 centers, and was approved by the Ethical Committee (Prot. Negrar 2019-ZT). The data of 367 lung oligometastatic patients were reported. Primary end-point was the time to the polymetastatic conversion (tPMC), defined as the first occurrence of >5 simultaneous new metastases after SABR. Additionally, oligometastases number and cumulative gross tumor volume (GTV) were used as combined predictive factors of tPMC. Oligometastases number was stratified as 1, 2-3, and 4-5; cumulative GTV was dichotomized to the median value of 15.6 cc. The 6 groups are reported in table 1.


Table 1. group stratification for the analyzed patients



Median tPMC (months)
1 metastasis 
cumGTV <15.6 cc
35.8
1 metastasis 
cumGTV >15.6 cc
19.3
2-3 metastases
cumGTV <15.6 cc
34.1
2-3 metastases
cumGTV >15.6 cc
12
4-5 metastases
cumGTV <15.6 cc
5.6
4-5 metastases
cumGTV >15.6 cc
3.7




Results

Results: the median tPMC in the overall population was 26.1 months. The median tPMC stratified for the 6 groups is reported in table 1 (p=0.00). After data checking we were able to classify patients according to their median tPMC in 4 risk classes: low risk (group 1+3), favorable intermediate (group 2), unfavorable intermediate (group 4), high risk (group 5+6). The median tPMC for the 4 risk classes was: 34.6, 19.3, 12, and 6.7 months, respectively (figure 1; p=0.00).


Figure 1. tPMC stratified for risk classes

Conclusion

Conclusion: the present study identified predictive factors of polymetastatic evolution after SABR in lung oligometastatic colorectal cancer. The results demonstrated that the sole numerical number is not enough to define the OMD since patients identified as oligometastatic from a numerical point of view might rapidly progress to the PMD when the cumulative tumor volume is high. A tailored approach in SABR prescription should be pursued considering the expected disease evolution after SABR, with the aim to avoid unnecessary treatment and side effect in those at high risk of polymetastatic spread, and maximize local treatment in those with a favorable disease evolution.