Received: 13 February 2017
Accepted: 25 December 2018
First Online: 7 January 2019
Ethics approval and consent to participate
: Approved by Ethics Commettee of "Seconda Università degli Studi di Napoli" Prot. 1116 -30 July 2015.We obtained written informed consent from all patients.
: “Not applicable” because in the manuscript and in the data set there aren’t individual patient data.
: All the authors declare that they have no competing interests both financial and non-financial.
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