Persistence of Elevated Procalcitonin in a Patient with Coronavirus Disease 2019 Uncovered a Diagnosis of Medullary Thyroid Carcinoma oleh Laura Gianotti, MD, PhD, Salvatore D’Agnano, MD, Giorgio Pettiti, MD, Francesco Tassone, MD, Giorgio Giraudo, MD, Corrado Lauro, MD, Giuseppe Lauria, MD, Valerio Del Bono, MD, Giorgio Borretta, MD