CASE PRESENTATION
A six-year-old girl was admitted to a general hospital with fever, persistent cough and dyspnea. No episodes of recurrent respiratory infections were reported. Blood tests revealed only an increase of C-reactive protein 9.67 mg/dl (range 0-0.5), Chest X-ray showed a bilateral pneumonia. Oxygen therapy plus antibiotic therapy and steroids were started without any improvement and needing for invasive respiratory support
A Computed Tomography (CT) scan confirmed multiple pulmonary consolidations on both lobes. COVID molecular nasopharyngeal test was negative. MA solid-like parietal protrusion floating in the tracheal lumen (approximately 12x8 mm) was detected. All microbiological tests were negative. Diagnostic work-up included a fibroscopy with bronchiolar-alveolar washing and biopsy of the endotracheal mass. Patient was referred to our hospital.
The pathology revealed an ulcerated mucosa with an underlying proliferation of bland spindle to stellate-shaped cells in a myxoid stroma associated with a mild inflammatory infiltrate including lymphocytes, scattered plasma cells and histiocytes. Immunohystochemical stains showed positivity for vimentin and smooth muscle actin while ALK1, ALKp80, desmin, myogenin, cytocheratin CAM5.2, CD45, CD31, S100, EMA and MUC4 were all negative. An unbalanced rearrangement of ALK (exons 10-20), showing TRAF3-ALK fusion transcript was found. Finally, a diagnosis of IMT was rendered. The surgery was postponed considering the high risk of bleeding, mutilation and life-threatening complications. Crizotinib was started at 165 mg/mq/dose twice daily for 21 days/course with a rapid improvement and weaning from mechanical respiratory support confirmed at endotracheal fibroscopy demonstrating a partial response (fig.1). The child was discharged from pediatric intensive care unit (PICU). After two-week treatment, a new CT scan showed a 70% reduction of the mass achieving the best response after 4 weeks from Crizotinib. No mild or severe treatment side effect were observed.
At the time of the last follow-up, after eight months of therapy, she is still on treatment. The patient is in good condition and achieved a complete response (fig 2).