Problemi speciali
Timo ectopico: quando pensarci, la diagnosi per immagini, la gestione
Ectopic thymus: when tothink about it, its imaging diagnosis and management
Riccardo Bisi1,2, Angela Troisi3, Diana Wrona3,4, Federico Marchetti3, Giancarlo Parenti2
1Scuola di Specializzazione in Radiodiagnostica, Università di Ferrara
2UOC di Radiodiagnostica, 3UOC di Pediatria e Neonatologia, Ospedale di Ravenna, AUSL della Romagna
4Scuola di Specializzazione in Pediatria, Università di Bologna
Dicembre 2023 - pagg. 631 -636 | DOI: 10.53126/MEB42631
Abstract
Ectopic thymic tissue is a rare occurrence in clinical practice. However, it could cause diagnostic difficulties, especially in the paediatric age group, as it can mimic a cervical mass. In most cases, thymic ectopia is asymptomatic and the ectopic thymic tissue presents as a painless cervical mass. It could rarely cause stridor, dyspnoea, dysphonia and dysphagia. Ultrasound is the first-level diagnostic investigation. Only in doubtful cases, magnetic resonance imaging is almost always diagnostic, as the ectopic tissue shows signal intensity comparable to the normal thymus. The fine-needle aspiration may be avoided and conservative treatment may be performed through ultrasound follow-up. Surgical excision is reserved when imaging and biopsy are still inconclusive or in the presence of symptoms. The paper presents a clinical case of asymptomatic cervical ectopic thymus in a healthy girl, suspected on ultrasound examination and confirmed on magnetic resonance imaging.
Riassunto
Il riscontro di tessuto timico ectopico è un’eventualità relativamente rara nella pratica clinica, ma può essere potenzialmente causa di difficoltà diagnostiche, specie nella fascia d’età pediatrica, potendo mimare una massa cervicale. Nella maggior parte dei casi l’ectopia timica è asintomatica e si presenta come una massa cervicale indolente; molto raramente, per effetto massa, può causare stridore, dispnea, disfonia, disfagia. L’ecografia rappresenta l’indagine diagnostica di primo livello. Solo nei casi dubbi la risonanza magnetica risulta quasi sempre diagnostica, in quanto il tessuto mostra caratteristiche di intensità del tutto sovrapponibili al timo normale. Il ricorso alla biopsia con ago sottile è divenuto meno frequente e il trattamento deve essere conservativo mediante follow-up ecografico. L’asportazione chirurgica è indicata solo nei casi dubbi, anche dopo imaging ed eventuale biopsia, o nei casi sintomatici. Presentiamo un caso clinico di timo ectopico cervicale asintomatico in una ragazza sana, sospettato all’esame ecografico e confermato alla risonanza magnetica.
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Corrispondenza: angela.troisi@auslromagna.it