Clinical features, treatment and outcomes in patients with tracheal adenoid cystic carcinoma: a systematic literature review

BACKGROUND: Primary tracheal adenoid cystic carcinoma (TACC) is rare and originates from the minor salivary gland. Biologically, TACC results in delayed presentation, and the therapeutic effects of multimodal treatment differ across individuals. This study aimed to review cases of TACC to identify clinical features, imaging modalities, treatment, and patient outcomes across follow-ups. METHODS: The PubMed, Web of Science and MEDLINE databases were searched to identify articles reporting cases of TACC. The study variables included in the analysis were patient demographics, biological characteristics, presenting symptoms, imaging modalities, treatments, follow-up times and survival outcomes. RESULTS: A total of 76 articles and 1252 cases were included in this review. The most common presenting symptom was dyspnoea (86.0%), followed by cough (58.0%). Surgery alone (40.9%), surgery with postoperative radiotherapy (36.4%) and radiotherapy alone (19.2%) were used most frequently treatments modalities. Of the 1129 cases with disease control and survival data, there was no evidence of disease in 78.7%, local recurrence was reported in 3.8%. Distant metastasis rate was 24.9% of 418 reported cases, lung (44.2%) was the most commonly involved organ. The 5, 10 years survival rate of patients treated with surgery alone and surgery with postoperative radiotherapy were 86.4%, 55.6% and 97.3%, 44.4%, respectively. CONCLUSION: TACC most common presenting symptoms were dyspnoea, cough and shortness of breath. Surgery alone and surgery with postoperative radiotherapy are predominant treatment modalities. Both seems to provide a good result in term of disease control and long-term survival rate in patients with TACC.