From the Guidelines
Yes, adenoid cystic carcinoma (ACC) of the salivary glands can metastasize to the hilar lymph nodes, though this is not the most common pattern of spread for this cancer. ACC typically has a propensity for perineural invasion and hematogenous spread rather than lymphatic metastasis, as noted in the management guidelines for salivary gland malignancy 1. When ACC does spread to lymph nodes, it more commonly affects cervical lymph nodes first due to their proximity to the salivary glands. Hilar lymph node involvement usually occurs as part of distant metastasis, particularly when the cancer has already spread to the lungs, which is the most common site of distant metastasis for ACC, affecting up to 90% of cases with distant metastases 1.
The overall pattern of spread for ACC, including its tendency for late recurrence and distant metastasis, reflects its biological behavior as a slow-growing but persistent malignancy. Key considerations in managing ACC include regular follow-up with surveillance imaging, given that delayed diagnosis of tumor recurrence can lead to a poor prognosis and decreased long-term survival 1. The most recent guidelines recommend yearly chest CT scans for surveillance, especially in cases of advanced-stage malignancy or high-grade histopathology, due to the high frequency of pulmonary metastases in ACC 1.
Given the potential for ACC to metastasize to various sites, including the lungs and subsequently to hilar lymph nodes, a comprehensive approach to surveillance and follow-up is crucial. This approach should be tailored to the individual patient's risk factors, histopathology, and disease stage, emphasizing the importance of early detection and management of recurrence or metastasis to improve outcomes in terms of morbidity, mortality, and quality of life.
From the Research
Metastasis of Adenoid Cystic Carcinoma (ACC) to Hilar Lymph Nodes
- The provided studies do not specifically mention metastasis of adenoid cystic carcinoma (ACC) to the hilar lymph nodes 2, 3, 4, 5, 6.
- However, it is noted that ACC tends to metastasize to distant sites, with the lungs being a common location 2, 3, 5.
- The lungs are a primary site for metastasis, and given their proximity to the hilar lymph nodes, it is plausible that metastasis could occur in these nodes, although this is not explicitly stated in the provided studies.
- Regional lymph node metastases, including potentially those in the hilar region, are less common than distant metastases in ACC patients 3, 5.
- The studies focus more on the metastasis patterns to organs like the lungs, bones, liver, and brain, rather than specifically to lymph nodes like those found in the hilar region 2, 3, 4, 5, 6.