A 55-year-old man underwent wide excision of an adenoid cystic carcinoma of the hard palate two years ago with clear margins. He now presents with dry cough and exertional dyspnea. Chest CT shows multiple well-defined peripheral nodules. Which biological behavior of this tumor best explains this presentation?

• A Predilection for early regional lymph node metastasis
• B Surface epithelial seeding causing tracheobronchial papillomatosis
• C Obligate transformation to small cell carcinoma
• D Hematogenous dissemination with late pulmonary metastasis despite slow growth ✓

Explanation

Adenoid cystic carcinoma grows slowly, recurs over decades, spreads predominantly by perineural infiltration, and metastasizes hematogenously, most often to lung, sometimes many years after controlling the primary. Regional nodal spread is distinctly uncommon, seen in fewer than 10 percent of cases, which kills option A. Long-term follow-up is mandatory because late pulmonary relapse is characteristic.

Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.