Cytomorphology of adenocarcinoma of lung presenting as submandibular salivary gland mass: report of a case diagnosed by fine-needle aspiration biopsy.

BACKGROUND: Primary malignant neoplasms of the submandibular salivary gland (SMG) are rare, and metastatic tumors are rarer. Most of the metastases are discovered months or years after the diagnosis of the primary malignancy. Despite the increasingly used fine-needle aspiration biopsy (FNAB) in the evaluation of major salivary gland masses, diagnosis of metastases by FNAB has been only rarely studied. CASE: We report a case of lung carcinoma initially presented as a SMG swelling diagnosed by aspiration biopsy. The patient is a 52-yr-old man, a 40-pack/year smoker who also complained of weight loss and blood-streaked cough. An FNAB of the mass was consistent with metastatic adenocarcinoma with prominent signet ring-cell component of unknown primary. Subsequent studies revealed a left lung mass and left pleural effusion. The effusion cytologic examination showed malignant cells consistent with carcinoma. The patient's condition deteriorated rapidly, and he died within a few days. An autopsy revealed adenocarcinoma of lung with prominent signet ring-cell component.
CONCLUSION: FNAB is a rapid, safe, reliable, and cost-efficient technique for evaluation of major salivary glands lesions. To our knowledge, this case is the first lung carcinoma presenting as SMG mass initially diagnosed on FNAB.