A 52-year-old woman presents with a 1-year history of upper truncal obesity and moderate depression. Physical examination shows hirsutism and moon facies. A CT scan of the thorax displays a hilar mass. A transbronchial lung biopsy discloses small cell carcinoma. Electron microscopy of this patient's lung tumor will most likely reveal which of the following cytologic features?

Neuroendocrine tumors may synthesize a number of hormones. The presence of small, membrane-bound granules with a dense core is a feature of these neoplasms. Dense granules are visible by electron microscopy. Carcinomas often exhibit desmosomes and specialized junctional complexes, which are structures that are not typical of sarcomas or lymphomas. Councilman bodies (choice A) are apoptotic hepatocytes (acidophilic bodies).