[Undifferentiated small cell carcinoma and diffuse endocrine system (author's transl)]

Area of Science:

• Pulmonary Medicine
• Endocrinology
• Oncology

Background:

• Oat cell lung carcinoma (OCLC) is often linked to endocrine secretion.
• Syndromes associated with OCLC were historically termed 'paraneoplastic'.

Purpose of the Study:

• To investigate the origin of endocrine secretion in oat cell lung carcinomas.
• To clarify the relationship between tumor secretory activity and associated syndromes.
• To explore the histogenesis of oat cell carcinomas.

Main Methods:

• Electron microscopy was used to study tumor cells.
• Immunofluorescence studies were conducted.
• A review of histogenetic hypotheses and extra-pulmonary cases was performed.

Main Results:

• Endocrine secretion in OCLC is directly attributable to the tumoral cells' activity.
• Electron microscopy and immunofluorescence confirmed cellular secretory function.
• The diffuse endocrine system in the bronchial tree is identified as the origin of carcinoid and oat cell carcinomas.

Conclusions:

• The endocrine syndromes associated with oat cell lung cancer result from tumor cell secretion, not paraneoplastic phenomena.
• Oat cell carcinomas and carcinoid tumors arise from the bronchial tree's diffuse endocrine system.
• The study also briefly considers alternative histogenetic origins and extra-pulmonary manifestations.