Paraneoplastic Endocrine Syndromes: Syndromes resulting from inappropriate production of HORMONES or hormone-like materials by NEOPLASMS in non-endocrine tissues or not by the usual ENDOCRINE GLANDS. Such hormone outputs are called ectopic hormone (HORMONES, ECTOPIC) secretion.Paraneoplastic Syndromes: In patients with neoplastic diseases a wide variety of clinical pictures which are indirect and usually remote effects produced by tumor cell metabolites or other products.Paraneoplastic Syndromes, Nervous System: Degenerative or inflammatory conditions affecting the central or peripheral nervous system that develop in association with a systemic neoplasm without direct invasion by tumor. They may be associated with circulating antibodies that react with the affected neural tissue. (Intern Med 1996 Dec;35(12):925-9)Paraneoplastic Polyneuropathy: A diffuse or multifocal peripheral neuropathy related to the remote effects of a neoplasm, most often carcinoma or lymphoma. Pathologically, there are inflammatory changes in peripheral nerves. The most common clinical presentation is a symmetric distal mixed sensorimotor polyneuropathy. (Adams et al., Principles of Neurology, 6th ed, p1334)Paraneoplastic Cerebellar Degeneration: Cerebellar degeneration associated with a remote neoplasm. Clinical manifestations include progressive limb and GAIT ATAXIA; DYSARTHRIA; and NYSTAGMUS, PATHOLOGIC. The histologic type of the associated neoplasm is usually carcinoma or lymphoma. Pathologically the cerebellar cortex and subcortical nuclei demonstrate diffuse degenerative changes. Anti-Purkinje cell antibodies (anti-Yo) are found in the serum of approximately 50% of affected individuals. (Adams et al., Principles of Neurology, 6th ed, p686)Syndrome: A characteristic symptom complex.Limbic Encephalitis: A paraneoplastic syndrome marked by degeneration of neurons in the LIMBIC SYSTEM. Clinical features include HALLUCINATIONS, loss of EPISODIC MEMORY; ANOSMIA; AGEUSIA; TEMPORAL LOBE EPILEPSY; DEMENTIA; and affective disturbance (depression). Circulating anti-neuronal antibodies (e.g., anti-Hu; anti-Yo; anti-Ri; and anti-Ma2) and small cell lung carcinomas or testicular carcinoma are frequently associated with this syndrome.Paraneoplastic Syndromes, Ocular: Ocular manifestations secondary to various NEOPLASMS in which antibodies to antigens of the primary tumor cross-react with ocular antigens. This autoimmune response often leads to visual loss and other ocular dysfunctions.Endocrine Glands: Ductless glands that secrete HORMONES directly into the BLOOD CIRCULATION. These hormones influence the METABOLISM and other functions of cells in the body.Lambert-Eaton Myasthenic Syndrome: An autoimmune disease characterized by weakness and fatigability of proximal muscles, particularly of the pelvic girdle, lower extremities, trunk, and shoulder girdle. There is relative sparing of extraocular and bulbar muscles. CARCINOMA, SMALL CELL of the lung is a frequently associated condition, although other malignancies and autoimmune diseases may be associated. Muscular weakness results from impaired impulse transmission at the NEUROMUSCULAR JUNCTION. Presynaptic calcium channel dysfunction leads to a reduced amount of acetylcholine being released in response to stimulation of the nerve. (From Adams et al., Principles of Neurology, 6th ed, pp 1471)Endocrine System: The system of glands that release their secretions (hormones) directly into the circulatory system. In addition to the ENDOCRINE GLANDS, included are the CHROMAFFIN SYSTEM and the NEUROSECRETORY SYSTEMS.