Paraneoplastic syndromes, with lung cancer

Paraneoplastic syndromes are clinical syndromes owing to nonmetastatic systemic effects of cancer. Tumors make and secrete biologically active products that can stimulate or inhibit hormone production, autoimmunity, immune complex production, or immune suppression. Lung cancer, particularly small cell lung cancer, is associated with a high rate of paraneoplastic... 

Becldes MA, Spiro SG, Colice GL, et al. Initial evaluation of the patient with lung cancer Symptoms, signs, laboratory tests, and paraneoplastic syndromes. Chest 2003 123(1 suppl) 97S-104S. 

Paraneoplastic syndromes commonly associated with lung cancers include cachexia, hypercalcemia, syndrome of inappropriate antidiuretic hormone secretion, and Cushing s syndrome. 

Cancer patients often develop symptoms from organs remote from the primary tumor. The symptoms are usually caused by metastasis or toxic effects of therapy and less often by such secondary factors as nutritional deficiency, metabolic disturbances, opportunistic infections, and effects of critical illness. Other systemic diseases such as diabetes or amyloid may become manifest or aggravated during the course of the cancer disease and cause symptoms from remote organs. Paraneoplastic neurological syndromes (PNS) are a rare cause of remote symptoms [1]. The PNS affect less than 1% of all cancer patients [2], Even in small cell lung cancer (SCLC), the tumor type most commonly associated with PNS, these disorders occur in less than 5% of the patients [3, 4],... 

Paraneoplastic autonomic neuropathy is primarily seen with SCLC [103]. Lymphoma, non-small cell lung cancer, and ovarian cancer are also associated with autonomic disturbances [104]. Autonomic dysfunction affects 23-30% of Hu antibody positive patients [36, 98] and is the predominant symptom at presentation in up to 9% of the patients [90]. The onset of symptoms is usually subacute. A prominent clinical manifestation in patients with paraneoplastic autonomic neuropathy is gastrointestinal dysmotility and intestinal pseudo-obstruction, which can occur as part of the PEM/SN syndrome or as the sole symptom of Hu antibody related PNS. Ortostatic hypotension and erectile dysfunction are other common features [37, 105, 106], Autonomic neuropathy is also commonly associated with the CRMP-5 antibody and have been detected in more than 30% of CRMP-5 antibody positive patients [30], Inflammation in autonomic ganglia and infiltration of B and T cells have been demonstrated at autopsy [107], and Hu antibodies have been shown to induce neuronal apoptosis in cultured myenteric neurons [105],... 

Neuromyotonia, or Isaacs syndrome, can occur as a paraneoplastic manifestation [138]. In a study of 60 patients with neuromyotonia, 8 individuals developed lung cancer or malignant lymphoma [139]. Importantly, and in contrast to most other PNS, the tumors presented after the symptoms of nerve hyperexitability, in some cases up to 4 years later. This long latency has also been reported in LEMS with SCLC [140]. 

Elrington GM, Murray NM, Spiro SG, Newsom-Davis J. Neurological paraneoplastic syndromes in patients with small cell lung cancer. A prospective survey of 150 patients. J Neurol Neurosurg Psychiatry 1991 54(9) 764-767. 

Vascular and collagen disorders (systemic lupus erythematosus, scleroderma, rheumatoid arthritis, and others) Paraneoplastic syndrome (associated with lung, prostate, breast cancer, or hematological diseases)... 

Patients with lung cancer frequently have numerous concurrent medical problems. Such problems may be related to invasion of the primary tumor and its metastases, paraneoplastic syndromes (see clinical presentation, above), chemotherapy and radiotherapy toxicity, or concomitant disease states (e.g., cardiac disease, renal dysfunction, chronic obstructive pulmonary disease, asthma, or diabetes). Depression is also common and sometimes persistent in patients with SCLC and NSCLC and should be treated. Identification, diagnosis, and treatment of the patient as a whole may improve the patient s overall quality of life and tolerance to cancer treatments. 

Lambert-Eaton myasthenic syndrome (LEMS). Paraneoplastic neurological disorder associated with small-cell lung cancer and caused by autoantibodies against voltage-gated calcium channels. 

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