Para Neoplastic Syndromes In Bronchogenic Carcinoma

Paraneoplasti c syndromes in bronchogenic carcinoma By Group 1 A students

Fifth year Alexandria faculty of medecine 2008-2009

Definition • Paraneoplastic syndromes • Clinical effects produced by a tumour that cannot be explained by the local or distant spread of the tumor or by hormones native to the tissue of origin of the tumor • They are triggered by the immune system's response to cancer cells, or by remote effects of tumor-derived factors.

Importance • Paraneoplastic syndromes are common in patients with lung cancer and may be the presenting finding or first sign of recurrence. • They may mimic metastatic disease and, unless detected, lead to inappropriate palliative rather than curative treatment. • They may represent significant clinical problems and may even be lethal.

Local Effects A single tumor mass may: *destroy a vital structure ; *obstruct or perforate a hollow organ (esophagus); *ulcerate a natural surface (mucosa); *undergo necrosis and predispose to infection; *cause bleeding (melena, hematuria), hemorrhage, thrombosis, infarction; *invade adjacent structures (e.g. the superior vena caval syndrome)

Superior Vena Cava Syndrome

:Systemic effects • Anemia may be caused by: *blood loss , or under production, *malnutrition, chronic infection, etc • Decreased resistance to infections * Weak immune responsiveness: * cytotoxic drugs, radiation therapy, * tumor products , tumor- cell invasion of bone marrow and lymphoid spaces. • Weight loss and cachexia • Fever :caused by pyrogenic cytokines produced by tumours (IL-1, TNF alpha…. etc)

Classification • Paraneoplastic syndromes can be divided into 4 main categories: Endocrine, neurological, mucocutaneous and hematological paraneoplastic syndromes, as well as others that may not fit into any of the above categories.

Endocrinal syndromes • Some tumors not originating in endocrine glands may produce ectopic hormones inappropriate for the tissue of origin causing multiple endocrinal syndromes such as: • Cushing syndrome • SIADH • Hypercalcemia • Carcinoid syndrome

Ectopic ACTH Syndrome Adrenocorticotrophin secretion

(ACTH)

stimulates

cortisol

mostly associated with cancer of the Lung (Small Cell Lung Cancer), Pancreas and Thymus. Excess ACTH Excess CORTISOL ==> Cushing’s (1) overproduction of cortisol (2) muscle wasting (3) hypokalaemia with metabolic alkalosis (4) “Moon” face and abdominal striae

SIADH

Neurologic syndromes • Lung cancer is one of the most common cancers associated with paraneoplastic neurological disorders. • 1% of cancer patients develop a neurologic PNS • Most are due to autoimmune phenomena • Ag expressed by tumour cells cause immune response and Ab cross-reacts with normal neuronal antigens

:Neurologic syndromes • These paraneoplastic disorders affect the central or peripheral nervous system and they are degenerative. • Symptoms of paraneoplastic neurological disorders may include ataxia , dizziness, nystagmus , difficulty swallowing, loss of muscle tone, loss of fine motor coordination, slurred speech, memory loss, vision problems, sleep disturbances, dementia, seizures, sensory loss in the limbs.

Neurological syndromes: • • • • • • • •

Lambert-Eaton myasthenic syndrome Paraneoplastic cerebellar degeneration Encephalomyelitis Limbic encephalitis Brainstem encephalitis Opsoclonus (involving eye movement) Encephalitis Polymyositis

Lambert-Eaton myasthenic (syndrome (LEMS • Lambert-Eaton myasthenic syndrome is a condition in which weakness results from an abnormality of acetylcholine release at the neuromuscular junction. It results from an autoimmune attack against voltage-gated calcium channels on the presynaptic motor nerve terminal • Cancer is present when the weakness begins or is later found in 40% of patients with LEMS. This is usually a small cell lung cancer (SCLC), although LEMS has also been associated with non-SCLC and other malignancies

Lambert-Eaton myasthenic syndrome • The typical patient with LEMS presents with slowly progressive proximal leg weakness. – Weak muscles may ache and are occasionally tender. – Oropharyngeal and ocular muscles may be mildly affected. – Respiratory muscles are not usually affected, but cases with severe respiratory compromise have been reported.

Lambert-Eaton myasthenic syndrome

Mucocutaneous: • • • • • • •

Acanthosis nigricans Dermatomyositis Leser-Trélat sign Necrolytic migratory erythema Sweet's syndrome Florid cutaneous papillomatosis Pyoderma gangrenosum

Hematological • • • • •

Granulocytosis Polycythemia Trousseau sign Nonbacterial thrombotic endocarditis Anemia

Others • Membranous glomerulonephritis • Tumor induced osteomalacia • Hypertrophic osteoarthropathy

Isolated clubbing also occurs in chronic obstructive lung disease and congenital cyanotic heart disease

Other syndromes Other syndromes        Hormone   Tumour type    Dermatomyositis                          None                      Carcinoma of lung, ovary, breast    Hypertrophic osteo­arthropathy   None                       Bronchogenic carcinoma  (Finger clubbing)    Myasthenia gravis                        None                      Thymoma    Autoimmune haemolytic anemia   None                      Chronic lymphocytic leukemia    Renal dysfunction                         None                      Multiple myeloma, colon cancer    Disseminated intravascular  coagulation (DIC)                        None                      Several Advanced cancers