Editing Lung cancer (section)

==Signs and symptoms==
Early lung cancer often has no symptoms. When symptoms do arise they are often [[Signs and symptoms#Nonspecific symptoms|nonspecific]] respiratory problems – [[cough]]ing, [[shortness of breath]], or [[chest pain]] – that can differ from person to person.{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}} Those who experience coughing tend to report either a new cough, or an increase in the frequency or strength of a pre-existing cough.{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}} Around one in four [[Hemoptysis|cough up blood]], ranging from small streaks in the [[sputum]] to large amounts.{{sfn|Nasim|Sabath|Eapen|2019|loc="Clinical Manifestations"}}{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}} Around half of those diagnosed with lung cancer experience shortness of breath, while 25–50% experience a dull, persistent chest pain that remains in the same location over time.{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}} In addition to respiratory symptoms, some experience [[systemic disease|systemic symptoms]] including [[anorexia (symptom)|loss of appetite]], [[weight loss]], general weakness, [[fever]], and [[night sweats]].{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}}{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}}

Some less common symptoms suggest tumors in particular locations. Tumors in the [[thorax]] can cause breathing problems by obstructing the [[trachea]] or disrupting the nerve to the [[thoracic diaphragm|diaphragm]]; [[dysphagia|difficulty swallowing]] by compressing the [[esophagus]]; [[hoarseness]] by disrupting the [[nerve]]s of the [[larynx]]; and [[Horner's syndrome]] by disrupting the [[sympathetic nervous system]].{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}}{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Horner's syndrome is also common in tumors at the [[Apex of lung|top of the lung]], known as [[Pancoast tumor]]s, which also cause [[shoulder pain]] that radiates down the little-finger side of the arm as well as destruction of the topmost [[rib]]s.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} [[Swollen]] [[lymph node]]s above the [[collarbone]] can indicate a tumor that has spread within the chest.{{sfn|Pastis|Gonzalez|Silvestri|2022|loc="Presentation/Initial Evaluation"}} Tumors obstructing bloodflow to the heart can cause [[superior vena cava syndrome]] (swelling of the upper body and shortness of breath), while tumors infiltrating the area around the heart can cause [[cardiac tamponade|fluid buildup around the heart]], [[arrhythmia]] (irregular heartbeat), and [[heart failure]].{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}}

About one in three people diagnosed with lung cancer have symptoms caused by [[metastases]] in sites other than the lungs.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Lung cancer can metastasize anywhere in the body, with different symptoms depending on the location. Brain metastases can cause [[headache]], [[nausea]], [[vomiting]], [[seizure]]s, and [[neurological deficit]]s. Bone metastases can cause pain, [[bone fracture]]s, and compression of the [[spinal cord]]. Metastasis into the [[bone marrow]] can [[cytopenia|deplete blood cells]] and cause [[leukoerythroblastosis]] (immature cells in the blood).{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Liver metastases can cause [[hepatomegaly|liver enlargement]], pain in the [[Quadrants and regions of abdomen|right upper quadrant of the abdomen]], fever, and weight loss.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}}

Lung tumors often cause the release of body-altering [[hormone]]s, which cause unusual symptoms, called [[paraneoplastic syndrome]]s.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Inappropriate hormone release can cause dramatic shifts in concentrations of blood [[Mineral (nutrient)|minerals]]. Most common is [[hypercalcemia]] (high blood calcium) caused by over-production of [[parathyroid hormone-related protein]] or [[parathyroid hormone]]. Hypercalcemia can manifest as nausea, vomiting, abdominal pain, constipation, [[polydipsia|increased thirst]], [[polyuria|frequent urination]], and altered mental status.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Those with lung cancer also commonly experience [[hypokalemia]] (low potassium) due to inappropriate secretion of [[adrenocorticotropic hormone]], as well as [[hyponatremia]] (low sodium) due to overproduction of [[antidiuretic hormone]] or [[atrial natriuretic peptide]].{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} About one of three people with lung cancer develop [[nail clubbing]], while up to one in ten experience [[hypertrophic pulmonary osteoarthropathy]] (nail clubbing, joint soreness, and skin thickening). A variety of [[autoimmune disease|autoimmune disorder]]s can arise as paraneoplastic syndromes in those with lung cancer, including [[Lambert–Eaton myasthenic syndrome]] (which causes muscle weakness), [[sensory neuropathies]], [[polymyositis|muscle inflammation]], [[encephalitis|brain swelling]], and autoimmune deterioration of [[cerebellum]], [[limbic system]], or [[brainstem]].{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Up to one in twelve people with lung cancer have paraneoplastic blood clotting, including [[migratory venous thrombophlebitis]], clots in the heart, and [[disseminated intravascular coagulation]] (clots throughout the body).{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}} Paraneoplastic syndromes involving the skin and kidneys are rare, each occurring in up to 1% of those with lung cancer.{{sfn|Horn|Iams|2022|loc="Clinical Manifestations"}}