Sandbox:Mazia

# Overview
History
Patients with Pancoast syndrome may present with referred pain over the scapula to the shoulder as the result of damage to the afferent pain fibers of the sympathetic trunk. The symptoms are typical of the location of the tumor in the superior sulcus or thoracic inlet adjacent to the eighth cervical nerve roots, the first and second thoracic trunk distribution, the sympathetic chain, and the stellate ganglion.
Initially, localized pain occurs in the shoulder and vertebral border of the scapula. Pain may later extend along an ulnar nerve distribution of the arm to the elbow and, ultimately, to the ulnar surface of the forearm and to the small and ring fingers of the hand (C8). If the tumor extends to the sympathetic chain and stellate ganglion, Horner syndrome and anhidrosis develop on the ipsilateral side of the face and upper extremity.
The pain is frequently relentless and unremitting, and adequate relief often requires administration of narcotics. The patient usually supports the elbow of the affected arm in the hand of the opposite upper extremity to ease the tension on the shoulder and upper arm.
The hand muscles may become weak and atrophic, and the triceps reflex may be absent. The first or second rib or vertebrae may be involved by tumor extension and intensify the severity of pain. The spinal canal and spinal cord may be invaded or compressed, with subsequent symptoms of spinal cord tumor or cervical disk disease.
Many patients are initially treated for presumed local musculoskeletal conditions such as bursitis and vertebral osteoarthritis with radicular pain. Symptoms may persist for many months before evaluation for progression reveals the cause. In a 1994 series by Maggi et al, symptoms lasted 2-36 months, with a mean of 9.7 months.  In 1997, Muscolino described plexopathy or radicular symptoms in 53% of 15 patients. 

# Historical Perspective
-  was first discovered by , a , in  during/following .
- In ,  mutations were first identified in the pathogenesis of .
- In , the first  was developed by  to treat/diagnose .

# Classification
-  may be classified according to  into  subtypes/groups:
- Other variants of  include , , and .

# Pathophysiology
- The pathogenesis of  is characterized by , , and .
- The  gene/Mutation in  has been associated with the development of , involving the  pathway.
- On gross pathology, , , and  are characteristic findings of .
- On microscopic histopathological analysis, , , and  are characteristic findings of .

# Causes
-  may be caused by either , , or .
-  is caused by a mutation in the , , or  gene.
- There are no established causes for .

# Differentiating  from other Diseases
-  must be differentiated from other diseases that cause , , and , such as:

# Epidemiology and Demographics
- The prevalence of  is approximately  per 100,000 individuals worldwide.
- In , the incidence of  was estimated to be  cases per 100,000 individuals in .

## Age
- Patients of all age groups may develop .
-  is more commonly observed among patients aged  years old.
-  is more commonly observed among .

## Gender
-  affects men and women equally.
-  are more commonly affected with  than .
- The  to  ratio is approximately  to 1.

## Race
- There is no racial predilection for .
-  usually affects individuals of the  race.
-  individuals are less likely to develop .

# Risk Factors
- Common risk factors in the development of  are , , , and .

# Natural History, Complications and Prognosis
- The majority of patients with  remain asymptomatic for .
- Early clinical features include , , and .
- If left untreated,  of patients with  may progress to develop , , and .
- Common complications of  include , , and .
- Prognosis is generally , and the  of patients with  is approximately .

# Diagnosis

## Diagnostic Criteria
- The diagnosis of  is made when at least  of the following  diagnostic criteria are met:

## Symptoms
-  is usually asymptomatic.
- Symptoms of  may include the following:

## Physical Examination
- Patients with  usually appear .
- Physical examination may be remarkable for:

## Laboratory Findings
- There are no specific laboratory findings associated with .
- A    is diagnostic of .
- An  concentration of   is diagnostic of .
- Other laboratory findings consistent with the diagnosis of  include , , and .

## Imaging Findings
- There are no  findings associated with .
-  is the imaging modality of choice for .
- On ,  is characterized by , , and .
-  may demonstrate , , and .

## Other Diagnostic Studies
-  may also be diagnosed using .
- Findings on  include , , and .

# Treatment

## Medical Therapy
- There is no treatment for ; the mainstay of therapy is supportive care.
- The mainstay of therapy for  is  and .
-  acts by .
- Response to  can be monitored with  every .

## Surgery
- Surgery is the mainstay of therapy for .
-  in conjunction with  is the most common approach to the treatment of .
-  can only be performed for patients with  .

## Prevention
- There are no primary preventive measures available for .
- Effective measures for the primary prevention of  include , , and .
- Once diagnosed and successfully treated, patients with  are followed-up every . Follow-up testing includes , , and .