Hello and Welcome to healthcare magic forum!
The X-ray is the first test your doctor performs to see if your lungs have any spots which are caused by nodules in the lung,
the "spot on the lung" or nodule is caused by the following reasons :
1. Tuberculosis
2. Pnuemonia
3. Histoplasmosis
As your friend stays in an extreme
cold weather conditions in Arizona it might be a possible
lung infection. So, check to see if she has any
fever breathlessness and blood streaks in the phlegm.
Some tests which might confirm diagnosis and rule out if the nodule is benign or cancerous,are:
1. Tuberculin skin test
2. CT scan
3. MRI
4. Biopsy
5. Blood tests though are not completely diagnostic are mandatory , like Total count,
WBC, Platelets, Alakaline phosphatase, serum calcium,
Immunoglobulin G and M
I would suggest you to take her to a pulmonologist who would evaluate the results of these tests and give the proper treatment.
Wishing you friend Complete recovery!