Brief Answer:
Surgery,prolonged immobility and cancer.

Detailed Answer:
Hello Madam!
I am Dr.Rovena and I read carefully your query.
I am sorry for all these health problems you are having.I understand you have gone through a lot.

Pulmonary thrombosis is when one or more pulmonary arteries in your lungs become blocked. In most cases, pulmonary embolism is caused by blood clots that travel to the lungs from the legs or rarely other parts of the body (deep vein thrombosis, or DVT).

Anyone can develop blood clots and subsequent pulmonary thrombosis but certain factors can increase your risk.
These factors include:
1) certain medical problems put you at risk that include:
-Cancer because they can increase levels of substances that help blood clot, and chemotherapy further increases the risk.
-Heart diseases.

2)Prolonged immobility because blood clots are more likely to form in your legs during periods of inactivity, such as bed rest. Being confined to bed for an extended period after surgery make you far more vulnerable to blood clots. When the lower extremities are horizontal for long periods of time, the flow of venous blood slows and blood pools in the legs.

3)Surgery is one of the leading causes of problem blood clots.Being immobile during any type of surgery can lead to the formation of clots. The risk increases with the length of time you are under general anesthesia.

Since you had 3 major risk factors such as cancer,surgery and immobility after surgery you were very susceptible to blood clot formation and then traveling to the lungs and causing pulmonary thrombosis.

In this cases when these risk factors are known, the patients that are going to have a surgery will receive medication before and after surgery to prevent clot formation and continued after surgery.It seems that in your case the treatment wasn't able to prevent clot formation.

Hope my answer has helped.
If you have any further question please feel free to ask me,I will be happy to help.
Wish you a good health.

Dr.Rovena

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