What are the other Names for this Condition? (Also known as/Symptoms)

• Hamartoma of Lung

What is Pulmonary Hamartoma? (Definition/Background Information)

• Pulmonary Hamartoma (or Hamartoma of Lung) is a benign tumor of the lung, which can occur either in the lung tissue or within the bronchial airways
• These lung tumors are generally solitary and are observed in middle-aged and older adults. The exact cause of Pulmonary Hamartoma is unknown, and presently, no specific risk factors have been identified
• Most Pulmonary Hamartomas are asymptomatic, meaning that generally no signs and symptoms may be noted. Due to this reason, a majority of them are diagnosed incidentally, while a diagnostic work-up is being performed for other medical conditions
• The healthcare provider may undertake treatment (surgical removal of the tumor) in case it causes worrisome signs and symptoms, else a ‘wait and watch’ approach may be adopted
• The prognosis of Pulmonary Hamartoma is typically excellent since these are benign tumors and no malignant transformation is noted

Who gets Pulmonary Hamartoma? (Age and Sex Distribution)

• Pulmonary Hamartoma is usually observed in adults, in the 40-70 year age category
• The condition affects both males and females, but there is a predilection for males (male-female ratio is 5:2)
• This condition is observed worldwide and there is no racial or ethnic group predilection

What are the Risk Factors for Pulmonary Hamartoma? (Predisposing Factors)

• Currently, no risk factors have been identified for Pulmonary Hamartoma

It is important to note that having a risk factor does not mean that one will get the condition. A risk factor increases ones chances of getting a condition compared to an individual without the risk factors. Some risk factors are more important than others.

Also, not having a risk factor does not mean that an individual will not get the condition. It is always important to discuss the effect of risk factors with your healthcare provider.

What are the Causes of Pulmonary Hamartoma? (Etiology)

• The cause of development of Pulmonary Hamartoma is generally unknown
• It may be caused by certain genetic defects which are not yet well-characterised
• Research is currently being undertaken to identify the relevant causal factors

What are the Signs and Symptoms of Pulmonary Hamartoma?

Pulmonary Hamartomas can arise in the following lung parts:

• In the lung tissue or lung parenchyma (in about 95% of the cases), in which case the tumor is known as a Parenchymal Hamartoma
• Within the bronchial airways (remaining 5% of the cases), in which case the tumor is known as an Endobronchial Hamartoma

A majority of Pulmonary Hamartomas present no clinical indications and remain asymptomatic. The following features may be observed:

• It is a slow-growing tumor that is usually single; multiple tumors are observed very infrequently
• The tumor size is about (or less than) 4 cm, though some may be 10 cm or more. Some studies have revealed that the tumor size doubles every 400 days
• If the tumor occurs within the lung tissue (Parenchymal Hamartoma), no signs and symptoms are usually present
• Endobronchial Hamartoma also does not cause significant symptoms in a majority of individuals. In some cases, Endobronchial Hamartomas can cause coughing and blood in sputum

How is Pulmonary Hamartoma Diagnosed?

There are a variety of tests the healthcare provider may employ to detect and diagnose Pulmonary Hamartoma. These may include:

• Physical examination and complete medical history screening: During the physical exam, the healthcare provider may listen to the lung  with a stethoscope, to detect the presence of any abnormal lung sounds
• Imaging studies that may include a chest x-ray, MRI scan or CT scan of the lungs
• Arterial blood gases
• Lung function test
• Sputum cytology: This procedure involves the collection of mucus (sputum), coughed-up by a patient, which is then examined in a laboratory by a pathologist. This procedure may be performed, however no tumor cells may be noted

A tissue biopsy refers to a medical procedure that involves the removal of cells or tissues, which are then examined by a pathologist. This can help establish a definitive diagnosis. The different biopsy procedures may include: 

• Bronchoscopy: During bronchoscopy, a special medical instrument called a bronchoscope is inserted through the nose and into the lungs to collect small tissue samples. These samples are then examined by a pathologist, after the tissues are processed, in an anatomic pathology laboratory
• Thoracoscopy: During thoracoscopy, a surgical scalpel is used to make very tiny incisions into the chest wall. A medical instrument called a thoracoscope is then inserted into the chest, in order to examine and remove tissue from the chest wall, which are then examined further
• Thoracotomy: Thoracotomy is a surgical invasive procedure with special medical instruments to open-up the chest. This allows a physician to remove tissue from the chest wall or the surrounding lymph nodes of the lungs. A pathologist will then examine these samples under a microscope after processing the tissue in a laboratory
• Fine needle aspiration biopsy (FNAB): During fine needle aspiration biopsy, a device called a cannula is used to extract tissue or fluid from the lungs, or surrounding lymph nodes. These are then examined in an anatomic pathology laboratory, in order to determine any signs of abnormality
• Autofluorescence bronchoscopy: It is a bronchoscopic procedure in which a bronchoscope is inserted through the nose and into the lungs and measure light from abnormal precancerous tissue. Samples are collected for further examination by a pathologist

Note: A tissue biopsy is preferred to a fine needle aspiration biopsy, because of the uncommon nature of the tumor.

Many clinical conditions may have similar signs and symptoms. Your healthcare provider may perform additional tests to rule out other clinical conditions to arrive at a definitive diagnosis.

What are the possible Complications of Pulmonary Hamartoma?

There are no significant complications typically associated with Pulmonary Hamartoma. However, in some cases the following may be observed:

• Obstruction of the airways in case of a large-sized tumor
• Large tumors may also compress the heart and impede its functioning
• Severe chest pain
• Emotional stress in the individual, since the lung tumor may resemble lung cancer

How is Pulmonary Hamartoma Treated?

The treatment of Pulmonary Hamartoma may involve the following:

• In a majority of cases, removal of the tumor is not necessary, unless it causes bothersome signs and symptoms. In such cases, the healthcare provider may recommend a ‘wait and watch’ approach and regular checkups
• The treatment of choice is complete surgical excision, which can result in a cure
• Follow-up care with regular screening and check-ups are important and encouraged

How can Pulmonary Hamartoma be Prevented?

Currently, there are no known methods to prevent the development of Pulmonary Hamartoma.

What is the Prognosis of Pulmonary Hamartoma? (Outcomes/Resolutions)

• The prognosis for Pulmonary Hamartoma is generally excellent with appropriate treatment, since it is a benign tumor
• Studies have not indicated that this lung tumor type transforms into a malignancy
• Moreover, there is no risk of tumor recurrence on its complete removal

Additional and Relevant Useful Information for Pulmonary Hamartoma:

A Pulmonary Hamartoma is a benign tumor that is composed of different types of tissue such as cartilage, adipose tissue (fat), muscle tissue, and blood vessels.