Description

Overview

Our lungs are two spongy organs that are located in
the chest cavity and allow us to breathe.

Lung cancer is a type of cancer that originates from
lung tissues. Incidence of lung cancer is rising steadily worldwide and it is
the second most common cancer type. Moreover, it is leading cause of cancer
death in both men and women.

Risk Factors

Smoking is the most significant factor that causes the
lung cancer and it is responsible for the great majority of the lung cancer
cases.  Besides being active smoker, exposure to cigarette smoke in the
environment (passive smoking) is also an important risk factor for the lung
cancer. It is believed that cigarette smoke triggers the mechanism leading to
lung cancer by both the carcinogenic substances and chemicals it contains and
damaging the bronchial and alveolar walls. The probability of lung cancer due
to smoking is related with both the number of cigarettes smoked and how long
you have been an active smoker. It is also known that the probability of lung
cancer decreases over time if smoking is quitted that causes or contributes
onset of many extra conditions.

However, lung cancer may develop in individuals who
have never smoked or have not been exposed to environmental cigarette smoke.

Among the known risk factors of lung cancer are
exposure to asbestos and carcinogens as well as family history.

Types

Lung cancer has two major types; small cell lung
cancer and non-small cell lung cancer. Mesothelioma and carcinoid tumor are
rare cancers of lungs.

Symptoms

The early stage lung cancer usually does not cause
symptom or it is manifested by non-specific symptoms that can frequently be
seen in other diseases. These symptoms include:

• Chronic cough
• Blood in sputum (hemoptysis)
• Shortness of breath
• Wheezing
• Changes in your voice or hoarseness
• Unintended weight loss
• Bone and joint pains,
• Fluid accumulation in the chest

Prevention

As is the case for all other cancers, prevention of
lung cancer is also to eliminate or minimize manageable risks.

• Do not smoke or quit, if you smoke.
• Do not allow people to smoke in your environment
  or do not stay anywhere smoking is allowed.
• Toss all substances (radon, asbestos, etc) that
  are known to cause lung cancer out of your house and workplace.
• Have healthy eating habits. Prefer a diet rich in
  fruits and vegetables
• Exercise regularly, but take your general health
  condition into consideration.

Diagnosis

If the imaging studies (CT, MRI, PET) that are ordered
to investigate findings suspicious for cancer show a mass, provisional diagnosis
is made. The definitive diagnosis of the lung cancer requires taking a biopsy
specimen. Biopsy specimen is taken by bronchoscopy or in a surgery.

After the diagnosis of lung cancer is made, the next
step is to determine the stage. Your doctor will determine stage (I to IV) of
your cancer based on a set of very strict criteria.  You may think that
lung cancer is very broadly staged as local, limited or regional and distant.

Treatment

All data about patient and tumor are collected, the
most appropriate treatment approach is determined. Treatment of lung cancer
requires a rather though struggle. When possible treatment options are
reviewed, it is necessary to weigh possible benefits against possible adverse
effects and risks.

Although full recovery is the expected outcome for
tumors that are confined to lung(s), treatment outcomes and survival rates may
not be promising in cancers that have already spread to lymph nodes and/or
distant tissues and organs.

One of the most important factors that determine the
survival is the stage of the tumor at diagnosis. Unfortunately, most lung
cancer cases are diagnosed at the late stages (II or IV). Therefore, the lung
cancer is the leading cause of cancer death for both men and women worldwide.

Among the treatment options of the lung cancer are
chemotherapy, targeted treatment, radiotherapy and surgery. These treatments
can directly be used to treat the tumor or they are instituted to increase
quality of life and relieve symptoms in advanced stage cancers. Moreover, treatment
options can be used alone or in combination.

Chemotherapy

Chemotherapy uses drugs to treat the cancer. The
active substances of drugs kill the cancerous cells. Chemotherapeutic agents
can be given into a vein or be taken by mouth. In case of intravenous
administration, a thin tube, called catheter, is inserted into a great vein and
the chemotherapeutic agent is administered through this catheter throughout the
treatment period.

One or more than one chemotherapeutic agent can be
administered depending on the type of cancer and response to treatment. Active
chemotherapy maintained for a particular time is followed by an “off” period.
After the “off” period expires, the treatment resumes. Each of these sequential
active and “off” periods is called a cycle.

In the early stage lung cancers, chemotherapy may be
started before or after the surgery in order to both improve outcomes of
surgery and enhance the survival rates.

In the advanced stage cancers and small cell lung
cancers, the objective of the chemotherapy is to relieve symptoms, improve
quality of life and extend the life as much as possible.

Side effects of the chemotherapy are a function of the
chemotherapeutic agent and the dose. Most common side effects of
chemotherapeutics include; fatigue, nausea, vomiting, mouth sores, hair loss
and inflammation of the digestive system. Side effects caused by chemotherapy
will also be treated by your doctor. If these side effects are severe enough to
threaten your health, your doctor may advise to suspend the treatment or to
switch you to another chemotherapeutic agent.

Targeted Therapy

Targeted therapies are newer anti-cancer treatments
compared to chemotherapy. These medicines target specific abnormalities that
are present in cancerous cells. Before these medicines are started, cancer
cells are first analyzed in laboratories to determine whether they have
particular mutations or not.

Radiotherapy

Radiation therapy aims to kill cancer cells by using
high-powered energy beams.  

If the radiation source is out of the body and the
beams are directed to cancer, this treatment is called external radiotherapy.
 On the other hand, if the radioactive agent is placed at the locus of the
tumor through a needle or a catheter, method is called internal radiotherapy (brachytheraphy).

Although radiation therapy can be the first-line
treatment, it is usually used to kill cells that cannot be removed operatively.
In the first-line treatment, radiotherapy is mostly combined with chemotherapy
and this modality is also called chemoradiotherapy.  It plays an important
role in relieving or eliminating pain, shortness of breath and chronic cough in
advanced stage cancers.

If the lung tumor is very small in size, stereotactic
radiotherapy (radiosurgery) may be useful in killing cancer cells by focusing
radiation beams precisely on the tumor. In some cases, radiosurgery may remove
the requirement for traditional surgery. However, patient selection is a very
important issue for radiosurgery.

Radiotherapy has a very wide spectrum of side effects
depending on the body part irradiated. Sore throat, difficulty swallowing,
fatigue and loss of appetite are common side effects,you’re your doctor will
explain the risks that apply to you.

Surgery

Surgery is the first-line treatment for early stage cases
or tumors that are confined to the lung.

For lung resection, a segment, a lobe, two lobes or
the whole lung can be resected or surgically removed and a wedge-like part of
the lung is removed (wedge resection). Excluding wedge resection, all options are
commonly referred to as anatomic resection.

Thoracotomy implies the open surgery carried out for
lung resection. If technical means or patient and disease factors (location and
spread of the condition) allow, minimally invasive surgery, videothoracoscopic
surgery and robotic surgery are other options.

As thoracotomy offers the best exposure, a long
incision is made at level of the fifth rib and lungs are exposed.

All lung resections are major surgeries and therefore,
the patient should be very carefully prepped. Review of health history is
followed by a comprehensive physical examination. Blood tests are planned in
the light of signs and symptoms as well as physical examination data. Moreover,
advanced imaging studies, such as CT, MRI and PET/CT, are ordered to visualize
stage and spread of the condition and to plan the surgery.

Moreover, the patient is assessed by anesthesiologist
in order to manage anesthesia-related risks and extra examinations are ordered,
if required.

For lobectomy, the patient is transferred to the
operating suite and an intravenous access line is inserted. A sedative agent is
infused through this IV line to relax or calm down the patient. A tube is
inserted to the throat of the patient in order to maintain breathing during the
surgery. After anesthesia is administered, the patient is placed left lateral
decubitus position, if the right lung is resected, or the patient is placed
right lateral decubitus position, if the left lung is resected.

If open surgery (thoracotomy) will be carried out, an
incision, measuring approximately 25 cm in length, is made at level of the 5th
rib at the relevant side and lungs are exposed.

Small incisions are made for videothoracoscopic and
robotic surgeries and ports are inserted through the incisions. While a camera
is inserted through one of these ports, other ports serve insertion of surgical
tools into the chest cavity.

After lobectomy, bilobectomy, pneumonectomy (removal
of right or left lung completely) or wedge resection is carried out, two drains
are placed, one in the apex of the lung and the other at the base. These drains
function to drain fluid and blood and/or air that may accumulate in the body
after the surgery.

Finally, the large or small incisions are stitched and
closed with wound dressing.

Lobectomy – Bilobectomy: Lobectomy implies removal of a
whole lobe of the lung due to a lung pathology or primary or metastatic cancer.
As there are three lobes (upper, middle and lower lobes) are present in the
right lung, bilobectomy refers concomitant removal of the middle lobe or lower
or upper lobe. Thoracotomy is the open surgery method; however, if technical
means or patient and disease factors (location and spread of the condition)
allow, minimally invasive surgery, videothoracoscopic surgery and robotic
surgery are other options. Thoracic surgeon determines the best method
regarding the patient and the condition by reviewing all criteria.

Lobectomy is a major surgery and the artery that feed
the lobe and the vein that drains the dark blood in the lobe are tied and
cut/divided. Next, the bronchi of the lobe are similarly cut and the ends are
closed. The lobe is dissected off the adjacent tissues and the nearby lobe.

A cavity develops in the chest cavity after lobectomy
operations, but it is filled in as the rest lobe(s) will expand.

Segmentectomy: Lobes of lungs are divided into units,
called segment. A lung segment is a lung unit with own artery, vein and
bronchus. Ten segments are present in the right lung, while there are 8
segments in total in the left lung. Segmentectomy is the most minor one of the
anatomic resections. The basic principle is to tie and cut the artery, the vein
and the bronchus of the segment, occlude the end that is left inside the body
and to dissect off and remove the segment completely.

Pneumonectomy:

Pneumonectomy refers to total removal of right or left
lung. It is largely preferred for patients with lung cancer, who fulfill
necessary criteria. In case of pneumonectomy, patients should be far more
closely monitored and fluid intake and electrolytes should be very carefully
monitored and managed.

Wedge resection: It implies anatomic resection of
lungs. This method is preferred for lung biopsies or removal of lesions located
at the periphery of lungs. The periphery of lungs is removed in the form of
wedge or “V”.

Asking your questions about the treatment of lung cancer, your life
after treatment, rehabilitation, pain management, clinical studies and all the
questions in your mind about the lung cancer to your doctor will help you for
an informed participation to your treatment and alleviating your concerns.