Download Benign Lung Tumors

Lung Neoplasm
Benign Lung Tumors:
Benign tumors of the lung are uncommon and account for fewer than 15% of solitary lesions seen
on chest radiographs
Classification of benign tumors of the lung:
Benign tumors of the lung can arise from all of the various cell types that are present in the lung
1. Epithelial tumors: e.g.; papillomas, and polyps
2. Mesodermal tumors: e.g.; Angioma, lymphangioma, fibroma, chondroma, lipoma,
leimyoma.
3. Neurogenic tumors: e.g.; neurofibroma
4. Developmental tumors or tumors of unknown origin e.g.: Hamartoma, Teratoma and
chemodectoma
5. Inflammatory and other pseudotumors e.g.; amyloidosis, tuberculoma …etc
Clinical presentation:


Asymptomatic and detected only on CXR (A peripheral tumor usually causes no symptoms
until it is large; a central tumor may present with symptoms while small).
Symptomatic in only 40%

Cough, chest pain, bronchial obstruction (causing wheezing and history of recurrent
pneumonia, bronchiectasis or lung abscess)

Hemoptysis is rare and associated with endobronchial and/or endotracheal lesions
Investigations:
1. CXR: usually appear as well circumscribed homogenous or non homogenous opacity of
various size. Points that may suggest a benign rather than malignant lesion on CXR are:
a. It has not increased in size on chest radiographs for more than 2 years
b. Presence of calcification
2. CT scan
3. PET scan (Positron Emission Tomography)
4. Biopsy: needle, incisional or excisional biopsy determines the definite diagnosis
Treatment:
For most benign lesions, treatment is conservative pulmonary resection which establishes the
diagnosis. Some may be treated by endobroncheal removal. Most times benign nodules are
excised because of the inability to differentiate them from a malignant process.
Lung Cancer:
Lung cancer is one of the most common cancers throughout the world. And it is the most common
cause of death from malignancy in both men and women. From the time of diagnosis, 80% of
patients are dead within 1 year and only 5% survive for 5 years.
Risk factors for pulmonary carcinoma:
Cigarette smoking is the major risk factor for developing bronchial carcinoma and accounts for 85–
95% of all cases. To a lesser extent, atmospheric pollution and certain occupations (radioactive ore
(‫ )معدن خام‬and chromium mining) contribute. Chronic obstructive pulmonary disease (COPD) has
also been demonstrated to be a predisposing factor in the development of carcinoma of the lung.
Pathological classification:
For practical purposes, lung cancers are divided into small cell and non-small cell lung cancer (SCLC
& NSCLC).
Small cell lung cancers represent about 20% of all lung cancer. They tend to metastasize early to
lymph nodes and by blood-borne spread. The median survival is measured in months. The tumors
are very responsive to chemotherapy such that median survival may be doubled (but is still short),
but they are rarely, if ever, cured. Surgery has little place. SCLS is subdivided into:
 Oat cell ca
 Intermediate
 Combined oat cell ca
The remaining cell types, together are considered as non–small cell lung cancer (NSCLC), and
represent 75% to 80% of all lung carcinomas and are discussed collectively, because therapeutic
approaches to patients with any of these cell types are identical. The three major histological
types of NSCLC are
 Adenocarcinoma,
 Squamous cell carcinoma,
 Large cell carcinoma.
 Other less common histological types
Adenocarcinoma is now the most common of the NSCLC types. It constitutes approximately 50%
of patients with lung cancer. Adenocarcinomas are often peripheral lesions and tend to invade
the pleura.
Squamous cell carcinoma represents approximately 30% of all lung cancers. Squamous
carcinomas originate centrally, grow toward the mainstem bronchus, and invade bronchial
cartilage, pulmonary parenchyma, and mediastinal lymph nodes.
Clinical manifestations
Only 6% of patients are asymptomatic at the time of diagnosis. Clinical features of lung carcinoma
depend on:
 The site of the lesion;
 The invasion of neighboring structures;
 The extent of metastases.
So symptoms can be generally divided into the following:
I- Pulmonary symptoms:
1) Persistent cough
2) Dyspnea which may be due to loss of functional lung tissue, development of large
pleural effusion, paralysis of diaphragm or major bronchial obstruction.
3) Hemoptysis: in less than 50% usually as blood streaks with the sputum but massive
hemoptysis is unusual.
4) Stridor and wheeze
5) Chest pain which may be dull and in the form of heaviness due to the weight of the
tumor or sharp and severe due to chest wall and intercostal nerve involvement
II- Extrapulmonary intrathoracic symptoms
Caused by invasion, irritation or compression of the adjacent structures e.g.;
1) Nerves:
a. Recurrent laryngeal nerve (usually left) → vocal cord palsy and hoarseness of
voice.
b. Phrinic nerve → diaphragmatic eventration (elevation of the hemidiaphragm)
c. C8 & T1 (of the brachial plexus) → due to superior sulcus tumor or pancoast
tumor
d. Sympathetic nerve → Horner's syndrome
2) SVC → SVC syndrome.
3) Pleural involvement → pleural effusion
4) Pericardium and heart → tamponade, heart failure and arrhythmias
II- Paraneoplastic syndromes:
These are symptoms, or findings that are related to the primary tumor or its metastases by
hormonal intermediates. It includes:
1) Endocrine e.g.: Cushing's syndrome (due to ectopic ACTH production) hyponatremia and
volume overload (due to ADH), Hypercalcemia (due PTH)
2) Neurological e.g.: Polyneuropathy, Myelopathy
3) Others e.g.: Finger clubbing due to hypertrophic pulmonary osteoarthropathy,
Myasthenia gravis …etc.
III- Extrathoracic metastatic manifestations: Spread to liver, brain, bone and skin. Most frequently
to brain and bone.
Investigations:
Investigations are undertaken to confirm the diagnosis, determine the tumors histological type and
assess its clinical stage, in addition to assessing the patient's ability to tolerate surgery with major
pulmonary resection.
1) CXR: will detect most lung cancers which appear as a central or peripheral opacity
(homogenous or non homogenous) usually with poor defined margins and sometimes sun
ray appearance. Other features include, pleural effusion, atelectasis, and elevated
diaphragm.
2) CT scan: effective in evaluating the primary lesion and assessing regional and mediastinal
lymph node involvement.
3) MRI
4) PET scan (Positron emission tomography) is a noninvasive imaging method that has
demonstrated increased glucose metabolism in malignant cells.
5) Sputum cytology: Simple, quick, non-invasive and can be repeated and most likely gives
positive results.
6) Bronchoscopy: Flexible fiberoptic bronchoscopy is important for both visualization of the
tumor, and obtaining tissue for histological diagnosis by bronchial biopsy, brushings, or
washings.
7) Transthoracic needle aspiration for cytology: either blindly or using fluoroscopic,
ultrasonographic, or CT guidance
8) Mediastinoscopy: for assessing mediastinal lymph node involvement
9) VATS or thoracotomy if above methods for obtaining tissue diagnosis fail.
Staging of lung cancer:
Staging of NSCLC: According to the tumor–node–metastasis (TNM) staging system which gives
best prognostic information.
Lung cancer is considered inoperable according to TNM staging when:
1- Tumor with extension to nearby structures or within 2 cm from the carina (T3)
2- Metastasis to mediastinal or subcarinal LN (N2)
3- Presence of distant blood born metastasis (M1)
4- Stage III or more of TNM staging system
Primary tumour (T)
TX
Tumour proven by the presence of malignant cells and bronchial secretions, but not visualised by
radiography or bronchoscopy
T0
No evidence of primary tumour
TIS
Carcinoma in situ
T1
A tumour that is 3 cm or less in greatest dimension, surrounded by lung or visceral pleura and
without evidence of invasion proximal to a lobar bronchus at bronchoscopy
T2
A tumour of more than 3 cm in greatest dimension or a tumour of any size that either invades the
visceral pleura or has associated atelectasis or obstructive pneumonitis. at bronchoscopy, the
proximal extent of demonstrable tumour must be within a lobar bronchus or at least 2 cm distal to
the carina
T3
A tumour of any size, with direct extension into the chest wall, diaphragm, mediastinal pleura or
pericardium, without involving the heart, great vessels, trachea, oesophagus or vertebral body, or a
tumour in the main bronchus within 2 cm of the carina without involving the carina
T4
A tumour of any size, with invasion of the mediastinum or involving the heart, great vessels,
trachea, oesophagus, vertebral body or carina, or the presence of malignant pleural effusion
Nodal involvement (N)
N0
No demonstrable metastasis or regional lymph node
N1
Metastasis to lymph nodes in the peribronchial or the ipsilateral hilar region, or both
N2
Metastasis to the ipsilateral, mediastinal and subcarinal lymph nodes
N3
Metastasis to the contralateral mediastinal lymph nodes, contralateral hilar lymph nodes, ipsilateral
or contralateral scalene or supraclavicular lymph nodes
Distant metastasis (M)
M0
No known distant metastasis
M1
Distant metastasis present
Staging of SCLC: The TNM staging system has not proved to be prognostically useful for SCLC.
Currently, most thoracic oncologists utilize a staging system that divides patients with SCLC into
two major groups:
 Limited disease: when the disease is confined to the hemithorax and no detectable distant
metastases.
 Extensive disease is characterized by involvement of the contralateral thorax or the
presence of distant metastases
Treatment of NSCLC:
Treatment for lung cancer depends on the cancer's specific cell type, how far it has spread, and
the patient's performance status. Common treatments include palliative care, surgery,
chemotherapy, and radiation therapy
I- Surgical treatment:
The principle of surgery is to remove all cancer (the primary and the regional lymph nodes) but to
conserve as much lung as possible. Anatomical resection is generally preferred for this purpose.
Complications of pulmonary resection:
1) Bleeding: > 200 ml/hour for 3 consequent hours
Management:
a. Assess vital signs, tube patency with close observation
b. Replace volume by i.v. fluid and blood
c. Assess coagulation profile (history and blood tests) and treat accordingly
d. If bleeding continues despite that prepare for re-exploration.
2) Respiratory infection (atelectasis/pneumonia): due to poor postoperative physiotherapy and
retained secretions, causing fever, cough and sputum with consolidation on CXR.
Management:
a. Encourage physiotherapy
b. Analgesics
c. Broncho-dilators and pulmonary expectorants
d. Antibiotics
3) Respiratory failure: due to postoperative pulmonary edema, atelectasis, or ARDS
Management:
a. Maintain the patient on mechanical ventilation
b. Treatment of the cause
4) Persistent air leak: prolonged or persistent air bubbling in the chest tube for more than 7 days
postoperatively (normally air leak stops within 2-3 days postoperatively)
Management:
a. Assess tube consistency and patency
b. Place chest tube on suction
c. Add another chest tube
5) Bronchopleural fistula: persistent connection between the bronchus and the pleural space
Management:
a. Prolong chest tube aspiration
b. Small fistula may be closed bronchoscopically by fibrin glue
c. Re-exploration and stump closure with re-enforcement with muscle or pleural flap
6) Broncho-vascular fistula: rare complication presented with a mild herald bleeding followed by
massive hemoptysis
Management:
a. Volume replacement
b. Re-exploration with stump and artery re-enforcement
7) Post operative pain: It is important to deal with post-thoracotomy pain effectively so that a
normal breathing pattern and gas exchange are achieved in the early postoperative period.
Three strategies are routinely used in combination:
a. Patient-controlled analgesia (PCA) with intravenous boluses of opiates;
b. Paravertebral, extrapleural catheter-delivered local anaesthetic;
c. Epidural analgesia
d. Background oral analgesia with paracetamol.
8) Post pneumonectomy syndrome: Torsion or compression of the trachea, bronchus or
pulmonary vasculature due to mediastinal shift leading to dyspnea. It is a rare complication
occurring months to years post pneumonectomy.
Management: silicone implants (similar to breast implants) are placed into the chest to fill the
space.
II- Chemotherapy:
Approximately 60% of patients with NSCLC have distant metastases at the time of initial diagnosis.
Chemotherapy may be used as an adjuvant with surgery or radiotherapy or alone. A variety of
therapeutic agents have been used however chemotherapy when used alone induces tumor
regression in only 5% of patients.
III- Radiotherapy:
Radiotherapy can be used as adjuvant to surgery or solitary for cure. Its response is greater than
that of chemotherapy, but still less than that of surgery, accompanied by much more
complication, lower patient tolerance and require much longer time.
IV-Palliative care:
Palliative care is an area of healthcare that focuses on relieving and preventing the suffering of
patients. Palliative medicine is appropriate for patients in all disease stages, including those
undergoing curable treatment as well as patients with incurable disease nearing the end of life.
V- Multimodality therapy:
Various combinations of chemotherapy and radiotherapy after or before surgery with the aim to
increase resectability of the tumor and decrease recurrence.
Treatment of SCLC:
It progresses relentlessly and behaves as a systemic disease. Locoregional therapy directed toward
the primary tumor is ineffective in prolonging survival because the majority of patients present
with distant metastases.
Multimodal therapy including effective chemotherapy is therefore required for both locoregional
control and systemic treatment of SCLC.