Radiological imaging of
Dr/ ABD ALLAH NAZEER. MD.
Bronchogenic carcinoma, (or frequently known as lung
cancer) is the most common cause of cancer in men, and the 6th
most frequent cancer in women worldwide. It is the leading
cause of cancer mortality worldwide in both men and women
and accounts for approximately 20% of all cancer deaths.
The major risk factor is cigarette smoking which is implicated
in 90% of cases. Other risk factors include
radon, asbestos, uranium, arsenic, chromium, COPD and lung
Nearly 90% of lung cancer are related to smoking.
226,000 are newly diagnosed: 160,000 die of lung cancer per
The average 5 years is > 15% survival.
Squamous and adenocarcinoma have about the same 5-year
survival probability. It is worse for large cell carcinoma, and oat cell
carcinoma has almost no 5-year survival probability with a mean
lifespan of months from the time of diagnosis. Overall 8% of lung
cancer cases live past 5 years.
Squamous (epidermoid) carcinoma derived from reserve cells that
differentiate into squamous cells. Most commonly found centrally in
the lung, usually in the major lobar or first segmental bronchus.
Growth of the tumour occurs distally and proximally from site of
origin, destroying normal tissue and structures. Squamous
carcinomas tend to grow very large, and may kill by local growth.
These tumours often cavitate and resemble abscesses on
radiographic studies grossly. The tumour may be surgically resected
but cure rate depends on the clinical stage at the time of diagnosis.
Early diagnosis is possible by cytologic examination of a sputum
Most adenocarcinoma are insidious and asymptomatic for a long
time. Adenocarcinoma tend to occur more peripherally in the lung.
Adenocarcinoma is the one cell type of primary lung tumour that
occurs more often in nonsmokers. Treatment is surgical and involves
removal of the entire lobe with associated lymph nodes..
A subtype of adenocarcinoma. The tumour grows on the underlying
supportive structure of the lung parenchyma without causing much
damage to that structure. A rapid ‘pneumonic’ spread occurs to
other areas of the lung. Thus, on CXR it resembles a pneumonia-like
infiltrate rather than a mass.
Small cell carcinoma (‘oat cell’ carcinoma)
A highly malignant form of ‘neuroendocrine’ tumour. Derived from
reserve cells, differentiate towards neuroendocrine (Kulchitsky)
cells. Occur almost exclusively in smokers.
Often associated with paraneoplastic syndromes e.g. hormonal
effects - Ectopic ACTH production - Inappropriate ADH secretion.
Small cell carcinomas arise centrally and tends to spread diffusely
along and into the bronchial wall. Extensive necrosis within the tumour
is common due to its rapid growth outgrowing the blood supply.
Small cell carcinomas are not generally considered resectable
cancers since dissemination is likely to have occured by the time they
are discovered. They are responsive to chemotherapy. Radiotherapy
is also useful, but they are rarely curable.
Large Cell Carcinoma
Carcinomas which are so poorly differentiated that by routine light
microscopy they cannot be placed into either the epidermoid or
glandular groups. Ultrastructurally, however, these tumours frequently
demonstrate features of either epidermoid cells or glandular cells or
both. Arise centrally in lung. Highly aggressive tumours.
Spread of lung carcinoma
Lymphogenic to regional lymph nodes: -
hilar, mediastinal, supraclavicular.
Hematogenous: Adrenal glands, brain, bones, liver.
Bronchial obstruction ⇒ pneumonia, atelectasis, bronchiectasis distal
Infiltration of lung parenchyma, pleura, pericardium, chest
Infiltration of superior vena cava ⇒ SVC syndrome (swelling of
face, fullness of neck veins).
Apical tumours may infiltrate:
-Cervical sympathetic nerves ⇒ Horner’s syndrome (ptosis, miosis,
anhydrosis on same side of lesion).
-Brachial plexus ⇒ Pancoast syndrome (neurological manifestations
e.g. pain in upper extremity).
New T-staging according to the 7th edition of the TNM-staging of lung cancer
Stage I Non-Small Cell Lung Cancer.
Cancer is found only in the
lung, usually less than 3 cm and
not invading the bronchi.
Surgical removal recommended.
Radiation therapy and/or
chemotherapy may also be used.
Stage II Non-Small Cell Lung Cancer.
The cancer has spread to lymph
nodes in the lung, more than 3
cm, reaching pleura or
bronchi, but away from carina
more 2 cm.
Treatment is surgery to remove
the tumor and nearby lymph
radiation therapy sometimes
given after chemotherapy.
Stage III Non-Small Cell Lung Cancer.
The cancer has spread to the lymph nodes
located in the center of the chest, outside
the lung .
Stage IIIA cancer has spread to lymph
nodes in the chest, on the same side
where the cancer originated.
Stage IIIB cancer has spread to lymph
nodes on the opposite side of the
chest, under the collarbone, or the pleura
(lining of the chest cavity).
Surgery or radiation therapy with
chemotherapy recommended for stage
Chemotherapy and sometimes radiation
therapy recommended for stage IIIB.
Stage IV Non-Small Cell Lung Cancer.
The cancer has spread to
different lobes of the lung
or to other organs, such as
the brain, bones, and liver.
Stage IV non-small cell
lung cancer is treated with
Small Cell Lung Cancer–All Stages.
Patients with limited stage (confined to one area of the
chest) small cell lung cancer are treated with simultaneous
radiation therapy and chemotherapy.
Patients with extensive stage (not confined to one area of
the chest) small cell lung cancer are treated with
Because small cell lung cancer can spread to the
brain, preventative radiation therapy to the brain is
routinely recommended to all patients whose tumors
disappear following chemotherapy and radiation therapy.
Adenocarcinoma in a 41-year-old man with right shoulder pain for several months. (a)
Apical lordotic chest radiograph demonstrates a right apical mass with poorly marginated
borders. (b) Chest CT scan (lung window) shows a homogeneous peripheral right upper
lobe mass with irregular borders. There is tumor involvement of a posterior rib (arrow).
Chest wall invasion.
Can differentiate tumor tissue from chest wall muscles.
Cine MRI during breathing can assess the
tumor movement against the pleural surface.
In Pancoast’s tumors, MR can assess invasion of the
brachial plexus and subclavian vessels.
The accuracy of MRI versus CT in this domain in 94% for
MRI compared to 63% for CT.
Peripheral bronchogenic carcinoma with positive
axillary and mediastinal nodes by PET Scan.
Pulmonary lymphoma refers to lung parenchymal involvement
with lymphoma. It can be broadly divided as primary or
secondary. primary pulmonary lymphoma - (rare) usually non-
Hodgkin lymphoma which is limited to the lung with or without
mediastinal lymph node involvement and with no evidence of
extrathoracic dissemination for at least 3 months after the initial
diagnosis. low-grade B-cell lymphoma (MALToma) – commonest
80% of primary pulmonary lymphoma high grade B-cell
lymphoma - most commonly B-cell, occasionally anaplastic and
peripheral T-cell types primary pulmonary plasmacytoma
(rare)pulmonary intravascular lymphoma (rare) angiocentric
immunoproliferative lesion (lymphomatoid granulomatosis)
secondary pulmonary lymphoma - relatively common Hodgkin
disease, non-Hodgkin lymphoma
Two additional categories have also been described which include
lymphoma in patients with post-transplant lymphoproliferative
disorders (PTLD) AIDS-related pulmonary lymphoma (ARL - ARPL).
HRCT - chest
A number of features may be present on HRCT which include, a mass or
mass-like consolidation greater than 1 cm with or without cavitations or
bronchograms - most common finding according to one study masses of
pleural origin nodules less than 1 cm alveolar or interstitial infiltrates
peribronchial or perivascular thickening with or without atelectasis
pleural effusions, hilar or mediastinal lymphadenopathy
Pulmonary lymphoma in immune compromised patient.
Pulmonary metastases are common and the result of
metastatic spread to the lungs from a variety of tumours. Spread
can occur via blood, or lymphatics. The remainder of this article
concerns itself with hematogenous pulmonary metastases.
Lymphangitis carcinomatosis is discussed separately.
Pulmonary metastases from testicular cancer.