TITLE:
Differentiation of Benign and Malignant Solitary Pulmonary Nodule: Literature Review
AUTHORS:
Suresh Tripathi, Xuqiu Zhen
KEYWORDS:
Solitary Pulmonary Nodule (SPN), Benign Pulmonary Nodule, Malignant Pulmonary Nodule, CT
JOURNAL NAME:
Advances in Lung Cancer,
Vol.4 No.2,
June
30,
2015
ABSTRACT: The solitary
pulmonary nodule (SPN) is frequently seen on chest radiographs and computed tomography
(CT), usually the identification is accidental. The overall prevalence of
malignancy is relatively low but identification of malignancy of nodule is of
prime importance. There are different characters of nodules indicating
malignancy, and also the exposure of person to risk factors increases the chances
of malignancy of nodule. Chances of malignancy rise with increasing size, the
irregular, lobulated border of the nodules is highly associated with higher
probability of malignancy and nodules with pure ground grass appearance have
higher probability of malignancy, irregularly marginated nodule displaying a
corona radiata sign indicating neoplastic infiltration with distortion of
neighbouring tissue is almost certainly a malignant nodule. Stippled,
punctuate, and eccentric calcifications are suggestive of malignancy. There
are 20% - 75% of chances of malignancy if nodule is appeared with ground-glass
opacity. Malignant nodules have higher growth rate as compared with benign
nodules, malignant nodules usually have doubling time (DT) of 30 - 400 days while
DT of more than 450 days is sign of benignity whereas doubling time less than
30 days is usually acute infectious process. The presence of fat within nodule
is sign of benignity. Increasing density of the nodule is suggestive of
malignancy and requires shorter follow up. Besides the nodule evaluation the
chances of malignancy can also be evaluated through the exposure of patient to
risk factors like age, current and past smoking status and history of extra
thoracic malignancy. The management depends upon various factors mainly three
strategies are applied for management including careful observation of nodule,
use of diagnostic techniques like CT FNA, PET, and broncoscopy and surgery.