Diameter, thickness and discordance degree of solitary pulmonary cavitary lesion to differentiate benign from malignant lesions : a mutlislice ct study

الملخص EN

Cavities are frequent image findings in a variety of pulmonary diseases including both lung cancer and pulmonary tuberculosis, Computed Tomography (CT) is accepted as the modality of choice for detection of possible cavitating pulmonary nodules.

The aim of this study is to assess the role of diameter, thickness and discordance degree of solitary pulmonary cavitary lesion to differentiate benign from malignant lesions in multislice CT.

This cross sectional study was done in the Computed Tomography Unit of Al-Imamain Al- Kadhimain Medical City, Baghdad, Iraq and Al-Sader Teaching Hospital, Basrah, Iraq between October 2016 and June 2017.

All patients are with solitary pulmonary cavitary lesions detected by chest x-ray referred for different reasons.

Exclusion criteria included: multiple cavitary lung lesions, patients with known lung carcinoma or pulmonary tuberculosis on treatment, and patients receiving chest radiotherapy for different reasons.

CT examination of the chest was performed by multi-detector CT (Somatom definition edge, SIEMENS (256 slices)) with 2 sets of CT examination one before and another after giving IV nonionic iodinated contrast medium (Ultravist 370 mg /ml), 1.5 ml/kg Body weight.

The final diagnosis was obtained depending on the sputum culture for AFB, bronchoscopy and biopsy, bronchoscopy and brush cytology and true cut biopsy.

Eighty percent of the patients were diagnosed as having benign lesions and 20 % were diagnosed as having malignant lesions, the most frequent diagnosis was TB (60 %), followed by squamous cell carcinoma (14 %), lung abscess (10 %), hydatid cyst (10 %), adenocarcinoma (4 %), and metastasis (2 %).

The discordance of CT scan (FDCW3) show highly significant association with malignant solitary cavitary lesions, while CT concordance (FCCW1 and FCCW2) were significantly associated with benign solitary cavitary lesions (p < 0.001).

A highly significant association was observed between increased mean thickness and increased mean diameter of lesion and malignant solitary cavitary lesion (p < 0.001).

In conclusion, multi-slice computerized tomography is an appropriate diagnostic modality for differentiation between benign and malignant solitary pulmonary cavitary lesions.

Increased diameter and thickness of pulmonary cavities and increased discordance degree are more likely to predict malignancy.