This case demonstrates one of the "blind spots" in plain film radiography which is the hilum. Assessment of hila for abnormal contour, increase in the size is very important as changes may be subtle as in this case.

There are some areas that need special attention because pathology in these areas can easily be overlooked: apical zones, hilar zones, retrocardial zone and zone below the dome of the diaphragm.

These areas are also known as the hidden areas or blind spots in chest plain films.

Right lower lobe endobronchial biopsy: Non-small cell carcinoma favor Adenocarcinoma. Tumor cells are TTF+, CK5/6 -, and P63 -