From Michael Finnegan:

“Before the operation, a few cancer cells may have escaped into nearby lymph nodes, the bloodstream or other tissues. They may be too small to detect on scans. Those cells can survive the operation and later form new tumours.

“If the tumour was not removed completely, or cancer cells remain in nearby tissue, the disease may persist or subsequently recur at the original site.

Removing a cancerous lung nodule cannot guarantee that every cancer cell has been eliminated. Cancer can recur even after surgery.

“Apart from cancer there is also the possibility of infection after lung surgery
– Pneumonia: an infection in the remaining lung tissue.
– Surgical wound infection: infection around the incision in the chest.
– Infection in the chest cavity: infection in the space surrounding the lung, sometimes involving fluid or pus.
– Bloodstream infection or sepsis: a more serious complication in which infection triggers a dangerous response throughout the body.

“Chest drains are routinely used after many types of lung surgery, including operations to remove a cancerous nodule. Their purpose is to drain air and fluid from around the lung so that it can expand properly again.

“A tube passes through the chest wall into the space between the lung and the ribs. It drains air, blood and other fluid into a collection bottle. This helps the lung re-expand. It does not normally clean the inside of the lung or suck mucus out of the airways.

“Once the drains and other temporary equipment have been removed, the patient may still experience pain, fatigue, breathlessness on exertion and reduced stamina for several weeks. Recovery depends on whether the surgeon removed only a small wedge of lung tissue or a larger portion, such as an entire lobe.”