After a corona infection, a wide variety of symptoms can still appear for weeks and months. Some of these are similar to the signs of lung cancer, some go in a different direction. Where there are overlaps, which differences are typical and when you definitely need to see a doctor.

First Corona, then negative tests, so the virus has disappeared from the upper respiratory tract, but healthy feels different. Up to 30 percent of those who have recovered have ongoing health problems after infection, experts say.

There is no typical symptom of long-Covid, nor is there a biomarker, as far as is known. The signs of Long-Covid are very different, over 200 different symptoms have been registered so far.

The symptoms can be mild or severe, individually, but also several in combination. The most common symptoms of Long-Covid include:

There are indications that there are two different forms of long-Covid: in one, exhaustion, i.e. fatigue, predominates, in the other physical complaints.

Anyone who has persistent symptoms after a corona infection will probably first think of Long-Covid – and in most cases they are certainly right. But this may overlook the fact that it may also be lung cancer, one of the deadliest and most common cancers.

Lung cancer is the second most common cancer in men in Germany after prostate cancer. In women, the third most common after breast and colon cancer, as reported by the German Cancer Society. Almost 55,000 new cases of lung cancer are diagnosed in Germany every year. It is therefore quite possible that lung cancer symptoms occur for the first time by chance after a corona infection.

There are no typical signs in the early stages, but gradually these symptoms can appear:

Each of these lung cancer signs can also come from another illness, such as bronchitis, bacterial infections and pneumonia, as well as others – such as Long-Covid. The similar symptoms that can occur in both lung cancer and long-Covid are:

The explanation for this overlapping of symptoms: Both long-Covid and lung cancer can restrict lung function, coughing and breathing difficulties occur. The oxygen supply is no longer optimal, which can also manifest itself in general poor performance. In addition, the immune system can still be highly activated after the corona infection, so it works constantly under pressure, which also drains your strength. The same applies to the fight against cancer, which also leads to rapid exhaustion. Coughing, shortness of breath and general exhaustion can therefore indicate both long-Covid and lung cancer.

As great as the similarity of these three symptoms is at first glance, the differences in the many other signs of lung cancer and long-Covid are also clear: the heart problems, memory disorders, problems with smell and taste typical after Corona are not part of the range of possible signs of lung cancer.

However, there is also a difference in the similar symptoms, which only becomes apparent over time: if it is long-Covid, there is a tendency towards improvement over the weeks. Cough, shortness of breath and exhaustion slowly disappear. Experts assume that after eight weeks only five of the original 100 long-Covid patients still have symptoms. Because the vascular inflammation, which is probably the cause of many long-Covid symptoms, is gradually disappearing.

However, if the cause of the above symptoms is lung cancer, they worsen, and more appear as the cancer progresses.

Waiting to see whether symptoms such as coughing, shortness of breath and exhaustion will improve over time, and whether it is “only” long-Covid and not lung cancer, is not an option. The chances of curing cancer are better the earlier the diagnosis is made and the earlier the corresponding therapy can start. It is therefore important that you visit the doctor in any case, for example the family doctor, who will refer you to specialists, such as a pneumologist, if necessary.

If lung cancer is suspected, the anamnesis is usually followed

If the suspicion is confirmed, further examinations provide information on whether and to what extent the disease has already spread, i.e. whether lymph nodes are affected and whether metastases have formed. Ultimately, a biopsy ensures that the tumor is typed and the appropriate treatment can be started.

If coughing and lung problems persist after a corona disease, various examinations can provide clarity – whether and to what extent bronchial or lung tissue is impaired, chronic inflammation is present or allergic reactions promote shortness of breath. This includes, for example, a test of lung function with a bronchospasmolysis test, i.e. breathing with and without a bronchodilator drug.

Whether breathing difficulties are related to long-Covid or lung cancer can be clarified by appropriate diagnostics. There is no clear evidence that a cough, for example, actually comes from surviving corona disease. It is ultimately a diagnosis of exclusion. But this at least excludes other causes – such as lung cancer, but also COPD and asthma.