The symptoms of COVID-19 and SCLC do have some overlap. Some examples of symptoms that may happen with either condition are:
cough
shortness of breath
fatigue
However, COVID-19 and SCLC also have unique symptoms as well. For COVID-19, these may include a runny or stuffy nose, a sore throat, or the loss of smell or taste. For SCLC, they may include chest pain, hoarseness, or unexplained weight loss.