The COVID-19 pandemic impacted the German healthcare system comprehensively. It is being widely discussed whether there was also a negative effect on cancer care, but evidence to quantify such an effect is lacking. This analysis aims to investigate the pandemic impact on the detection and management of breast cancer (BC), colon cancer (CC), lung cancer (LC), and prostate cancer (PC) in Germany. The analysis was based on anonymized claims data from a German statutory health insurance (AOK PLUS). Incidence was defined as at least one inpatient or two outpatient diagnoses of one of the four cancer types after a 24-month pre-index period without any cancer diagnoses. Standardized cumulative incidences and the proportions of patients with a metastatic diagnosis within the first three months after incident diagnosis were compared between 2019 and 2020. Differences in the time to treatment initiation (surgery, radiation, or systemic anticancer treatment) between 2019 and 2020 were investigated using Kaplan-Meier estimation. The standardized cumulative incidence of BC, CC, and LC in 2020 were significantly lower compared to 2019 (BC: 0.040%/0.038%; CC: 0.045%/0.037%; LC: 0.028%/0.025%; all p<0.001), while similar incidence of PC was observed (0.036%/0.036%; p>0.001). In all groups, the proportion of patients with metastases at the time of incident diagnosis did not differ considerably between the years. The time to treatment initiation after incident diagnosis did not differ significantly between 2019 and 2020 in the investigated populations. In incident BC/CC/LC/PC patients, the median time to therapy start was 42/47/59/90 days in 2019 versus 40/47/56/94 days in 2020 (HR [95%-CI]: 1.01 [0.92-1.10]/1.02 [0.92-1.3]/1.06 [0.94-1.20]/0.97 [0.88-1.07]). Significantly fewer patients were diagnosed with BC, CC, and LC in 2020 compared to 2019, possibly due to lower cancer screening rates. However, cancer therapy initiation and timing in newly diagnosed patients in 2020 were not substantially different from the pre-pandemic year.