BackgroundCOVID-19 has impacted both society and medical care. While Germany entered the first lockdown in spring 2020, the PIKKO study (Patient information, communication and competence empowerment in oncology) was still active. The intervention modules, patient navigator (PN), services of the Saarland Cancer Society (SCS), psycho-social counseling and different courses, and online knowledge database (ODB) continued to be offered, but in an adapted form. It was the aim of this supplementary survey to identify the restrictions and burdens of the pandemic containment strategies on the PIKKO patients and thus on the PIKKO study itself. Furthermore, this work shows how the PIKKO modules were used during the lockdown.MethodsAll patients in the PIKKO intervention group (IG) were invited to complete a questionnaire, n = 503. Furthermore, utilization of the SCS and log files of the ODB were analyzed. For socio-demographic data and contacts with the PN, data from the regular PIKKO surveys were used. In addition to descriptive statistics, chi²-tests, F-tests and linear regression analyses were performed.Results356 patients participated in this supplemental survey. 37.6% reported restrictions. “Restrictions on accompanying persons”, “ban on visits to the wards” and “protective mouth-nose-mask” were reported as the greatest burdens. 39.0% expressed fears that the restrictions would have an impact on the course of their disease. Linear regression analyses showed differences in feelings of burden among age groups (more among < 60-year-olds), gender (more among women), children in the household (more with children), and preexisting financial stress (more with financial worries). In April 2020, there was more patient contact with PNs by phone, more SCS psycho-social counseling by phone, adapted SCS course offering, but with significantly fewer participants, and high activity on the ODB.ConclusionCancer patients in the IG reported restrictions from the pandemic containment strategies and feared an impact on their recovery. However, whether a burden is perceived as heavy depends more on gender, age, or pre-existing burdens than on whether the lockdown affects PIKKO or not. The utilization of counseling, courses or the ODB despite lockdown shows the need for such services, especially in times of crisis.Trial registrationThis study was retrospectively registered in the German Clinical Trial Register under DRKS00016703 (21 Feb 2019, retrospectively registered).https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00016703.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12885-023-10945-9.