Little is known about what uncertainties patients experience after being identified to carry a pathogenic variant in a moderate-risk cancer gene as a result of undergoing multigene panel testing for cancer susceptibility. Data regarding cancer risk estimates and effectiveness of risk management strategies for these variants continues to evolve, which has the potential to evoke uncertainty. Acknowledging uncertainty during pre-and post-test discussions is imperative to helping individuals to adapt to their results. A better understanding of this population's experience of uncertainty is needed to facilitate such discussions and is the aim of the current study. Semi-structured interviews (30-60 min in length), informed by Han and colleagues' taxonomy of uncertainty in clinical genomic sequencing, were conducted to assess motivations to pursue genetic testing, areas of perceived uncertainty, and strategies for managing uncertainty among 20 carriers of pathogenic variants in two moderate-risk genes, ATM and CHEK2. We found that participants pursue genetic testing with the expectation that results will clarify cancer risks and approaches to management. Participants experience uncertainties aligning with Han's taxonomy relating to the ambiguity of specific cancer risk estimates and effectiveness of certain risk management strategies. These uncertainties influenced decisions around the uptake of risk management strategies, which were additionally impacted by clinicians' uncertainty towards such strategies. Participants employ a variety of uncertainty management approaches to cope with their anxieties. Clinicians may wish to use these findings to facilitate patient adaptation to the implications of multigene panel testing for cancer susceptibility during both pre-and post-test counseling sessions.