The SARS-CoV-2 pandemic has significantly impacted cancer patient management. National and local recommendations to reduce SARS-CoV-2 transmission have been applied in a comprehensive cancer center located in Northern France. We prospectively measured key indicators for three successive eight-week periods: directly before, during, and right after the containment (from 16 March to 10 May 2020). Overall, the number of newly diagnosed and referred cancer patients in our hospital steadily increased (1027; 1135 and then 1704; +11% during containment and +50% just after). To reduce patient transportation, teleconsultations were implemented. Teleconsulting activity steadily increased during the three periods (5, 2025, and 2351). However, a marked decrease in the number of surgical procedures was observed (448; 330 and 288; -26% during containment and -13% just after). We observed a slight decrease in the number of radiation therapy sessions (7761; 7328 and 7075; -6% during containment and -3% just after) and in day-hospital cycles of IV systemic treatment (2891; 2736 and 2717; -5% during containment and -1% just after). We observed an increase in the number of patients admitted to palliative care and a dramatic reduction in clinical trial enrollment. During this 24-week period, organizational changes were mainly characterized by an increase in newly diagnosed cancer patient referral and the implementation of protective measures, such as teleconsultations. Activities in cancer surgery have decreased while radiotherapy and chemotherapy activities were stable.