Disorientated; in a lot of pain in his chest and rib area; in a lot of pain in his chest and rib area; hurt to breathe and move; shaken up; Short of breath/It hurt to breathe; Concomitant medication:ongoing prednisone for immunotherapy; Concomitant medication:ongoing prednisone for immunotherapy; This is a spontaneous report from a contactable nurse. A 93-year-old male patient (reporter's father) received first does of BNT162B2 (Lot#: EN5318), via intramuscular on 28Jan2021 10:00 at single dose for COVID-19 immunization. Medical history included ongoing prostate cancer metastatic diagnosed a few years ago and immunotherapy. Concomitant medication included ongoing abiraterone acetate (ZYTIGA) at 1g, once a day for prostate cancer and ongoing prednisone at 5 mg, tablet, twice a day, by mouth for immunotherapy. The caller stated she is reporting a reaction her father had to Pfizer's COVID-19 vaccine. The patient experienced disorientated, in a lot of pain in his chest and rib area, hurt to breathe and move and short of breath/it hurt to breathe on 29Jan2021. The reporter seriousness for the events was medically significant. The events didn't require a visit to emergency room or physician office. The patient did go to urgent care. The caller explained her father became disoriented. He received the first vaccine on 28Jan2021. The next day, her father began to move his car around 12 pm and he became disoriented and stated he wasn't going to drive. Caller stated they were not aware of this disorientation until Friday, 29Jan2021. Her father was not sleeping and was up the night before because he was in a lot of pain in his chest and rib area. It hurt to breathe. He was short of breath. It hurt to move. Caller clarified further her woke up feeling so bad he thought he was going downhill. He thought his cancer got worse over night. He told the caller's brother after he became so disorientated that he was no longer going to drive because he was so shaken up. He was taken to urgent care on Friday, 29Jan2021. He was prescribed Naproxen, 500 mg Friday evening and he slept all night for the first night in years. He usually gets up in the middle of the night to use the bathroom. He woke up on Saturday morning, 30Jan2021, and he was feeling 100% better. He recovered completely. He was up moving around and in no pain. Caller verified she has no NDC, Lot number and expiry date for the Naproxen her father was prescribed. She didn't see any of that written on the discharge papers, that may be with the pharmacy. She wanted to put a chest x-ray was done. He has Metastatic Prostate Cancer and the pain was coming from the lesions on his lung and rib. Caller explained the Chest X-Ray showed the mets (metastasis) but no new lesions, no infiltrates or anything. It showed nothing related to the COVID-19 vaccine.The patient underwent lab tests and procedures which included Chest X-ray: showed the mets (metastasis) but no new lesions, no infiltrates or anything on 29Jan2021 and EKG: essentially normal on 29Jan2021. The outcome of the events disorientated, in a lot of pain in his chest and rib area, hurt to breathe, shaken up and move and short of breath/it hurt to breathe was recovered on 30Jan2021. The reporter's assessment for all the events was related.; Sender's Comments: Based on the compatible time association, the contribution of suspect vaccine BNT162B2 to all events disorientation, chest pain, musculoskeletal chest pain, movement disorder, shaking, and shortness of breath cannot be excluded. The ongoing prostate cancer metastatic status and immunotherapy may be major cofounders. The impact of this report on the benefit/risk profile of the Pfizer product is evaluated as part of Pfizer procedures for safety evaluation, including the review and analysis of aggregate data for adverse events. Any safety concern identified as part of this review, as well as any appropriate action in response, will be promptly notified to Regulatory Authorities, Ethics Committees and Investigators, as appropriate.