The breast cancer was found 3 weeks ago/ has cancer in her left breast and has had surgery; This is a spontaneous report received from a contactable reporter(s) (Consumer or other non HCP) from medical information team. The reporter is the patient. A 78-year-old female patient received BNT162b2 (BNT162B2), on 17May2022 as dose 4 (booster), single (Lot number: FM7553) at the age of 78 years, in left arm for covid-19 immunisation. The patient's relevant medical history included: "Arthritis in knees", start date: 2021 (unspecified if ongoing), notes: Arthritis in knees diagnosed last year; "Cholesterol" (unspecified if ongoing); "Low vitamin D3" (unspecified if ongoing), notes: Low vitamin D3, dietary Vitamin D supplement; "Acid reflux" (unspecified if ongoing), notes: Acid reflux; "Blood pressure" (unspecified if ongoing). The patient's family history included: "breast cancer" (unspecified if ongoing), notes: Her aunt at 80 something had breast cancer on her fathers side, her fathers sister, cousin on husbands side; "heart attack " (unspecified if ongoing), notes: her dad had a heart attack ; "stroke " (unspecified if ongoing), notes: her mom had a stroke at 93. Concomitant medication(s) included: SIMVASTATIN taken for blood cholesterol (ongoing); NATURE MADE VITAMIN D3 taken for vitamin d deficiency (ongoing); REPLESTA taken for vitamin supplementation, start date: Jul2022; PANTOPRAZOLE taken for gastroesophageal reflux disease (ongoing); LOSARTAN taken for blood pressure measurement (ongoing). Vaccination history included: BNT162b2 (Dose#1 on 02Mar2021 lot EN6203 left arm), administration date: 02Mar2021, when the patient was 76-year-old, for COVID-19 immunization; BNT162b2 (Dose#2 on 25Mar2021 lot ER8730 left arm, she had a heart murmur last Apr2021), administration date: 25Mar2021, when the patient was 77-year-old, for COVID-19 immunization, reaction(s): "heart murmur"; BNT162b2 (1st booster Pfizer adult. Lot FF2587 left arm on 19Nov2021), administration date: 19Nov2021, when the patient was 77-year-old, for COVID-19 immunization; Flu shot (she may have gotten her flu shot in her right arm, but isn't sure.), administration date: Oct2021, when the patient was 77 years old, for Immunization. The following information was reported: BREAST CANCER FEMALE (medically significant) with onset Sep2022, outcome "unknown", described as "The breast cancer was found 3 weeks ago/ has cancer in her left breast and has had surgery". The patient underwent the following laboratory tests and procedures: Biopsy breast: (unspecified date) Result unknown; Electrocardiogram: (Sep2022) Fine, notes: EKG before surgery and that was fine; Pictures: (2021) Unknown results; Magnetic resonance imaging: (Sep2022) Fine; Mammogram: (2021) there was nothing; (Jul2021) Fine, notes: Her mammogram last Jul2021 was fine, it said she has dense breasts but didn't show anything and she has always had dense breasts; (Sep2022) Breast cancer, notes: The breast cancer was diagnosed 3 weeks ago with mammogram; Ultrasound breast: (Sep2022) Unknown results; Ultrasound scan: (2021) Unknown results. Therapeutic measures were taken as a result of breast cancer female.  Additional information: It was reported that the patient had 4 doses. She is calling about regarding the "last one" they are "talking about". She has not gotten this one yet. She has left sided breast cancer and she has received all 4 doses in her left arm. She wants to know has this been reported and has this been reported. Wanting to know if we have any information pertaining to this. She mentioned if other people have reported that then we may need to not put it in the arms. Caller notes that she is worried about getting the booster. 78-year-old female patient. She wants to know if breast cancer has been reported after having the vaccine, the breast cancer was found 3 weeks ago. Caller notes there is "a cousin on husbands side, not blood related to her. She had to have both of her breasts removed years ago because of the trait with all women in the family. She had Pfizer shots in left arm, all in the same arm and turns out something in her breast expanded, what ever else was left in there. Clothes too tight. No more shots in her arm.  She had to find a place to give her booster in her behind. Thought this is something important. What needs to be done, for all of you to call, any breast docs and surgeons to see if you can find when this is happening, is it after the shots were given. Do they get breast cancer after the shots had it been in the other arm but since all 4 shots were in the left arm. This is the reason I am calling. I want them to call around and check not wait on others to call because they may not think to call. Something doesn't seem right here. out of the clear blue sky appreciate stuff your doing so we don't get the virus. Maybe give them in our butts, back in the day we did, our kids did and then a maybe we wont have the breast stuff  I have to have three removed where I had the shot. surgeons on all breast docs need to ask questions, hey are you seeing influx of breast cancer with patients who have had their shots. It worries me. 78 never had any problems and no family hx, wow why did this happen, and in my left arm, that is what is concerning. I don't want anyone else to go through this.  Need to know if they can give it in another part of the body. I had all of mine at a hospital, (Hospital name withheld), not just (Pharmacy name withheld) or (Pharmacy name withheld), went to medical place because I wanted to be sure I was getting it right. I want them to do some checking. When they test people for years, asking people and doing something, this is something. I would like to hear from someone to see if they have heard about this. Even if its one and 2. I want them to talk among themselves. I hope someone will call me back. On 27Sep2022 the caller further clarified that she is 78 and has had all the vaccines except the last one they are talking about. States she waits 6 months before getting another one. Has never had problems with illness. Went for a mammogram last year and there was nothing. She now has cancer in her left breast and has had surgery and is waiting to have radiation. She had all her shots in her left arm. Her cousin by marriage, all her family has to have their breasts removed. She got all her shots in her left side only and it's starting to swell and her clothes are tight and her doctor doesn't want her to get any more shots in her arms, only in her behind. The patient has no family history of cancer (as reported), why all of a sudden this is going on she feels we need to know. Are there other people that are saying this? She's supposed to get the flu shot and doesn't know where to go with that, she won't do her left arm and doesn't want the next booster they are offering and doesn't know where it's going to go in her body. When asked for the Primary / Prescribing Healthcare Professional Info: Declines. Doesn't know who to put on, she has an internist and now a surgeon that did her breast cancer. Her mammogram last year was fine, she is really questioning all of this.  The breast cancer was diagnosed 3 weeks ago with mammogram. They took out nodules under her armpit at the end of her left breast and took out the cancer right at the nipple and the 3 nodules or nodes. That was done last Wednesday, 21Sep2022.  She has a doctor appointment with her surgeon on Monday to get the results and see how many treatments of radiation she will need. Her mammogram last Jul2021 was fine, it said she has dense breasts but didn't show anything and she has always had dense breasts. For the concomitant medication: None (as reported), just what she has been taking all along for cholesterol, blood pressure, and acid reflux. She has been on these for years and has nothing new. Doesn't take medication unless needed. They wanted to give her morphine after surgery and she said she didn't want to. Investigations: States they did an EKG before surgery and that was fine. They thought she had a heart murmur last Apr2021 and she had a workup that was perfect. The did pictures, ultrasounds and put dye through her and she knows she is ok on all that. Had an MRI to see if her other breast is ok and that is fine that was just a week before the surgery. They wanted to see what they are dealing with. Also had an ultrasound before the MRI where they took a biopsy of her left breast. The event did any not require a visit to emergency Room but visited Physician Office. The patient prior Vaccinations (within 4 weeks): was none. The last flu shot was Oct2021. The more she is thinking she may have gotten her flu shot in her right arm, but isn't sure. Someone told her to get it in the arm you use so it doesn't hurt and man that thing hurt. Caller does not have manufacturer, vaccine name, NDC, lot or expiry to provide. States that someone told her they use smaller needles for the vaccine and use a different size for the flu shot but doesn't know if that is true. The patient wants to know if other people have had this and if yes then stop putting it in the arm. It is weird that she got it in her left arm and has left side breast cancer and she is scared to death to get another and doesn't want a part of that. Has never had COVID thank goodness. We should put out a thing and ask other people that might not associate or think of it. It's been out 2 years now in peoples bodies and who knows. We should contact all the doctors offices and women with breast cancer and see how many show up with breast cancer after getting it and what arm they got it in and what side the cancer is in. Thinks we will find out something not good with this.  Follow-up attempts are completed. No further information is expected.