Pain under arm

I had surgery in October and radiotherapy in January of this year to my left breast. For a couple of weeks I have been getting gradually worse pain under my arm and around the scar area of my breast. It seems spongy… a little swollen. I have tried contacting my breast care team and GP but I’m having difficulties with this and I’m worried. The pain feels sore and pain to touch. I feel like I have no energy. I wondered if you had any idea if this is normal or not? Karen

Hi Karen, 

From my experience I would say yes it’s normal, someone once told me that apparently radiotherapy carries on working months after the actual treatment has finished… no idea if this is true but it kind of makes sense. Radiotherapy can cause a lot of internal tissue damage and changes, and it will take a long time for it all to heal. It’s been nearly 3 years since my lumpectomy and radiotherapy and I still have a lot of discomfort in the breast, armpit and collarbone area. My left breast is slightly firmer than the other one and is tender to touch. 
Of course get it checked out if it’s worrying you… I’ve done that quite a few times and I’m always told it internal scar tissue from surgery and fibrosis caused by the radiation.


Hello Karen

Thanks for your post. It’s understandable you want to know if the recent pain and swelling you have under your arm and around the scar area is normal after surgery and radiotherapy

Pain can sometimes occur several months after treatment has finished and may be caused by different things, such as scar tissue or nerve damage after surgery, or by the effect of radiotherapy as @Blackcat182 says. 

As you mention this pain and swelling has recently developed, we would suggest trying to contact your treatment team or breast care nurse again. They can assess the area affected to find out the possible cause and suggest ways to help improve the pain you have. 

Feeling tired and like you have no energy is common after treatment for breast cancer. This can be related to treatments such as radiotherapy but also to the emotional impact of having a breast cancer diagnosis. You might find these tips on managing fatigue of help. You can mention the tiredness to your treatment team or breast care nurse when you speak to them. They may want to take a blood test to check for causes, such as low iron levels, and can also let you know about any local support services available to you. 

We offer a range of free supportive services for anyone who has had a diagnosis of breast cancer which you may be interested in.  They include face to face and online courses and events. For more details about all of these services, please see the information on the link. 

We are currently evaluating this service and would appreciate your feedback. Please click here to the survey. It should take approximately 10 minutes to complete.  

Do call our helpline if you would like to talk this through or have any further questions. The helpline team have time to listen to your concerns, talk things through and signpost you to more support and information. Your call will be confidential, and the number is free from UK landlines and all mobile networks. The number is 0808 800 6000, (Relay UK -prefix 18001). 

If you would prefer one of our nurses to call you. To do this, please complete this form ticking the box agreeing to a call back.  

Our usual opening hours are Monday to Friday 9am - 4pm and 9am -1pm on Saturday.  

Out of hours you can leave a message and we will call you back when we next open.  

Best wishes 


Breast Care Nurse 

Please read the Ask Our Nurses disclaimer  Full details on how we collect and use your data can be found in our Privacy Policy  

This thread will now be closed from further replies. If you have any additional questions or would like to provide feedback, please start a new thread.