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Date of last update: 10/21/2017.

Forum Name: Miscellaneous Cancer Topics

Question: Mass popping out under left rib..sometimes right?

 Sweetheart5015 - Sun Mar 02, 2008 3:24 pm

Hi there..I am a 21/f and 13 wks pregnant with my second child. Ive had on/off left side chest pain for about 6 months now and had a normal chest xray in september and multiple blood tests that have mostly been pretty normal. a few weeks ago, i noticed the chest pain under my left rib that goes around to my back and when i move a certain way or bend up/down, i feel something "popping" in and out at the bottom. It isnt painful and I can actually feel it if i put my finger there and pop it back in. It doesnt feel like a mass necessarily but a bone or something horizontal? i went to the ER for this last week and they said it was probably a floating rib but wouldnt do a scan/xray on me because i am pregnant. I just noticed today that the same thing happens occasionally, but not as prounounced, on the right side.

My father died of lung cancer in Oct 07 at 54 years old, and I am just so concerned now that this could be a tumor or that I could have cancer??

Could you please advise on what you think of this?
 Dr. A. De la Guerra - Mon Mar 03, 2008 11:54 pm

User avatar Hi Sweetheart5015,

While it is impossible to be absolutely sure without a physical examination, it seems very improbable a diagnosis of cancer with your symptoms. Rib discomfort is common in pregnancy. There are several reasons for this; I will explain some of them.

During pregnancy, the diaphragm rises by 4 cm and the chest circumference increases by 5–7 cm. These chest wall changes are attributed to the enlarging uterus that pushes up and tightens the diaphragm, this force is transmitted to the lower rib cage. In addition, hormonal changes cause relaxation of ribs ligaments. As a result the rib cage widens to accommodate the growing baby. These changes take place usually in the third trimester. Common complains are rib pain, caused from direct pressure to the chest wall with intercostal nerve irritation, less frequently due to rib subluxations. Also, some shortness of breath is common because of a reduced capacity of lung volumes.

Less known is the fact that changes in the chest occur before uterine enlargement, early during the first trimester. The subcostal angle can increase from 68 to as much as 103 degrees, which makes the ribs more flat. This could explain why you do not feel a mass but a bone or “something horizontal”.

The doctor at the ER may be correct about the floating rib. If you still have concerns about your symptoms seek advice from your doctor, he can order a high-resolution sonography, a useful way to characterize rib lesions.
 Sweetheart5015 - Fri Mar 07, 2008 3:42 pm

Thank you very much..
Well I visited my primary care doctor today and he felt it...i have the popping out on the left side under the ribcage when i move and then the pain/tenderness follows all the way around to my back. It's very annoying : / He wasnt very concerned (as i find he usually isnt) and is suggesting that this is most likely a slipped rib/floating rib or costochondritis? So he is sending me to the Chiropractor on Monday. Should I have requested a sonogram of the area? I am so worried that this isnt a rib and that something inside could be causing it (tumor..some other type of mass?)
Can you advise?
Thanks so much.

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