Worried about getting CIN because it can transform into cervical cancer?

HPV isn’t the only risk factor. So is smoking. And there’s specific reasons for this.

In 2004 the International Agency for Research on Cancer announced that smoking can lead to cervical cancer.

CIN is a precursor to cervical cancer. CIN stands for cervical intraepithelial neoplasm, aka cervical dysplasia).

This is a pre-malignant condition that’s devided into three grades: I, II and III (or 1, 2 and 3).

CIN can go from grade I to grade III without any symptoms. Before a woman knows it, that III can undergo the final transformation into cervical cancer — which has a five-year overall survival rate of 66%.

“CIN 1 has only a 40% chance of becoming cancer, while CIN 2-3 have a 60% chance,” says Betsy Greenleaf, DO, a board certified urogynecologist and owner of Greenleaf Health & Wellness, a medical center dedicated to mind-body-spirit wellness.

“There are many factors that can cause these changes in the tissue with human Papilloma virus (HPV) being the biggest cause,” says Dr. Greenleaf.

Smoking increases the risk of cervical cancer through four patheways:

• A toxic effect directly onto cervical tissue

• Suppression of cervical-region immunity

• Suppression of entire immune system

• Unhealthy lifestyle associated with smoking

Toxic Effect of Smoking

“Of course, many people think of lung cancer as a risk of smoking and most people wouldn’t smoke if they thought they could get cancer,” says Dr. Greenleaf.

“The majority of people think, ‘It won’t happen to me.’ What people don’t realize — especially women — is that we have nicotine receptors in other areas of the body that increase our risk of cancer.

There are nicotine receptors in the bladder and the cervix. As a smoker one activates these receptors and can trigger abnormal processes in the DNA that lead to cancer.”

Double Whammy: Smoking Plus HPV

“Even if these changes are initially caused by a virus, activation of these cells through smoking drastically increases the risk,” explains Dr. Greenleaf.

“Those who smoke have a 55.7% chance higher risk of developing cervical cancer.”

What about secondhand smoke?

“For every 13 people who are exposed to secondhand smoke who don’t develop cervical cancer, 22 people will develop cervical cancer,” notes Dr. Greenleaf.

“This is a considerably high rate. So you are who you hang out with.”

What’s even more troubling about all of this is that many women do not get regular Pap smears — the premier screening procedure for CIN — catching it before it turns into cancer.

The Pap smear is the golden standard for collecting a CIN sample so that it could be biopsied.

Quit smoking, and you’ll never have to worry about this causative agent for cervical intraepithelial neoplasm.

Dr. Greenleaf is board certified in obstetrics/gynecology, female pelvic medicine and reconstructive surgery, and procedural medicine and aesthetics. She is host of Some of Your Parts Podcast and owner of the Pelvic Floor Store. Follow her on Instagram.
Lorra Garrick has been covering medical, fitness and cybersecurity topics for many years, having written thousands of articles for print magazines and websites, including as a ghostwriter. She’s also a former ACE-certified personal trainer.  
Su B, Qin W, Xue F, et al.
The relation of passive smoking with cervical cancer: A systematic review and meta-analysis. Medicine (Baltimore). 2018;97(46):e13061