Dr. Peter F. Schnatz commented in an email that his group has shown that women with AGC have a higher likelihood of having some kind of malignancy (between 3% and 5%). “While the majority of the malignant cases are endometrial in origin, many can be extrauterine malignancies, including both colon and breast cancer,” he told Reuters Health.
However, he added, “Whether there is a direct link between AGC and breast cancer, to our knowledge, has not been studied previously.”
To look into that point, Dr. Schnatz, of The Reading Hospital and Medical Center, Pennsylvania and colleagues analyzed data on 470,147 Papanicolaou test results from a single hospital over a 7-year period. There were 1087 cases of AGC in 1026 women, and these were compared with 1064 women whose Pap tests were negative for AGC.
“Of the women with AGC, 40 (3.9%) had a breast disease, compared with 21 (2.0%) women with breast disease in the control group who had no AGC (p=0.009),” the investigators found. Breast disease was defined as any invasive or in situ lesion, including a ductal or lobular carcinoma in situ as well as an invasive ductal, lobular, mixed or unspecified carcinoma.
Two-thirds of the 40 breast cancers occurred before the AGC finding, while most that occurred after the Pap test did so within 35 months.
Among the 40 women with breast disease and AGC on their Pap test, 7 (17.5%) also had a concerning gynecologic pathologic finding; i.e., a cervical or endocervical squamous intraepithelial lesion (SIL); a cervical, endocervical, or endometrial malignancy; or endometrial hyperplasia. In comparison, the women with normal Papanicolaou test results had no such findings.
When the cases of gynecology pathology, which could explain the AGC, were excluded, the association of AGCs with breast disease was still significant (p=0.025).
The nature of the relationship between AGC on cervical cytology and risk of breast and gynecologic malignancy is still unclear, the researchers say. Nonetheless, even if an explanation is found, the association “supports the need for age-appropriate cancer surveillance (colonoscopy and mammography), particularly in women with an AGC on Papanicolaou testing.”
Dr. Schnatz concluded, “It is certainly something practicing physicians should be aware of, mostly to emphasize the high risk associated with AGC in general. While there is not enough evidence to recommend changes to the current comprehensive evaluation for AGC Pap smears, people should be aware of the association.”
The association of breast disease and atypical glandular cells on cervical cytology