What are the main types of cervical cancer?

The two main types of cervical cancer are squamous cell carcinoma and adenocarcinoma. Cervical cancers are named after the type of cell where the cancer started.

Up to 90% of cervical cancers are squamous cell carcinomas. These develop from cells in the ectocervix, the outer part of the cervix. Adenocarcinomas develop in the glandular cells of the endocervix, the inner part of the cervix. The National Cancer Institute puts adenocarcinoma at roughly 10% of cases.

Sometimes cervical cancer has features of both types, which is called mixed carcinoma or adenosquamous carcinoma. Very rarely, cancer develops in other cells in the cervix.

Why the cervix has two kinds of cells at all

The cervix is the lower end of the uterus, opening into the vagina. Its outer surface is covered in flat, tough squamous cells, similar to skin. The canal running up into the uterus is lined with tall glandular cells that make mucus.

Those two surfaces meet at a border called the transformation zone. Cells there are always being replaced. That border is where nearly all cervical cancer begins. It is also what a Pap test aims at.

Why the split matters in practice

The two types are found in different ways. Squamous cell changes sit on the outer surface, right where a Pap brush sweeps. Glandular changes start higher in the canal. That tissue is harder to sample. So adenocarcinoma is the more likely of the two to slip past a Pap test.

That is part of why HPV testing now sits at the center of screening. An HPV test looks for the virus, not for abnormal cells. It does not depend on catching the right cells on a brush.

Outcomes may differ too, though the picture is not settled. NCI calls the question controversial. It notes that several studies found worse outcomes with adenocarcinoma, including more spread to distant sites.

The rare type worth naming

Small cell carcinoma of the cervix is uncommon. It is a neuroendocrine cancer, which is a different family of tumor from the two main types. If your report says small cell or neuroendocrine, ask your team what that means for your treatment. It is not the same situation as the common types.

Sarcomas and lymphomas of the cervix have also been reported, but they are rare.

Staging is separate from type

Type tells you what the cells are. Stage tells you how far the cancer has traveled. Cervical cancer is staged with the FIGO system. FIGO stands for the International Federation of Gynecology and Obstetrics. NCI calls it the most commonly used system, and the most accurate way to judge how far the disease has spread.

Both pieces feed the treatment plan. Neither one alone decides it.

What to do with this

Ask for a copy of your pathology report and find the line naming the cell type. If it says adenocarcinoma or small cell, ask what that changes about your plan.

Whatever the type, the cause is nearly always the same. It is a long-lasting infection with a high-risk HPV type. NCI notes that HPV 16 and 18 are the types most closely tied to high-grade cell changes and cancer. Your healthcare team can explain more about the type of cervical cancer in your situation.