Chemotherapy for Pancreatic Cancer

What is chemotherapy?

Chemotherapy (or chemo in short) is a type of treatment that uses cancer-killing drugs to stop or slow the uncontrolled growth of cancer cells. It can be used alone or in conjunction with other therapies like radiation therapy.

Chemotherapy for pancreatic cancer can be used in the following cases:

• Before surgery (known as neoadjuvant chemo) to shrink tumors that are too big to be removed surgically at the time of diagnosis, and improve the chances of resection
• After surgery (known as adjuvant chemo) to kill any remaining cancer cells that were not visible during the operation and subsequently left behind, thereby lowering the chances of the cancer coming back
• For advanced or metastatic cancers that cannot be removed completely with surgery (unresectable), where chemo can help to control tumor growth, shrink the pancreatic tumor and alleviate symptoms

Chemotherapeutics used to treat pancreatic cancer work by damaging DNA and disrupting the cell cycle in various ways. These types of drugs include:

Alkylating agents

Alkylating agents are a class of drugs that prevent cancer cells from dividing by damaging DNA directly. These drugs work in all cell cycle phases and are commonly used to treat numerous types of cancer. Examples of alkylating agents used for pancreatic cancer treatment include cisplatin and oxaliplatin.

Antimetabolites

Antimetabolites are drugs that interfere with DNA and RNA by acting as substitutes for the normal building blocks of these two biomolecules. As a result, cancer cells can no longer create copies of their genetic material and are thus unable to divide and form new cells. Examples of antimetabolites used to treat pancreatic cancer include 5-fluorouracil (5-FU), gemcitabine and capecitabine. If you are not healthy enough to take a combination of chemo drugs, you are likely to be prescribed any one of these antimetabolite drugs on its own.

Mitotic inhibitors

Also known as plant alkaloids, these drugs are derived from natural products such as plants. They inhibit the cell’s ability to divide and form new cells, a process called mitosis. They can also damage cells in all phases of the cell cycle by interfering with enzymes that make proteins needed for cell replication. Albumin-bound paclitaxel (or nab-paclitaxel) is a mitotic inhibitor used to treat pancreatic tumors.

Topoisomerase inhibitors

These drugs interfere with enzymes called topoisomerases, which separate DNA strands so that DNA can copy itself during the cell cycle. Disrupting the function of these enzymes prevents the cancer cells from dividing and also damages their DNA.

One topoisomerase inhibitor used for pancreatic cancer treatment is irinotecan. When encapsulated in a small, spherical vesicle called a liposome, it is known as liposomal irinotecan. This protects the drug from premature breakdown and allows it to reach the tumor more effectively.

Chemotherapy is administered by mouth (orally) or as an infusion into your veins (intravenously). The drugs then travel through the bloodstream to kill cancer cells throughout the body. This is known as systemic chemotherapy.

Your medical oncologist will administer chemotherapy in cycles, which consist of treatment sessions with periods of rest in between. Each cycle typically lasts for a few weeks. The frequency of your treatment sessions and the duration of your chemotherapy regimen may vary depending on the makeup of your pancreatic cancer and the drugs used. Your oncologist will also assess your body’s reaction to the drugs and may adjust the dosage and duration accordingly.

Typically given in an outpatient setting, each session can last from 30 minutes to a few hours, depending on the course of treatment. When it comes to intravenous administration, chemo drugs can be delivered in various ways, such as through a:

• Cannula: a short, thin tube inserted into a vein in your arm or the back of your hand
• Central line: a fine tube that goes under the skin of your chest and into a large vein by your collarbone
• Peripherally inserted central catheter (PICC) line: a fine, long tube that is inserted into a vein in your arm and goes up into a large vein in your chest
• Portacath: a small, implantable chamber that sits under your skin and is attached to a long tube going into a large vein in your chest

Chemotherapy drugs work by attacking cancer cells that are rapidly dividing. However, other healthy cells in the body that also divide quickly, such as hair follicles and those in the bone marrow, are likely to be affected. This can lead to side effects such as loss of appetite, mouth sores, hair loss, nausea and fatigue.

Your doctors will take into account several factors when deciding whether you should receive chemotherapy as part of your treatment plan. These include the type of pancreatic cancer you have, the cancer’s stage and other factors, like your overall health.

Chemotherapy can also take a toll on your body, so it is also important to take care of your mental and emotional health as you undergo this journey. You may find it helpful to seek support from friends and family, as well as resources provided by your cancer care team. They can provide emotional support, assist with daily tasks and offer a listening ear when you need it most. If you have any questions regarding chemotherapy, consult your doctors and cancer care team.