Targeted Therapies in Cancer Management - Health Education - DesiMD Healthcare - India

Targeted Therapies in Cancer Management

Dr.K Madhava profile Authored by Dr.K Madhava on 5 Jan 2015 - 13:27.

Targeted therapies are currently the focus of anticancer drug development and considered to be an important component of systemic therapy in cancer. They are emerging as corner stone in development of personalized therapy, a form of medicine that uses information about person's genes and proteins to prevent, diagnose and treat cancer.

Targeted therapies are drugs or other substances that block the growth and spread of cancer by interfering with specific molecules that are involved in the growth, progression and spread of cancer. These are sometime called molecularly targeted drugs or precision medicine. They differ from standard chemotherapies in several ways. Targeted therapies act on specific molecular targets that are associated with cancer, where as most standard chemotherapies act on all rapidly dividing normal and cancerous cells.

Most targeted therapies are either small molecules or monoclonal antibodies. Small molecule compounds typically developed for targets that are located inside the cell because such agents are able to enter cells relatively easily. Monoclonal antibodies are relatively large and can’t enter cells. They are used only for targets that are outside the cells or on the cell wall.

For some drugs and certain cancers there are specific marker tests available to check if any of the targeted drugs would work in those patients. These tests are done from patient’s tumor sample or blood test. Examples are HER2 testing in breast cancer, EGFR testing in lung cancer and K-RAS testing in colon cancer.

Some targeted drugs are used more commonly than others and some drugs work in more than one type of cancers.

Most popular antibody therapies in use are:

  • Transuzumab used in breast cancer,
  • Rituximab used in lymphomas,
  • Cetuximab in head & neck cancer and colon cancer and
  • Bortezomib in Myeloma patients.

Very popular small molecule drugs are Erlotinib in lung cancer and head and neck cancers, Gefitinib in lung cancer, Sunitinib, Sorafenib and Pazopanib in kidney cancer,  Sorafenib in liver cancer and Imatinib in Leukemia & GIST tumors.

Many new small molecular drugs can be administered orally on daily basis from home. Generally these drugs can be given to patients who are less fit and considered unsuitable for chemotherapy because of poor general condition.

Although many of these drugs are more expensive when newly introduced, gradually prices come down making it accessible to all.

Certainly with the establishment of targeted therapy as anti-cancer treatment, we are heading for an exciting era with unlimited future potential for cancer prevention and control, helping patients particularly with certain cancers that do not have any established treatment.

Restoring Hope

A 55 year old postmenopausal lady, doctor by profession, noticed a lump in her left breast since 3 months. Mammogram, ultrasound and core biopsy confirmed malignancy, ER/PR+ve, Her-2 +ve.

PET-CT scan showed there was no spread to other organs.She received 4 cycles of chemotherapy before and four cycles after the surgery (breast conservation surgery)

Her-2 is an epidermal growth factor. Amplification of this oncogene has shown to play an important role in development and progression of certain aggressive types of cancers. 30% of breast cancer patients have Her-2 positive. Trastuzumab is a targeted therapy drug known as a monoclonal antibody.  It attaches to Her-2 and can help to slow the growth of cancer cells with too much Her-2. It may stimulate the immune system to more effectively attack the cancer.

She received injection Trastuzumab once in 3 weeks, for 1 year, even during her radiotherapy.It has been two years since she completed her cancer treatment.Regular follow up once in 3 months and PET CT scan after a year showed that she was incomplete remission.

 

 

 

*Disclaimer
*Disclaimer: This is not medical advice. The content is for educational purposes only. Please contact your doctor for any health care issues.