Cancer diagnosis and treatments- brief overview of the changing paradigm. Pranshu Bansal MD New Mexico Cancer Center
Identifying cancer in clinic Most common cancers are lung, breast, colon, prostate and cervical. Screening available for all these cancers Basic screening guidelines should be followed Other indicators include unexplained anemia, chronic fatigue, weight loss etc. Diagnosing any of the common cancers at an early stage leads to long survival.
Main treatment options for cancer Surgery Radiation therapy Systemic therapy 1) Chemotherapy 2) Targeted therapy 3) Immunotherapy
Fast evolving field
Chemotherapy- basics
Chemo settings Neoadjuvant- prior to surgery- goal is cancer cure Adjuvant- After surgery- goal is prevention of cancer recurrence Palliative- When cancer is widespread and goal is to prolong life and improve quality of life
Selecting chemotherapy based on efficacy and toxicity Cells of the bone marrow and GI tract are the most sensitive to the narrow therapeutic window Although some s/e like diarrhea, hair loss and increased risk of infection are common. There are specific side effects to each chemotherapy Adriamycin- cardiotoxicity (baseline ECHO) Vincristine, Oxaliplatin- Neuropathy (Prior H/O DM) Cisplatin- Kidney toxicity, ototoxicity (Age) Alimta- Allergic reaction (Patient education)
Chemotherapy- Administration Usually chemotherapy is administered in cycles which usually (Once every 2 or 3 weeks) Patients are seen in clinic prior to every chemo and toxicity assessment is performed Usually chemotherapy are given in combination of 2 or more drugs Combination chemo is usually continued for 4-6 months and after that a switch to single agent is made if the patient is responding.
Chemotherapy- activity and resistance Some cancers are more chemosenstive- colon cancer is treated with FOLFOX has a response rate of >50%, testicular cancers respond very well to cisplatin with >90% response rate However resistance to chemotherapy eventually develops and thus requires either a change in treatment plan to an alternative regimen Mechanism of resistance can include
Targeted therapy basics The first targeted therapy to receive FDA approval was tamoxifen in 1970 Targeted therapies work very well in certain cancers where the target is gene mutation that s driving the cancer growth Imatinib is a targeted therapy for CML which results in response in >70% patients for >5-7 years Lung cancer in non smokers can frequently have a driver mutation that can be targeted (>10 cancer drugs in lung cancer targeting genes have been approved)
Targeted therapy administration Mostly targeted therapies are oral pills, some can however be IV drugs given every 3 weeks They can be efficacious by themselves or may sometimes be combined with chemotherapy When combined with chemotherapy they allow the benefit of possibly increasing the response rate without adding a lot of toxicity
Targeted therapy side effects Skin toxicity is a common side effect with a lot of targeted agents (rashes, dryness) Others can have unique side effect profile based on the target VEGF inhibitors can cause HTN and bleeding BRAF inhibitors can increase risk of skin cancers
Cancer Immunotherapy In the News
Immunotherapy- basics There is a lot of hype in oncology over the potential of immunotherapy The basic premise is to make the body s own lymphocytes recognize the cancer cell as a foreign entity and try to kill it This can be achieved in myriad of ways and some FDA approved drugs include checkpoint inhibitors and CAR-T cells
Checkpoint inhibitors Pembrolizumab, nivolumab- PD-1 inhibtors Avelumab, Durvalumab- PD-L1 inhibitors
Immunotherapy- administration Usually given once every 2 or 3 weeks Continued till disease response Usually well tolerated
Immunotherapy- side effects Immune related adverse effects Colitis- diarrhea Pneumonitis- cough/sob Hypothyroidism Hypophysitis Adrenal insufficiency Fatigue
Post treatment surveillance Surveillance is guideline driven and is different for every cancer Colon cancer patients usually require follow up colonoscopy in 6 months to 1 year Lung cancer patients need follow up CT scans of chest Prostate cancer annual PSA check Testicular cancers every 3-6 month tumor marker check Breast cancer patients annual mammogram
Cancer survivors- common symptoms Fatigue Depression Anxiety Fertility counseling Neuropathy Genetic counseling