Introduction

Immunotherapy is revolutionizing cancer care by transforming the way doctors treat several types of cancers, especially in the field of haemato-oncology. Unlike traditional treatments that directly attack cancer cells, immunotherapy helps the body’s immune system recognize and destroy them. This cutting-edge treatment is offering new hope to patients with blood cancers like lymphoma, leukemia, and multiple myeloma, as well as various solid tumors.

In this blog, we’ll explore how immunotherapy works, its types, its role in haematological cancers, benefits, side effects, and what the future holds.

What is Immunotherapy?

Immunotherapy is a type of cancer treatment that stimulates or enhances the body’s natural immune system to fight cancer more effectively. It involves either boosting the immune response or modifying it to better detect and eliminate cancer cells.

Cancer cells often evade detection by the immune system by producing certain proteins that turn off immune responses. Immunotherapy aims to block these signals and re-activate the immune system’s ability to target cancer.

How Does Immunotherapy Work?

The immune system is designed to detect and eliminate abnormal or foreign cells. However, cancer cells can sometimes hide or suppress immune responses through mechanisms such as:

• Producing immune checkpoint proteins like PD-L1
• Reducing expression of recognizable antigens
• Creating an immunosuppressive tumor microenvironment

Immunotherapy works by:

• Unblocking immune checkpoints
• Training T-cells to recognize cancer
• Using synthetic immune components like monoclonal antibodies or lab-modified T-cells

Types of Immunotherapy in Cancer Treatment

1. Immune Checkpoint Inhibitors

These drugs block proteins that stop T-cells from attacking cancer. Common targets include PD-1, PD-L1, and CTLA-4.

Examples:

• Nivolumab (PD-1 inhibitor)
• Pembrolizumab (PD-1 inhibitor)
• Atezolizumab (PD-L1 inhibitor)

Used in: Hodgkin lymphoma, melanoma, lung cancer, etc.

2. CAR-T Cell Therapy (Chimeric Antigen Receptor T-cell Therapy)

A personalized treatment where a patient’s T-cells are collected, genetically modified in a lab to recognize cancer cells, and re-infused into the body.

Examples:

• Axicabtagene ciloleucel (for B-cell lymphoma)
• Tisagenlecleucel (for acute lymphoblastic leukemia)

Used in: B-cell lymphoma, ALL, and multiple myeloma.

3. Monoclonal Antibodies

Lab-engineered antibodies that attach to specific proteins on cancer cells. Some act by flagging cancer cells for destruction; others block growth signals or deliver toxins.

Examples:

• Rituximab (targets CD20 in lymphoma)
• Daratumumab (targets CD38 in multiple myeloma)
• Alemtuzumab (targets CD52 in CLL)

4. Cytokine Therapy

Cytokines are signaling proteins like interleukins (IL-2) or interferons (IFN-α) that help boost immune activity.

These are now less commonly used due to newer, more targeted therapies but still play a role in certain cancers.

5. Cancer Vaccines

Unlike preventive vaccines (like HPV), cancer vaccines are therapeutic — designed to stimulate the immune system to attack existing cancer cells.

Example: Sipuleucel-T for prostate cancer.

Immunotherapy in Haemato-Oncology

Immunotherapy has had a particularly strong impact in the treatment of hematological cancers:

1. Hodgkin Lymphoma

• Checkpoint inhibitors like Nivolumab and Pembrolizumab are approved for relapsed/refractory Hodgkin lymphoma.

2. Non-Hodgkin Lymphoma (NHL)

• CAR-T cell therapy has shown significant results in large B-cell lymphoma.
• Rituximab, a monoclonal antibody, is standard in B-cell NHL.

3. Acute Lymphoblastic Leukemia (ALL)

• Blinatumomab, a bispecific T-cell engager, helps direct immune cells to leukemia cells.
• CAR-T therapy offers long-term remission in pediatric and young adult ALL.

4. Multiple Myeloma

• Monoclonal antibodies like Daratumumab and Isatuximab are game-changers in relapsed/refractory myeloma.
• CAR-T therapies like Idecabtagene vicleucel are approved for advanced cases.

How is Immunotherapy Given?

• Intravenous infusion is the most common route.
• Some monoclonal antibodies or checkpoint inhibitors are given once every 2–3 weeks.
• CAR-T cell therapy is a multi-step process, involving cell collection, engineering, and reinfusion.

Immunotherapy may be used alone or in combination with chemotherapy, targeted therapy, or stem cell transplantation.

Benefits of Immunotherapy

✅ Precision-based: Specifically targets cancer with minimal damage to normal cells

✅ Fewer side effects than conventional chemotherapy in many cases

✅ Long-term remission potential, especially in blood cancers

✅ Reactivation of immune memory may prevent recurrence

✅ Personalized approach based on the patient’s immune and genetic profile

Side Effects of Immunotherapy

Although often better tolerated than chemotherapy, immunotherapy can cause immune-related side effects, which happen when the immune system attacks healthy tissues.

Common Side Effects:

• Fatigue
• Fever or chills
• Skin rash
• Nausea
• Diarrhea

Serious Immune-related Complications:

• Pneumonitis (lung inflammation)
• Colitis (inflammation of the colon)
• Hepatitis
• Thyroid dysfunction
• Neurological issues (rare)

Most of these are manageable with steroids or immunosuppressive medications if detected early.

Who is Eligible for Immunotherapy?

Eligibility depends on several factors:

• Type of cancer
• Stage of disease
• Presence of specific markers (like PD-L1 expression, CD19, CD20, CD38)
• Overall health and ability to tolerate immune responses

Molecular and immune profiling of the tumor helps determine the right immunotherapy for each patient.

Monitoring During and After Immunotherapy

Patients undergoing immunotherapy need regular:

• Blood tests (to monitor organ function and immune markers)
• Imaging (to assess tumor response)
• Monitoring for autoimmune side effects

Unlike chemotherapy, response to immunotherapy can sometimes take weeks to months, and tumors may appear larger before shrinking — a phenomenon called pseudoprogression.

Immunotherapy vs. Chemotherapy

FeatureChemotherapyImmunotherapyMechanismKills fast-dividing cellsStimulates immune systemSpecificityNon-specificTargeted at immune checkpoints or antigensSide EffectsNausea, hair loss, infectionsImmune-related reactionsDuration of ResponseOften shorterCan be long-lastingEligibilityBroadSelected patients with biomarkers

Future of Immunotherapy

Research in immunotherapy is growing rapidly. Areas of focus include:

• Bispecific antibodies that can engage two targets simultaneously
• Checkpoint inhibitors in combination with chemotherapy or targeted therapy
• Neoantigen vaccines personalized to each patient’s tumor
• Off-the-shelf CAR-T products for faster availability
• Gene editing technologies (like CRISPR) to enhance immune cell function

As our understanding of cancer immunology deepens, newer and safer immunotherapies will likely become standard in cancer care.

Conclusion

Immunotherapy has transformed the landscape of cancer treatment, offering hope where few options once existed. It is particularly impactful in hematologic cancers like lymphoma, leukemia, and myeloma. By harnessing the power of the immune system, immunotherapy enables the body to fight cancer in a more intelligent, targeted, and long-lasting way.

While not every patient may be eligible, and challenges like immune side effects and resistance remain, the potential of immunotherapy is immense. With ongoing research and innovation, the future of cancer care is brighter — and more personalized — than ever before.