Is targeted therapy the same as chemotherapy?

No. Chemotherapy broadly attacks fast-dividing cells; targeted therapy is aimed at a specific molecule or genetic change the cancer depends on, so it can spare more healthy cells. It still has side effects, just a different set.

Why does my tumour need to be tested first?

Because a targeted drug only works if the cancer actually carries the target it’s designed to block. Biomarker (molecular) testing checks for the relevant gene changes or proteins, so treatment can be matched to your particular cancer.

Are the side effects milder than chemo?

Not necessarily milder – different. Severe hair loss and big drops in blood counts are less typical, but targeted drugs can cause skin rash, diarrhoea, raised blood pressure, liver changes and fatigue, and need monitoring.

Will targeted therapy keep working forever?

Often it works for a period and then the cancer adapts and stops responding – this is called resistance. If that happens, your team will discuss switching to another treatment.

Can everyone have targeted therapy?

No. It depends on whether your cancer has a targetable change, which is why testing is done first. Not every cancer has one, so it’s one option among several rather than a universal treatment.

Targeted Therapy for Cancer Singapore

Written & reviewed by the BestDoctors.sg editorial team · Last updated 1 Sep 2026 · General information, not medical advice

Quick answer. Targeted therapies are cancer drugs that home in on specific molecules or genetic changes that a particular cancer depends on to grow, making them more selective than traditional chemotherapy. Whether one can be used usually depends on testing the tumour for the relevant target – the basis of what’s often called personalised or precision cancer treatment.

Facing a cancer diagnosis, or worried about a symptom?

Message our care team on WhatsApp. Tell us what’s going on and we’ll help you find the right oncologist — free, with no obligation.

Chat with our care team on WhatsApp

Not sure who to see? Find the right specialist →

In a medical emergency, or for severe or sudden symptoms such as breathing difficulty, chest pain, fainting or stroke signs, call 995 immediately.

Coming to Singapore from overseas for treatment? See our guide for international patients — costs, visas, travel and language support — or chat with our care team on WhatsApp.

The key idea: a targeted drug only helps if the cancer actually has the target it’s designed to block. That’s why the tumour is often tested first – and why targeted therapy isn’t an option for every cancer.

What targeted therapy is

Targeted therapy is a type of cancer treatment that acts on specific molecules or pathways that cancer cells rely on to grow, survive and spread. Cancers arise because of particular faults – for example a mutated protein or an overactive growth signal – that push their cells to multiply out of control. A targeted drug is designed to block or interfere with one of these faults. Because it is aimed at a feature the cancer particularly depends on, it can be more precise than older treatments.

Unlike traditional chemotherapy, which affects fast-dividing cells across the body fairly broadly, targeted therapy is directed at a particular characteristic of the cancer. That greater precision is a real advantage, but it does not make the treatment side-effect-free, and it does not work for every cancer. It is one tool among several – used on its own or alongside surgery, radiotherapy, chemotherapy or immunotherapy – and your oncology team will explain where it fits in your own plan.

How it differs from chemotherapy

Chemotherapy works broadly: it damages cells that divide quickly, which includes cancer cells but also some healthy fast-growing cells, such as those in hair follicles, the gut lining and the bone marrow (hence effects like hair loss, mouth soreness and low blood counts). Targeted therapy instead homes in on a specific molecular target, so it can spare more normal cells. This does not mean it is gentle or free of side effects – it simply has a different profile, shaped by the target it acts on.

Why testing the tumour matters (precision oncology)

Many targeted therapies only work if the cancer carries a particular change – often called a biomarker or genetic alteration. For this reason the cancer is usually tested first, before treatment is chosen. Doctors carry out biomarker testing (molecular testing) by examining a sample of the tumour – taken at biopsy or surgery – or sometimes a blood sample, looking for specific gene changes or proteins. The result guides whether a particular targeted drug is likely to help.

This “test first, then match the treatment” approach is the heart of precision (personalised) oncology. In Singapore, molecular and biomarker testing is a routine part of cancer care at centres such as the National Cancer Centre Singapore and the National University Cancer Institute, Singapore (NCIS), and your oncologist will arrange the tests relevant to your cancer. Honestly, though, not every cancer has a targetable change, so targeted therapy is not an option for everyone – and a normal test result does not mean your treatment has failed, only that a different approach may suit you better.

Types of targeted therapy in plain terms

Targeted therapies are often grouped by how they are built and where they act. You do not need to learn individual drug names – the descriptions below are general, and your team will tell you which type applies to you and why.

Small-molecule medicines – often taken as tablets, these are small enough to enter cancer cells and block signals inside them. Growth-signal blockers (kinase inhibitors) are a common example: they switch off an overactive “divide and grow” message the cancer relies on;
Antibody-based treatments – larger, laboratory-made proteins (monoclonal antibodies) that recognise a feature on or around cancer cells and flag or block it. HER2-directed drugs, used for some breast and stomach cancers that make too much of a growth protein, are one familiar example;
Blood-supply blockers (anti-angiogenesis drugs) – these cut off the signals a tumour uses to build its own blood vessels, effectively starving it of the nutrients it needs to grow;
Hormone-driven approaches – for cancers fuelled by hormones (such as some breast and prostate cancers), treatments that lower or block those hormones can be thought of as a form of targeted approach.

What it is used for

Targeted therapy is used across a range of cancers where a suitable target is present – among them some breast, lung, bowel, kidney, liver and blood cancers, and others. It may be given on its own or combined with chemotherapy, radiotherapy, immunotherapy or surgery, depending on the type and stage of the cancer and the goals of treatment. What matters is whether your particular cancer carries the target the drug is designed for.

How it is given

Some targeted drugs are tablets or capsules taken at home, often daily; others are given as an infusion (a drip) in a day unit, usually in cycles. Treatment runs over a course guided by your team, with regular reviews to check how you are responding and how you are tolerating it. Because oral targeted therapy is largely managed by you between clinic visits, your team will explain the schedule carefully and give you a point of contact for questions.

Benefits and realistic expectations

Targeted therapy can be effective, and for the right cancer it is sometimes better tolerated than chemotherapy. But it is important to hold hope and realism together. Responses vary from person to person. A drug that works well at first may, over time, stop working as the cancer adapts – this is called resistance: the target itself may change so the drug no longer fits, or the cancer finds another route to grow. Resistance is a common reason a treatment that was helping needs to be switched, and research into overcoming it is very active. Your oncologist can give you a realistic picture for your own situation – what the treatment aims to achieve, and what the alternatives are if it stops working.

Side effects

Side effects differ from drug to drug and are usually different from those of chemotherapy. Depending on the treatment they can include skin and nail changes (rash, dryness, sore or brittle nails), diarrhoea, raised blood pressure, tiredness, mouth sores, changes in liver blood tests, and others. The severe hair loss and large drops in blood counts associated with chemotherapy are less typical, but targeted drugs are not “gentle” and do need monitoring. Most side effects can be managed, especially when caught early, so it is important to report anything new or troublesome to your cancer team rather than waiting for the next scheduled visit.

Taking oral targeted therapy safely

If your treatment is tablets taken at home, taking it exactly as prescribed makes a real difference. Take it at the times your team advises and do not stop or change the dose without speaking to them first, even if you feel unwell – ask what to do if you miss a dose or vomit soon after taking one. Some targeted drugs interact with other medicines, supplements or herbal remedies, and a few interact with certain foods (grapefruit and grapefruit juice affect how some drugs are handled by the body, for example), so tell your team and pharmacist about everything else you take and ask what to avoid. Store the medicine as advised, keep it away from children, and follow any guidance on handling. Building the tablet into a daily routine, and keeping a simple diary of doses and side effects, helps you stay on track and gives your team useful information.

Monitoring during treatment

Because targeted drugs can affect blood pressure, the liver and other organs, treatment includes regular reviews and blood tests. Your team may check your blood pressure, liver and kidney function and other results at intervals, and adjust the dose or pause treatment if needed. Keep your review appointments even when you feel well – monitoring is how problems are caught early and how your team confirms the treatment is still the right one for you.

Living through treatment and support

Cancer treatment affects more than the body. Fatigue, worry and the practical demands of appointments and medicines are common, and support is available. In Singapore, organisations such as the Singapore Cancer Society and the cancer centres’ own support and counselling services offer help with the emotional and practical side of treatment, and HealthHub provides reliable local health information. Your oncology team, specialist nurses and pharmacists are there for day-to-day questions, and letting them know how you are coping – not just your physical symptoms – is part of good care.

When to seek help and red flags

Contact your cancer team promptly for any troublesome or new side effect – a severe skin rash, persistent diarrhoea, high blood-pressure readings, unusual tiredness, mouth sores, breathlessness or swelling, yellowing of the skin or eyes (a possible sign of a liver problem), or simply feeling very unwell. Do not stop your medicine on your own; ask your team what to do.

Seek urgent or emergency care (go to A&E or call 995) for severe breathlessness, chest pain, severe diarrhoea or signs of dehydration, or a high fever with feeling very unwell – which during cancer treatment can signal a serious infection that needs immediate attention. A cancer specialist supervises your treatment and can advise on anything that worries you.

Related cancer & treatment topics

Sources

Macmillan Cancer Support — Targeted therapies: what it is, biomarker testing, target types (angiogenesis/growth inhibitors, monoclonal antibodies).
National Cancer Institute (US) — how targeted therapy differs from chemo; kinase and angiogenesis inhibitors; resistance; side effects.
Cancer Research UK — Targeted cancer drugs: how they work and how they’re given.
National Cancer Centre Singapore — targeted, immuno- and chemotherapy offered for solid tumours (SG context).

General information only. This guide is general information about cancer or its treatment and is not a diagnosis or personalised medical advice. Decisions about diagnosis and treatment should be made with your own doctors — a GP and a cancer specialist (oncologist). If you are having cancer treatment and develop a fever, chills or feel suddenly unwell, contact your cancer team or go to A&E straight away — this can be a sign of a serious infection (neutropenic sepsis) that needs urgent care.

Targeted Therapy for Cancer in Singapore: A Patient Guide