Interventional Oncology in Türkiye: Minimally Invasive Treatments for Cancer

Modern interventional oncology, a specialised field within interventional radiology, allows selected cancers and metastases to be treated directly using image-guided needles, probes and microcatheters.

Depending on the cancer and stage of disease, these treatments may be used to destroy a tumour, control local disease, deliver chemotherapy or radiation directly to the tumour, relieve symptoms, or form part of a wider multidisciplinary cancer treatment strategy.

Türkiye has developed substantial capabilities in advanced interventional radiology, with experienced specialists working within multidisciplinary cancer centres alongside medical oncology, surgical oncology, radiation oncology, nuclear medicine and organ-specific surgical teams.

For international patients, however, access to an advanced procedure should never be the starting point.

The diagnosis, pathology, stage, previous treatments and original imaging should first be reviewed to determine whether interventional treatment is appropriate — and, if so, which technique belongs within the overall cancer treatment plan.

WHAT IS INTERVENTIONAL ONCOLOGY?

Interventional oncology uses imaging such as ultrasound, CT, MRI, fluoroscopy, angiography and cone-beam CT to reach and treat tumours with high anatomical precision.

There are two principal approaches.

PERCUTANEOUS TUMOUR ABLATION

A needle or probe is positioned directly within or around the tumour under imaging guidance. The targeted tissue can then be destroyed using heat, cold or electrical energy.

Principal techniques include:

• Microwave Ablation (MWA)
• Radiofrequency Ablation (RFA)
• Cryoablation
• Irreversible Electroporation (IRE)

Newer non-invasive technologies such as histotripsy are also emerging internationally.

TRANSARTERIAL CANCER TREATMENT

Some cancers — particularly liver tumours — can instead be approached through the arteries supplying them.

An interventional radiologist introduces a small catheter, usually through an artery in the wrist or groin, and navigates microcatheters selectively into the vessels feeding the tumour.

Major techniques include:

• Transarterial Embolization (TAE)
• Transarterial Chemoembolization (TACE)
• Drug-Eluting Bead TACE (DEB-TACE)
• Transarterial Radioembolization (TARE)
• Yttrium-90 (Y-90) Radioembolization
• Radiation Segmentectomy

These treatments are not interchangeable. The appropriate technique depends on the cancer type, pathology, stage, tumour size, number and location of lesions, organ function, previous treatments and overall treatment objective.

LIVER CANCER AND LIVER METASTASES

The liver is one of the most developed areas of modern interventional oncology.

Image-guided and transarterial treatments may be considered in selected patients with:

• Hepatocellular carcinoma (HCC)
• Intrahepatic cholangiocarcinoma
• Colorectal cancer liver metastases
• Neuroendocrine tumour liver metastases
• Selected liver metastases from other cancers

A crucial distinction is that a liver lesion is not itself a diagnosis.

A hepatocellular carcinoma, colorectal liver metastasis and neuroendocrine liver metastasis have different tumour biology and may require completely different treatment strategies.

MICROWAVE ABLATION (MWA)

Microwave ablation uses electromagnetic energy to rapidly heat and destroy targeted tumour tissue.

Under ultrasound or CT guidance, an ablation probe is positioned within the lesion and a controlled treatment zone is created around the tumour.

MWA is particularly relevant for selected:

• primary liver cancers
• colorectal liver metastases
• other limited liver metastases
• kidney tumours
• lung tumours
• bone lesions

In appropriately selected small liver tumours, thermal ablation may form part of a potentially curative treatment strategy.

RADIOFREQUENCY ABLATION (RFA)

Radiofrequency ablation also destroys tumour tissue through controlled heating.

An electrode is positioned within the tumour under image guidance and radiofrequency energy produces thermal destruction of the targeted tissue.

RFA has established applications in selected:

• hepatocellular carcinomas
• liver metastases
• kidney tumours
• lung lesions
• bone tumours and metastases

Whether RFA, MWA, surgery or another treatment is preferable depends on factors including tumour size, location, treatment margins, proximity to blood vessels or other critical structures, organ function and overall oncological strategy.

TACE — TRANSARTERIAL CHEMOEMBOLIZATION

Transarterial chemoembolization (TACE) combines targeted delivery of chemotherapy with embolization of the tumour’s arterial blood supply.

A microcatheter is advanced selectively into the arteries feeding the tumour. Chemotherapy and embolic material are then delivered directly into the tumour circulation.

TACE has an established role particularly in selected patients with hepatocellular carcinoma.

Modern techniques allow treatment to be performed selectively or superselectively, targeting individual tumour-feeding vessels while preserving as much healthy liver tissue as possible.

DEB-TACE — DRUG-ELUTING BEAD CHEMOEMBOLIZATION

Drug-Eluting Bead TACE (DEB-TACE) uses microspheres that both embolize the tumour’s arterial supply and release chemotherapy locally.

Whether conventional TACE or DEB-TACE is appropriate depends on the individual tumour and clinical situation.

TAE — TRANSARTERIAL EMBOLIZATION

Transarterial embolization (TAE) blocks the arterial blood supply to a tumour without adding chemotherapy.

It can be relevant particularly for selected hypervascular tumours and liver-dominant metastatic disease, including certain neuroendocrine tumour liver metastases.

TARE / Y-90 RADIOEMBOLIZATION

Transarterial radioembolization (TARE) delivers radiation directly into tumour-bearing liver tissue through its arterial circulation.

Microscopic radioactive particles — most commonly containing Yttrium-90 (Y-90) — are delivered selectively through the hepatic arteries supplying the tumour.

Y-90 radioembolization may be considered in selected patients with:

• Hepatocellular carcinoma
• Intrahepatic cholangiocarcinoma
• Colorectal liver metastases
• Neuroendocrine liver metastases
• Other selected liver-dominant metastatic cancers

Modern radioembolization increasingly uses personalised dosimetry and highly selective treatment planning to optimise the radiation dose delivered to tumour tissue while limiting unnecessary exposure to healthy liver.

RADIATION SEGMENTECTOMY

Radiation segmentectomy is a highly selective form of Y-90 radioembolization.

Instead of treating a large portion of the liver, radioactive microspheres are delivered into the small arterial territory containing the tumour.

This allows an ablative radiation dose to be concentrated within a defined tumour-bearing segment while preserving uninvolved liver.

For appropriately selected localised liver cancers, radiation segmentectomy may form part of a definitive local treatment strategy.

COLORECTAL CANCER LIVER METASTASES

Colorectal cancer commonly spreads to the liver.

Surgical resection remains a major potentially curative treatment when liver metastases are resectable. However, selected patients may also benefit from image-guided local treatment.

Options can include:

• Microwave ablation
• Radiofrequency ablation
• Selected Y-90 radioembolization strategies
• Combined surgery and ablation
• Local treatment integrated with systemic therapy

This may be particularly relevant in carefully selected patients with limited or oligometastatic disease.

The key question is not simply whether an individual metastasis can technically be ablated, but whether local treatment contributes meaningfully to control of the patient’s overall cancer.

NEUROENDOCRINE TUMOUR LIVER METASTASES

Neuroendocrine tumours can produce highly vascular liver metastases.

Depending on tumour biology, disease distribution, symptoms and previous treatment, liver-directed options may include:

• Thermal ablation
• TAE
• TACE
• Y-90 radioembolization

These treatments may be integrated with systemic and nuclear medicine therapies rather than considered in isolation.

CRYOABLATION — FREEZING THE TUMOUR

Cryoablation destroys cancer cells through controlled cycles of freezing and thawing.

During treatment, the resulting ice ball can be visualised on imaging, allowing the treatment zone to be monitored in relation to surrounding structures.

Cryoablation may be used for selected:

• Kidney cancers
• Lung tumours
• Bone tumours and metastases
• Soft-tissue tumours
• Selected liver lesions

It can also play an important role in treating selected painful bone metastases.

IRREVERSIBLE ELECTROPORATION (IRE)

Irreversible electroporation is a predominantly non-thermal ablative technique.

Precisely delivered high-voltage electrical pulses create permanent microscopic pores in tumour-cell membranes, leading to cell death.

Because it does not rely primarily on heating or freezing tissue, IRE has attracted particular interest for selected tumours where proximity to important anatomical structures may make conventional thermal ablation difficult.

It has been investigated in selected:

• Liver tumours
• Pancreatic cancers
• Prostate cancers

However, evidence and guideline recommendations differ considerably between cancer types.

IRE should therefore only be considered following cancer-specific multidisciplinary assessment.

KIDNEY CANCER

For appropriately selected small renal tumours, image-guided ablation can provide a kidney-preserving local treatment option.

Techniques include:

• Cryoablation
• Microwave ablation
• Radiofrequency ablation

Surgery — particularly partial nephrectomy — remains an important standard treatment for localised renal cancer.

Ablation is therefore not automatically preferable simply because it is less invasive.

The decision depends on factors including tumour size and location, kidney function, age, comorbidities and surgical suitability.

Appropriate histological confirmation of the renal mass should also be obtained before ablation.

LUNG CANCER AND PULMONARY METASTASES

Selected primary lung tumours and pulmonary metastases can also be treated percutaneously.

Techniques include:

• Microwave ablation
• Radiofrequency ablation
• Cryoablation

Potential candidates may include selected patients with:

• early-stage primary lung cancer who cannot undergo surgery
• limited pulmonary metastatic disease
• recurrent pulmonary lesions
• selected oligometastatic disease

Tumour size, number and location, proximity to central airways and major vessels, pulmonary reserve and the presence of disease elsewhere must all be considered.

BONE TUMOURS AND BONE METASTASES

Interventional oncology can have an important role in both local tumour treatment and symptom control in selected patients with malignant bone disease.

Tumour-directed techniques may include:

• Radiofrequency ablation
• Microwave ablation
• Cryoablation

When cancer has weakened the bone, ablation can sometimes be combined with image-guided stabilisation procedures such as:

• Cementoplasty
• Vertebroplasty
• Kyphoplasty

Depending on the clinical objective, treatment may aim to achieve pain control, local tumour control, mechanical stabilisation or reduction of fracture-related morbidity.

Management may require collaboration between interventional radiology, radiation oncology, orthopaedic oncology and medical oncology.

THYROID CANCER

Image-guided thermal ablation also has an evolving role in selected thyroid cancers.

Radiofrequency ablation (RFA) and other thermal techniques may be considered in specialised settings for carefully selected:

• Low-risk papillary thyroid microcarcinomas
• Locally recurrent thyroid cancer
• Selected metastatic cervical lymph nodes

This does not mean that ablation has replaced thyroid surgery or active surveillance.

Pathology, tumour subtype and size, anatomical location, extrathyroidal extension, lymph-node involvement and overall oncological risk must first be assessed.

PROSTATE CANCER AND FOCAL THERAPY

Focal therapy aims to destroy the clinically significant prostate cancer while preserving as much uninvolved prostate tissue as possible.

Techniques include:

• High-Intensity Focused Ultrasound (HIFU)
• Cryotherapy / Cryoablation
• Irreversible Electroporation (IRE)
• Other emerging focal ablative technologies

The objective is to achieve local cancer control while potentially reducing treatment-related effects on urinary and sexual function.

However, focal prostate therapy remains an evolving area and is not a universal alternative to radical prostatectomy or radiotherapy.

Appropriate selection requires assessment of:

• PSA
• Multiparametric prostate MRI
• Prostate biopsy and histopathology
• Gleason score / ISUP Grade Group
• Tumour location and extent
• Overall prostate cancer risk classification

PANCREATIC CANCER AND IRE

Irreversible electroporation (IRE) has been investigated in selected patients with pancreatic cancer, particularly locally advanced disease.

Its predominantly non-thermal mechanism has generated interest because pancreatic tumours can lie close to major vascular and other critical structures.

However, pancreatic cancer treatment remains fundamentally multidisciplinary.

IRE is not a replacement for established surgical, systemic or radiation treatment pathways and should only be considered for highly selected patients following specialist assessment.

HISTOTRIPSY — AN EMERGING NON-INVASIVE ABLATION TECHNOLOGY

Histotripsy is one of the newest developments in image-guided tumour treatment.

Unlike RFA or microwave ablation, it does not destroy the tumour through heat.

Unlike cryoablation, it does not freeze it.

Instead, focused high-amplitude ultrasound pulses create controlled cavitation that mechanically disrupts targeted tumour tissue without inserting an ablation probe into the tumour.

Clinical use has begun internationally, particularly for selected primary and metastatic liver tumours, while research into long-term oncological outcomes and additional applications continues.

Histotripsy should currently be regarded as an emerging technology with less mature long-term evidence than established treatments such as thermal ablation, TACE and radioembolization.

WHICH INTERVENTIONAL CANCER TREATMENT IS APPROPRIATE?

There is no single “best” interventional oncology procedure.

A small hepatocellular carcinoma is not the same clinical problem as multiple colorectal liver metastases.

A small renal tumour is different from metastatic renal cancer.

A solitary pulmonary metastasis is different from widespread metastatic disease.

And a tumour that is technically accessible is not automatically a tumour that should be ablated.

Treatment selection may depend on:

• Cancer type and histopathology
• Molecular characteristics where relevant
• Disease stage
• Tumour size
• Number of lesions
• Exact anatomical location
• Presence of metastatic disease elsewhere
• Liver, kidney and other organ function
• Previous surgery
• Previous chemotherapy, immunotherapy or targeted therapy
• Previous radiotherapy
• Performance status and general medical condition
• Alternative surgical, systemic and radiation treatments

WHY MULTIDISCIPLINARY ASSESSMENT MATTERS

Interventional oncology should not be approached as a catalogue of procedures.

Sometimes surgery offers the best chance of cure.

Sometimes ablation provides an effective local treatment without major surgery.

Sometimes systemic therapy needs to come first.

Sometimes radiotherapy is more appropriate.

And increasingly, selected patients may benefit from a carefully planned combination of surgery, systemic therapy, radiotherapy, nuclear medicine and interventional oncology.

The technology should follow the cancer treatment strategy — not determine it.

WHAT SHOULD BE REVIEWED BEFORE TRAVELLING FOR TREATMENT?

For an international patient considering interventional cancer treatment in Türkiye, medical assessment should ideally begin before travel is planned.

Depending on the diagnosis, review may include:

• Pathology and biopsy reports
• Pathology slides or blocks when additional review is required
• Original CT images
• Original MRI images
• PET/CT when relevant
• Previous surgical reports
• Chemotherapy, immunotherapy and targeted therapy records
• Previous radiotherapy records
• Tumour markers
• Molecular or genetic tumour results where relevant
• Current blood results
• Current medications
• Previous multidisciplinary recommendations

Whenever possible, original DICOM imaging should be reviewed rather than relying only on written radiology reports.

For interventional treatment planning, the exact tumour dimensions, location, vascular anatomy, relationship to surrounding structures and achievable treatment margins can be crucial.

INTERVENTIONAL ONCOLOGY IN TÜRKİYE

Türkiye has developed substantial capabilities in contemporary image-guided cancer treatment, including thermal ablation, cryoablation, embolization, chemoembolization and radioembolization, supported by multidisciplinary medical, surgical, radiation and nuclear medicine oncology services.

For an international patient, however, the important question is not simply:

“Is this treatment available in Türkiye?”

The more important question is:

“Is this the correct treatment for my cancer?”

Healing Journey therefore approaches these cases through medical review and treatment-pathway assessment first.

The patient’s diagnosis, pathology, original imaging, stage, previous treatments and current clinical condition are reviewed to determine the appropriate medical expertise and provider capabilities required for the individual case.

Where interventional oncology is appropriate, treatment can then be coordinated within the wider cancer treatment plan, including collaboration with medical oncology, surgical oncology, radiation oncology, nuclear medicine and relevant organ-specific specialists.

The objective is not simply to identify the newest or least invasive procedure.

It is to determine the treatment — or combination of treatments — that is medically appropriate for the individual cancer and the individual patient.

Medical note: Interventional oncology indications vary substantially according to cancer type, pathology, disease stage, tumour anatomy, organ function, previous treatment and individual patient factors. Suitability for ablation, embolization, radioembolization or other image-guided cancer treatments can only be determined after individual medical assessment.