When is radiotherapy a viable treatment option for cancer?

When Radiotherapy is a Viable Treatment Option for Cancer

Radiotherapy is a viable treatment option in three primary scenarios: as definitive curative treatment when surgery is contraindicated or refused, as adjuvant therapy after surgery to reduce local recurrence, and as palliative treatment for symptom control in advanced disease. 1

Curative Intent Radiotherapy (Primary Treatment)

As Alternative to Surgery

• Early-stage lung cancer (Stage I-II): Curative external-beam radiotherapy with classical fractionation is an alternative to surgical excision only in patients with medical contraindications for surgery or those who refuse surgery, delivering >60 Gy to the tumor mass 1
• Cervical cancer (Stage IB-IIA, <4 cm): Radiotherapy combined with brachytherapy is a standard option equivalent to surgery, with the entire treatment course completed in <8 weeks 1
• Esophageal cancer (T1-T2): Combined chemoradiotherapy is an option in certain institutions for patients unfit for surgery or who refuse surgery, though surgical excision remains the recommended standard 1, 2

As Primary Definitive Treatment

• Locally advanced cervical cancer (≥4 cm or Stage IIB-IVA): Concurrent chemoradiotherapy with cisplatin is the standard treatment, showing significant improvement in local control (level of evidence A) and overall survival (level of evidence B) compared to radiotherapy alone 1, 3
• Locally advanced lung cancer (Stage IIIB): Induction chemotherapy containing cisplatin plus conventional radiotherapy is standard, with minimum dose of 60 Gy with classical fractionation 1
• Inoperable esophageal cancer: Combination chemoradiotherapy is the standard treatment when chemotherapy is not contraindicated 1

Adjuvant Radiotherapy (Post-Surgical)

Mandatory Indications

• Breast cancer after lumpectomy: Must be systematically performed for infiltrating carcinoma regardless of disease characteristics, as it decreases local recurrence and specific mortality 4
• Breast cancer after mastectomy: Required for pT3-T4 tumors and any axillary nodal involvement, regardless of number of involved lymph nodes 4
• Soft tissue sarcoma with margins ≤1.0 cm: Randomized clinical trial data support radiotherapy (category 1) based on improvement in disease-free survival 1

Contraindicated Scenarios

• Early-stage lung cancer (Stage I-II N0-N1) after complete excision: Radiotherapy is NOT indicated if excision was complete (standard, level of evidence A) 1

Multimodality Treatment Approaches

Neoadjuvant Radiotherapy

• Rectal cancer (T4 nonmetastatic disease): Preoperative radiation therapy with concurrent 5-FU-based chemotherapy, delivering 45-50 Gy in 25-28 fractions 1
• Soft tissue sarcoma (potentially resectable with functional concerns): Preoperative chemoradiation or chemotherapy is an option 1
• Adenocarcinoma of esophagus/gastroesophageal junction: Preoperative chemoradiation therapy is efficacious (level of evidence B) and constitutes a therapeutic option 1

Trimodality Therapy

• Malignant pleural mesothelioma: Chemotherapy, surgery (extrapleural pneumonectomy), and hemithoracic radiotherapy in selected patients with good performance status, with median survival up to 29 months reported 1

Palliative Radiotherapy

Symptom Control Indications

• Bone or brain metastases: For relief of pain or neurological symptoms 1
• Chest pain from mesothelioma: Palliative doses based on treatment purpose 1
• Esophageal cancer with dysphagia: Small doses per fraction with or without chemotherapy for reasonable performance status patients 1
• Prevention of instrument-tract recurrence: After pleural intervention in mesothelioma 1

Technical Requirements for Viability

Patient Selection Criteria

• Good performance status required for curative intent treatment 1
• Adequate organ function: Particularly pulmonary and kidney function for thoracic radiotherapy 1
• Life expectancy considerations: Hypofractionated or split-course radiotherapy for patients with reduced life expectancy 1

Dose and Fractionation Standards

• Curative doses: Minimum 60 Gy with classical fractionation for lung and esophageal cancers 1
• Cervical cancer: 45-50 Gy external beam plus brachytherapy boost to 60 Gy lateral-pelvic 1
• Hypofractionation: Equivalent to conventional irradiation in selected breast cancer patients (42.5 Gy in 16 fractions, 41.6 Gy in 13, or 40 Gy in 15) 4

Critical Pitfalls to Avoid

• Prolonged treatment duration: Total radiation treatment time (external beam plus brachytherapy) must not exceed 8 weeks for cervical cancer, as prolonged duration negatively impacts local control 1, 3
• Inadequate dose: Delivering <60 Gy for curative intent in lung or esophageal cancer compromises local control 1
• Wrong patient selection: Offering radiotherapy when complete surgical excision with negative margins is feasible and appropriate (e.g., early-stage lung cancer in operable patients) 1
• Ignoring contraindications: Combining radiotherapy with chemotherapy when chemotherapy is contraindicated, rather than using radiotherapy alone 1