Head and Neck Radiotherapy Side Effects and Management: Early and Late Complications

Radiotherapy in head and neck cancer is used alone, adjuvantly after surgery, or combined with chemotherapy (chemoradiotherapy — CRT). Goal: tumor cell destruction via DNA damage.

Standard treatment: 60-70 Gy total in 30-35 fractions (5 days/week, 6-7 weeks). Modern techniques: intensity-modulated radiotherapy (IMRT — spares healthy tissue), image-guided RT (IGRT — daily position verification), stereotactic body RT (SBRT — selected indications).

Side effects are more severe with conventional (2D, 3D-CRT) techniques than with IMRT/IGRT. Modern technique mitigates but does not eliminate all side effects.

Side effects fall into two categories: early (acute — during treatment and the first 3 months) and late (chronic — beyond 3 months, even years). Early effects involve mucosal structures; late effects connective tissue, bone and vessels.

Severity depends on dose, treatment field, concurrent chemotherapy (cisplatin, cetuximab), age, nutritional status, smoking/alcohol, dental health. Related service: our head and neck cancer surgery programme.

Oral mucositis: the most common and distressing early effect. Begins in week 2, peaks at weeks 4-5, resolves 2-4 weeks after treatment. Burning, pain, ulcers, bleeding, eating difficulty. Management: cold saline rinses (4-6×/day), viscous lidocaine, sucralfate suspension, palifermin (mucositis prophylaxis), morphine rinses (severe), systemic analgesics (paracetamol → opioids). Diet: soft, lukewarm, no spice, no acid. PEG tube if poor intake or 10% weight loss.

Dysphagia: from mucositis + oedema + fibrosis. Even liquids may be difficult; small frequent meals, smoothies/shakes, PEG feeding if needed. Swallowing exercises (SLP — speech language pathologist) start during treatment.

Dysgeusia (taste change): taste receptors are radiation-sensitive. Foods taste "metallic" or "bland". Partial recovery in 3-6 months; complete may take up to 1 year.

Acute skin reaction (radiodermatitis): erythema → dry desquamation → moist desquamation → ulceration. Management: gentle cleansing (soap-free or very mild), moisturisers (Aquaphor, calendula, hyaluronic acid cream), sun protection, avoid friction, steroid-free creams (steroids contraindicated in moist desquamation), silver sulfadiazine or hydrogel dressings for moist desquamation.

Xerostomia onset: starts week 2-3 — pronounced when salivary glands (parotid, submandibular) are near target. Frequent sips of water, xylitol gum, artificial saliva spray, oral moisturising.

Laryngeal oedema and hoarseness: if glottis or hypopharynx is in the field. Acute hoarseness; rarely acute stridor (urgent management). Steam inhalation, dexamethasone, voice rest.

Fatigue: in nearly all patients. Cumulative; gradually improves 1-3 months after treatment. Manage with regular light exercise, adequate sleep, treating anaemia.

Nausea-vomiting: when the field is near the middle ear or midbrain. Antiemetics (ondansetron, metoclopramide).

Persistent xerostomia: the most common late effect. Even with IMRT, 40-60% have long-term dryness. Complications: caries (lost salivary buffer), chewing/swallowing difficulty, oral infections (often Candida), taste change. Management: daily fluoride gel (custom tray), artificial saliva spray/gel, xylitol gum, pilocarpine (cholinergic — increases saliva), frequent sips of water, oral moisturisers (Biotene, OralBalance).

Caries and tooth loss: from xerostomia + RT-related dental changes. Strict hygiene + daily fluoride + dental follow-up every 3-6 months are essential. Post-RT extraction raises osteoradionecrosis risk — extractions should be done before RT.

Osteoradionecrosis (ORN): mandible most affected. Mechanism: hypoxic, hypovascular, hypocellular bone. Clinical: exposed bone (>3 months), pain, fistula, infection. Treatment: conservative (local care, antibiotics) + hyperbaric oxygen (HBO — 30-40 sessions) + surgical resection and reconstruction (free fibula flap in advanced cases). Prevention: pre-RT dental care, avoid post-RT extraction.

Lymphoedema: after neck dissection or RT, lymphatic drainage is impaired. Face, jaw and neck swelling. Treatment: manual lymphatic drainage by specialist physiotherapist, compression, exercise, skin care.

Fibrosis and trismus: skin, subcutaneous tissue and muscles of mastication (masseter, medial pterygoid) fibrose. Mouth opening becomes limited (trismus — interincisal opening <35 mm). Treatment: mouth-opening exercises (Therabite, finger exercises), physiotherapy, surgery if needed.

Hypothyroidism: when the neck RT field includes the thyroid, hypothyroidism develops in 20-40% (1-5 years after treatment). Annual TSH monitoring is standard. Levothyroxine replacement.

Vascular disease: carotid intima-media thickening and atherosclerosis accelerate. Carotid stenosis and stroke risk rises over 5-10 years. Annual carotid Doppler, risk factor modification, carotid endarterectomy if indicated.

Hypopituitarism: if pituitary is near the field, function may decline. Nonspecific symptoms (fatigue, weight, libido). Endocrinology follow-up.

Secondary cancers: 10-20-year risk of new cancers in the field (especially in smokers). Regular follow-up + smoking cessation support.

Neurocognitive change: memory and attention deficits in brain RT fields. Neurocognitive rehabilitation.

Permanent voice and swallowing problems: especially after laryngeal/pharyngeal surgery + RT. Long-term SLP rehabilitation. More detail: multidisciplinary tumour board.

A comprehensive dental evaluation at least 2-3 weeks before RT begins. Goal: prevent post-RT extraction (osteoradionecrosis risk).

Dental work done: extraction of advanced carious teeth (allow 2-3 weeks healing before RT), restoration (fillings), periodontal care, oral hygiene education, fluoride tray (custom appliance for daily fluoride gel) preparation.

Teeth requiring extraction: poor periodontal status, advanced periodontal disease, unrestorable caries, symptomatic impacted teeth (when indicated). Preserve as much as possible; healing time affects RT planning.

Nutritional assessment: weight, BMI, weight loss over 3 months, hypoalbuminaemia, comorbidities. >10% weight loss during treatment is highly impactful. PEG tube may be placed prophylactically or reactively — especially when severe mucositis is expected (oropharynx/hypopharynx).

Smoking and alcohol cessation: reduce RT efficacy and worsen side effects. Quitting during treatment and long-term improves survival. Nicotine replacement + counselling + medications recommended.

Other preparation: eyewear if needed (mask fitting), hair trimming (depending on field), personal hygiene.

A multidisciplinary team is the gold standard. Core members: ENT surgeon, radiation oncologist, medical oncologist, dentist, dietitian, SLP (speech-language pathologist), physiotherapist, psychologist, social worker, pain specialist.

Post-treatment follow-up protocol: every 1-3 months in the first 2 years, every 3-6 months years 3-5, yearly thereafter. Each visit: physical exam, nasopharyngoscopy/laryngoscopy, imaging when indicated (MRI/CT), bloods (TSH, CBC, biochemistry), dental care.

Early recurrence detection: new cervical lymph node, changing hoarseness, bloody sputum, pain, weight loss, dyspnoea. Biopsy if suspicious.

Lymphoedema management: certified lymphoedema physiotherapist. Manual lymphatic drainage (2-3 times weekly, then home program), compression garments.

Swallowing rehabilitation: weekly SLP sessions. Mendelsohn manoeuvre, supraglottic swallow, effort swallow techniques. Severe dysphagia: permanent PEG or swallowing-space surgery.

Voice rehabilitation: tracheoesophageal puncture (TEP), oesophageal speech, electrolarynx after total laryngectomy. Voice therapy after partial laryngectomy.

Psychosocial support: depression and anxiety are frequent (especially with facial change, voice loss, swallowing problems). Psychotherapy + SSRI when needed. Support groups help.

Pain management: chronic neuropathic pain (especially after neck dissection + RT) — gabapentin, pregabalin. Trigeminal-like — carbamazepine. Chronic mucositis/ulcer pain — opioid, local anaesthetic.

Long-term smoking cessation support: critical for preventing recurrence and second primaries. Related reading: our multidisciplinary tumour board.