A 52-year-old man presents with a 3-month history of a painless, slow-growing swelling in the right parotid region. On examination, there is a 2 cm firm, mobile mass in the superficial lobe of the parotid gland. Facial nerve function is intact. There are no skin changes or signs of malignancy. What is the most appropriate next step in management?

Explanation

## Clinical Presentation Analysis The patient presents with a **painless, slow-growing, mobile parotid mass** with **intact facial nerve function** — classic features of a **benign parotid tumor** (most likely pleomorphic adenoma). ## Diagnostic Algorithm for Parotid Masses **Key Point:** FNAC is the **first-line investigation** for parotid masses because it is: - Non-invasive - Cost-effective - Highly accurate (85–95% sensitivity for benign vs. malignant differentiation) - Does not risk tumor seeding or facial nerve injury - Can be performed in outpatient setting **High-Yield:** The diagnostic sequence for parotid tumors is: 1. **Clinical examination** (size, mobility, nerve involvement, skin changes) 2. **FNAC** (cytology to stratify benign vs. malignant) 3. **Imaging** (ultrasound ± MRI) — reserved for: - Inconclusive FNAC results - Suspected malignancy (to assess deep lobe, mandibular involvement, skull base) - Pre-operative planning in complex cases 4. **Surgery** (parotidectomy) — indicated after FNAC confirms diagnosis ## Why FNAC First? **Clinical Pearl:** In this case: - Mass is **small (2 cm)**, **mobile**, **painless** → low suspicion for malignancy - **Facial nerve intact** → no nerve involvement - FNAC will confirm benign histology (likely pleomorphic adenoma) and guide surgical planning - MRI is **not first-line** — it adds cost and delay without changing immediate management **Mnemonic:** **FNAC FIRST** for parotid masses: - **F**ine needle (non-invasive) - **N**on-traumatic - **A**ccurate cytology - **C**ost-effective - **F**acial nerve safe (no risk of seeding/injury) - **I**maging reserved for inconclusive results - **R**eliable for benign/malignant stratification - **S**urgery planned after diagnosis - **T**ime-efficient ## Management Pathway ```mermaid flowchart TD A[Parotid mass on exam]:::outcome --> B{Clinical features?}:::decision B -->|Benign features:<br/>Mobile, painless,<br/>nerve intact| C[FNAC]:::action B -->|Malignant features:<br/>Fixed, pain,<br/>nerve involved| D[MRI + FNAC]:::action C --> E{FNAC result?}:::decision E -->|Benign<br/>pleomorphic adenoma| F[Superficial parotidectomy]:::action E -->|Inconclusive| G[MRI for staging]:::action E -->|Malignant| H[MRI + staging,<br/>then radical surgery]:::action D --> I[Radical parotidectomy<br/>± neck dissection]:::action ```