Solitary pulmonary nodule — risk stratification and management SAQ

Definition and triage. This is a solitary pulmonary nodule (SPN) — a single, well-defined, roughly spherical opacity 3 cm or less in greatest diameter (here 14 mm), surrounded by aerated lung, with no associated atelectasis, adenopathy, or pleural effusion. It is NOT a mass (a mass is over 3 cm and presumed malignant). There is no acute complication (no haemoptysis, post-obstructive pneumonia, or SVC obstruction), so the patient enters the risk-stratified outpatient pathway rather than an urgent inpatient one.^[1][5]

Characterise on thin-section CT — the high-risk features. Several features raise the malignant probability: spiculated border (the classic 'sunburst' sign of uneven malignant growth), upper-lobe location (lung cancer is upper-lobe predominant), solid density with no benign calcification pattern and no fat (no hamartoma or healed-granuloma features), and the absence of any prior imaging to apply the 2-year stability rule. None of the four benign calcification patterns (central, laminated/'target', diffuse, 'popcorn') is present, so the work-up cannot be ended on imaging grounds alone.^[1]

Quantify risk with validated models (the BTS 2015 chain).

1. Brock (PanCan) model first — variables include sex, age, family history of lung cancer, emphysema, nodule size, nodule type (part-solid highest), upper-lobe location, nodule count, and spiculation. In this patient (older, smoker, 14 mm solid, spiculated, upper lobe) the Brock probability would be expected to exceed 10 percent, triggering the second step.^[2]
2. Herder model (Brock + PET) — adds FDG-PET uptake (none/faint/intense). The intense uptake (SUV max 5.8) raises the probability into the high band (here ~78 percent).^[3]
3. BTS thresholds: Herder over 70 percent → offer treatment; 10-70 percent → PET-CT/biopsy with MDT; under 10 percent → CT surveillance. This patient is in the over 70 percent band.^[2][3]

Definitive management — resect, do not biopsy. Because the pre-test probability of cancer is high (over 65-85 percent) and the patient is fit for surgery, the correct management is to proceed straight to surgical resection — a video-assisted thoracoscopic (VATS) wedge resection with intra-operative frozen section, proceeding to anatomic lobectomy with mediastinal lymph node sampling/dissection if malignant. A pre-operative needle biopsy adds nothing (the nodule will be excised regardless), risks seeding the needle track, and may cause a pneumothorax that complicates surgery. Biopsy is reserved for the intermediate-probability nodule whose result will change management.^[5]

If medically inoperable. For a high-risk nodule in a patient unfit for surgery, the alternative is SBRT (stereotactic body radiotherapy), which delivers a biologically potent dose in a few fractions with local control over 90 percent.

Safety-net and disposition. Refer to the lung-cancer multidisciplinary team (MDT); stage with the staging CT-PET already obtained; ensure a named responsible clinician and a clear plan; and counsel the patient that a resected stage IA lung cancer has a 5-year survival of over 80-90 percent, which is the whole rationale for not delaying.