This fact is from Head Neck Cancer TNM in General Surgery. It is a commonly tested concept in NEET MDS examinations. Understanding this fact is crucial for answering MCQs correctly.
T1 = tumor less than 2cm
T3 = tumor greater than 4cm
T4 = invasion of adjacent structures bone skin
N0 = no regional lymph node metastasis
N1 = single ipsilateral node less than 3cm
Radical neck dissection = removes all 5 structures SCM IJV SAN
Modified radical = spares 1 or more structures
Selective neck dissection = specific levels only.