Background: Sentinel lymph node biopsy (SLNB) has emerged as the standard axillary staging procedure in early-stage breast cancer, replacing routine axillary lymph node dissection (ALND) in clinically node-negative patients. This prospective observational study evaluated the pathological findings of SLNB and its surgical implications in a tertiary-care oncosurgery setting in South India. Methods: Eighty female patients with histologically confirmed early-stage breast cancer (T1–T2, cN0) were enrolled between March 2021 and January 2022. SLNB was performed using a dual-technique approach with technetium-99m radiocolloid and patent blue dye. Intraoperative frozen section analysis and postoperative paraffin-embedded histopathology with immunohistochemistry were performed. Patients with positive SLNs underwent completion ALND. Outcomes including morbidity, lymphoedema rates, and patient satisfaction were compared between SLNB-alone and SLNB+ALND groups. Results: The sentinel node identification rate was 95% (76/80). Of these, 31.6% (24/76) had SLN metastasis, with macrometastasis in 58.3% and micrometastasis in 41.7% of positive cases. Tumour size, histological grade, and lymphovascular invasion showed statistically significant associations with SLN positivity (p<0.05). The SLNB-alone group demonstrated significantly lower rates of lymphoedema (2.6% vs 28.6%), seroma (5.3% vs 32.1%), operative time (68.4 vs 102.6 min), and higher patient satisfaction scores compared to the ALND group. Conclusion: SLNB is a safe, accurate, and minimally morbid axillary staging technique in early-stage breast cancer. Its pathological results directly guide further surgical management, with significant benefits in terms of reduced morbidity and improved quality of life when compared to routine ALND. Integration of dual-technique SLNB into routine surgical practice at regional cancer centres in India is strongly recommended.