Clinical and Quality Efficiency of Fractionated Nanocolloid Kits in Pre-Operative Visualization of Sentinel Lymph Nodes: A Cost-Effective Strategy for Public Sector Hospitals

Clinical and Quality Efficiency of Fractionated Cold Kits

Abstract

Background: Sentinel lymph node (SLN) mapping is a crucial diagnostic and staging tool in breast cancer, melanoma, and gynecologic malignancies. In resource-constrained public sector hospitals, high radiopharmaceutical costs, wastage, and unpredictable patient load often challenge the sustainability of SLN services. Fractionating 99mTc-nanocolloid kits offers an opportunity to improve clinical efficiency while reducing per-patient cost and minimizing radiopharmaceutical waste.

Objective: To evaluate the clinical, quality, and cost efficiency of fractionated Nanocolloid kits for pre-operative SNL visualization in a public sector tertiary hospital.

Methods: This is a cross-sectional study performed in Nuclear Medicine & Theranostics Department of Dow university of Health Sciences. Study included consecutive 51 breast cancer patients undergoing SLN mapping from April to October 2025 using fractionated ⁹⁹ᵐTc nanocolloid aliquots prepared under validated aseptic conditions at 30-45 minutes of imaging after intradermal peri-areolar injection in all four quadrants of mapping breast with mean dose of 39 ± 3 MBq. Clinical efficiency included SLN visualization rate and SLN imaging quality. Nanocolloid cold kit vial was fractionated aseptically and stored in-22^oC for use of four equal fractions in future not beyond 1 month. Radiolabeling of fractionated nanocolloid was performed as per the standard labeling protocol. Quality Control (QC) analysis included Radiochemical purity (RCP), pH, osmolality, and energy spectrum of fractionated ^99mTc-Nanocolloid were tested. Secondary outcome included cost per patient compared with standard single-batch kit use.

Results: Fractionated kit use demonstrated high clinical efficacy, with SLN visualization rates of 98%, i.e. node visualization seen in 50 out of 51. Average numbers of node visualizations were 2 ± 1 and 76% (39/51) received Neoadjuvant chemotherapy (NAC). Mean age of patient was 49 ± 9, 50 female and 1 male patients and almost equal left to right laterality. No evidence of labelling failure seen in visual interpretation. QC analysis was performed on reconstituted fractionated ^99mTc-Nanocolloid kit of a standard batch. The analyzed results of sample revealed PH=6.7 ± 0.3 (6.5-7.5), osmolality 294 mOsm/kg (250 – 350 mOsm/kg), single photo peak=147.50 (140 ±10% keV) on energy spectrum and Retention Factor 99.92% on Thin Layer Chromatography TCL (≥ 95%). 

 Conclusion: Fractionated ^99mTc-Nanocolloid kits provide clinically reliable, quality-assured, and cost-effective SLN mapping in public sector hospitals. This strategy enhances sustainability, increases patient access to diagnostic services, and aligns with resource-optimization goals in low- and middle-income health systems. Wider adoption can significantly reduce operational costs without compromising diagnostic accuracy.

Key Words: Sentinel Lymph Node mapping, Pre-operative SLN visualization, ^99mTc-Nanocolloid, Fractionated, Cost-Effective