Preparation and Evaluation of Modified Mohs Paste without Starch.

Area of Science:

• Oncology
• Dermatology
• Pharmaceutical Sciences

Background:

• Mohs paste, an external preparation for surgically untreatable malignant tumors, contains zinc hydrochloride and zinc oxide starch.
• Traditional Mohs paste formulation suffers from time-dependent changes in physical properties (hardness, viscoelasticity) and liquefaction due to exudate.

Purpose of the Study:

• To overcome the limitations of conventional Mohs paste by modifying its formulation.
• To investigate a new base for Mohs paste to improve its stability and efficacy in palliative cancer treatment.

Main Methods:

• Modified Mohs paste formulation by excluding starch, identified as the cause of physical instability.
• Utilized macrogol ointment as the base for the modified Mohs paste.
• Evaluated physical properties (hardness, malleability, elongation), water-absorbing capacity, and drug release rate.

Main Results:

• The modified Mohs paste exhibited no significant changes in hardness, malleability, or elongation over time.
• Water-absorbing properties remained equivalent to the original Mohs paste, with sustained hardness after water absorption.
• The modified formulation demonstrated a 1.5-fold increase in drug release rate compared to the original paste.

Conclusions:

• The modified Mohs paste using macrogol ointment offers improved stability and reduced risk of liquefaction-associated skin damage.
• Pre-preparation of the modified Mohs paste is feasible, enhancing its clinical utility.
• The new formulation provides equivalent exudate control and enhanced tissue fixation, suggesting improved palliative care outcomes.