One of the most important components of any Confocal Microwave Imaging (CMI) system for breast cancer detection is the early-stage artifact removal algorithm. The early-stage artifact is composed of the incident pulse combined with the reflection from the skin-breast interface and residual antenna reverberation, and must be removed from the received signal at each antenna before further processing can take place. If the early-stage artifacts are not removed, they could potentially mask energy reflected from shallow tumors located close to the surface of the skin, and also hinder the identification of tumors located deeper within the breast. Many existing artifact removal algorithms are based on variants of the assumption that the artifact in a particular channel can be estimated and effectively removed by creating a reference waveform. This reference waveform is typically based on the average of the artifact in all channels. The artifact in a particular channel is then removed by subtracting this reference waveform from the recorded signal. More sophisticated algorithms estimate the artifact in each channel as a filtered combination of all the artifacts, and have been shown to be more robust to normal variations in skin thickness. However, increased underlying dielectric heterogeneity, as highlighted by Lazebnik et al., could result in greater variation in the early-stage artifact, making the artifact removal process much more difficult. In this paper, several existing artifact removal are examined in this context of increased dielectric heterogeneity, and based on these results, suggestions for future work are presented.