If it is just the "(MHC)" at the end of the string you want to remove, this would do:
<xsl:value-of select="
substring-before(
concat(Name, '(MHC)'),
'(MHC)'
)
" />
If you want to replace dynamically, you could write a function like this:
<xsl:template name="string-replace">
<xsl:param name="subject" select="''" />
<xsl:param name="search" select="''" />
<xsl:param name="replacement" select="''" />
<xsl:param name="global" select="false()" />
<xsl:choose>
<xsl:when test="contains($subject, $search)">
<xsl:value-of select="substring-before($subject, $search)" />
<xsl:value-of select="$replacement" />
<xsl:variable name="rest" select="substring-after($subject, $search)" />
<xsl:choose>
<xsl:when test="$global">
<xsl:call-template name="string-replace">
<xsl:with-param name="subject" select="$rest" />
<xsl:with-param name="search" select="$search" />
<xsl:with-param name="replacement" select="$replacement" />
<xsl:with-param name="global" select="$global" />
</xsl:call-template>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$rest" />
</xsl:otherwise>
</xsl:choose>
</xsl:when>
<xsl:otherwise>
<xsl:value-of select="$subject" />
</xsl:otherwise>
</xsl:choose>
</xsl:template>
Which would be callable as:
<xsl:call-template name="string-replace">
<xsl:with-param name="subject" select="Name" />
<xsl:with-param name="search" select="'(MHC)'" />
<xsl:with-param name="replacement" select="''" />
<xsl:with-param name="global" select="true()" />
</xsl:call-template>