what is considered to be a high mitotic rate

Since 2010, mitotic rate has replaced 1960's Clark Level in staging as the most accurate prognostic factor after Breslow thickness.  My impression- based on very limited knowledge- is that histologic methods to determine mitotic rate vary widely.   How much credibility does an undeniably important factor have for which standards or guidelines are as yet lacking?   Why do some pathology labs still not verify mitotic rate?   I don't know.   I talked directly with the pathologist to find out section thickness, number of sections used, 'breadloaf' sectioning, etc of my excision.   1mm obviously seems too "laborious to perform".    3mm seemed 'ok'.    See excerpt from abstract on sectioning procedures, especially the last sentence (below).   Mitotic rate is highly promising, but its interpretation remains a grey area worth closer inquiry.

Melanoma Staging: Implications of Histologic Sectioning Procedures

Balch et al1 have stated that proliferation of primary melanoma as defined by the mitotic rate is a powerful and independent predictor of survival. As a result, primary tumor mitotic rate is now a required element for the seventh edition of the American Joint Committee on Cancer melanoma staging system. We suggest that careful serial histologic sectioning of the melanoma is necessary to establish the mitotic rate with confidence. The absence of mitosis may be established with certainty only after total serial sectioning of the paraffin block, which can be laborious to perform. Alternatively, it is necessary to establish guidelines for the number of sections that need to be examined to determine the mitotic rate. Interpretation of the mitotic rate is difficult when the procedure for sectioning the paraffin block is not clearly specified.

Since 2010, mitotic rate has replaced 1960's Clark Level in staging as the most accurate prognostic factor after Breslow thickness.  My impression- based on very limited knowledge- is that histologic methods to determine mitotic rate vary widely.   How much credibility does an undeniably important factor have for which standards or guidelines are as yet lacking?   Why do some pathology labs still not verify mitotic rate?   I don't know.   I talked directly with the pathologist to find out section thickness, number of sections used, 'breadloaf' sectioning, etc of my excision.   1mm obviously seems too "laborious to perform".    3mm seemed 'ok'.    See excerpt from abstract on sectioning procedures, especially the last sentence (below).   Mitotic rate is highly promising, but its interpretation remains a grey area worth closer inquiry.

Melanoma Staging: Implications of Histologic Sectioning Procedures

Balch et al1 have stated that proliferation of primary melanoma as defined by the mitotic rate is a powerful and independent predictor of survival. As a result, primary tumor mitotic rate is now a required element for the seventh edition of the American Joint Committee on Cancer melanoma staging system. We suggest that careful serial histologic sectioning of the melanoma is necessary to establish the mitotic rate with confidence. The absence of mitosis may be established with certainty only after total serial sectioning of the paraffin block, which can be laborious to perform. Alternatively, it is necessary to establish guidelines for the number of sections that need to be examined to determine the mitotic rate. Interpretation of the mitotic rate is difficult when the procedure for sectioning the paraffin block is not clearly specified.

Since 2010, mitotic rate has replaced 1960's Clark Level in staging as the most accurate prognostic factor after Breslow thickness.  My impression- based on very limited knowledge- is that histologic methods to determine mitotic rate vary widely.   How much credibility does an undeniably important factor have for which standards or guidelines are as yet lacking?   Why do some pathology labs still not verify mitotic rate?   I don't know.   I talked directly with the pathologist to find out section thickness, number of sections used, 'breadloaf' sectioning, etc of my excision.   1mm obviously seems too "laborious to perform".    3mm seemed 'ok'.    See excerpt from abstract on sectioning procedures, especially the last sentence (below).   Mitotic rate is highly promising, but its interpretation remains a grey area worth closer inquiry.

Melanoma Staging: Implications of Histologic Sectioning Procedures

Balch et al1 have stated that proliferation of primary melanoma as defined by the mitotic rate is a powerful and independent predictor of survival. As a result, primary tumor mitotic rate is now a required element for the seventh edition of the American Joint Committee on Cancer melanoma staging system. We suggest that careful serial histologic sectioning of the melanoma is necessary to establish the mitotic rate with confidence. The absence of mitosis may be established with certainty only after total serial sectioning of the paraffin block, which can be laborious to perform. Alternatively, it is necessary to establish guidelines for the number of sections that need to be examined to determine the mitotic rate. Interpretation of the mitotic rate is difficult when the procedure for sectioning the paraffin block is not clearly specified.