BACKGROUND: Extramammary @entity4261 (EMPD) is a distinct form of @entity1489 . Invasive EMPD is relatively rare and its detailed histopathological features have not been investigated to date. METHODS: Surgical specimens were obtained from 51 @entity1 with primary invasive EMPD. Clinical data including lymph node status were retrieved from the @entity1 ' medical records. Cases were divided into subgroups according to invasion depth: dermal invasion  <= 1 mm (minimal invasion) and dermal invasion > 1 mm in depth. Histological patterns (nodular/glandular pattern or micronodular pattern), lymphatic/venous invasion, mitosis and lymph node status were compared between the two groups. RESULTS: The invasive EMPDs included 26 cases (51.0%) with dermal invasion  <= 1 mm (minimal invasion) and 25 cases (49.0%) with dermal invasion > 1 mm in depth. Lymph node @entity3 was detected in 2/26 (7.7%) @entity1 with minimally invasive EMPD. Nodular/glandular pattern (72.0%), lymphatic/venous invasion (52.0%), mitosis (88.0%) and nodal @entity3 (88.0%) were all significantly more frequent in cases with dermal invasion > 1 mm, compared to EMPDs with dermal invasion  <= 1 mm (minimal invasion) (P < 0.001). CONCLUSION: These results suggest that invasive EMPD can be divided according to invasion depth, with a cut-off depth of 1 mm. This might represent the basis for a useful, EMPD-specific staging system.

Clinicopathological study of invasive extramammary XXXX : subgroup comparison according to invasion depth.

@entity1 :: ('9606', 'Species') :: ['patients'] @entity1489 :: ('MESH:D012878', 'Disease') :: ['malignant skin neoplasm'] @entity4261 :: ('MESH:D010001', 'Disease') :: ["Paget's disease"] @entity3 :: ('MESH:D009362', 'Disease') :: ['metastasis']
@entity4261 :: (MESH:D010001,Disease) :: ['Paget's disease']
