Invasive micropapillary carcinoma:A distinct type of adenocarcinomas in the gastrointestinal tract

Invasive micropapillary carcinoma (IMPC) is a rare histological type of tumor, first described in invasive ductal breast cancer, than in malignancies in other organs such as lungs, urinary bladder, ovaries or salivary glands. Recent literature data shows that this histological lesion has also been found in cancers of the gastrointestinal system. The micropapillary components are clusters of neoplastic cells that closely adhere to each other and are located in distinct empty spaces. Moreover, clusters of neoplastic cells do not have a fibrous-vascular core. The IMPC cells show reverse polarity resulting in typical ‘’inside-out’’ structures that determines secretary properties, disturbs adhesion and conditions grade of malignancy in gastrointestinal (GI) tract. Invasive micropapillary carcinoma in this location is associated with metastases to local lymph nodes and lymphovascular invasion. IMPC can be a prognostic factor for patients with cancers of the stomach, pancreas and with colorectal cancer since it is related with disease-free and overall survival. The purpose of this review is to present the characterization of invasive micropapillary carcinoma in colon, rectum, stomach and others site of GI tract, and to determine the immunohistological indentification of IMPC in those localization.

MTDH Expression in Invasive Micropapillary Carcinoma of the Breast

OBJECTIVE To clarify the expression of MTDH in invasive micropapillary carcinoma of the breast （IMPC） and analyze the relationship between MTDH expression and clinicalpathologic parameters of the IMPC patietns.

Relationship between Lymphatic Vessel Density and Lymph Node Metastasis of Invasive Micropapillary Carcinoma of the Breast

OBJECTIVE To investigate the relationship between lymphatic vessel density and lymph node metastasis of invasive micropapillary carcinoma (IMPC) of the breast. METHODS The immunohistochemical study for vascular endothelial growth factor-c (VEGF-C), VEGF Receptor-3 (VEGFR-3) and lymphatic vessel density of 51 cases of IMPC were performed, and lymph node metastases were examined by microscopic analysis of these cases. RESULTS In IMPC, VEGF-C was expressed in the cytoplasm and/or on the membrane of the tumor cells, and the expression of VEGF-C showed a positive correlation with lymph node metastasis (P<0.01). Lymphatic vessel density was determined by the number of micro-lymphatic vessels with VEGFR-3 positive staining. Lymphatic vessel density was positively correlated with VEGF-C expression (P<0.01) and lymph node metastasis (P<0.01). The percentage of IMPC in the tumor was not associated with the incidence of lymph node metastasis. The metastatic foci in lymph nodes were either pure or predominant micropapillary carcinoma. CONCLUSION The results suggested that VEGF-C overexpression stimulated tumor lymphangiogenesis, and the increased lymphatic vessel density may be the key factor that influenced lymph node metastasis of IMPC.

Clinical Value Analysis of Ultrasonography and MRI in Diagnosis of Invasive Micropapillary Carcinoma of Breast

Objective:To investigate the diagnostic value of invasive micropapillary carcinoma(IMPC)by ultrasonography and MRI.Method:63 female patients with IMPC were selected,all of which were confirmed by pathological examination,and were assigned to the IMPC group.In the same period,40 patients with invasive ductal carcinoma(IDC group)were selected for diagnostic efficacy control.The efficacy indexes of accuracy,sensitivity,specificity,positive prediction rate and negative prediction rate were 73.0%,65.9%,89.5%,93.5%,46.9%,respectively.The efficiency indexes of accuracy,sensitivity,specificity,positive prediction rate and negative prediction rate of ultrasound combined with breast MRI were 93.6%,93.2%,94.7%,97.6%,85.7%.Ultrasonography combined with MRI has more application value in the diagnosis of IMPC.

sLe^(x) expression in invasive micropapillary breast carcinoma is associated with poor prognosis and can be combined with MUC1/EMA as a supplementary diagnostic indicator

Objective: Mucin 1(MUC1/EMA) and sialyl Lewis X(sLe^(x)) indicate polarity reversal in invasive micropapillary carcinoma(IMPC). The purpose of this study was to evaluate the expression of MUC1/EMA and sLe^(x) and to assess their diagnostic and prognostic value in patients with IMPC.Methods: The expression of sLe^(x) and MUC1/EMA in 100 patients with IMPC and a control group of 89 patients with invasive ductal carcinoma not otherwise specified(IDC-NOS) were analyzed with IHC. Fresh tumor tissues were collected from patients with IMPC or IDC-NOS for primary culture and immunofluorescence analysis.Results: The rate of nodal metastasis was higher in patients with IMPC than those with IDC-NOS, and IMPC cells tended to express more sLe^(x) and MUC1/EMA in the cytomembranes(the stroma-facing surfaces of the micropapillary clusters) than IDC-NOS cells. In IMPC, high cytomembrane expression of sLe^(x), but not MUC1/EMA, indicated poor prognosis. In addition, among the 100 patients with IMPC, 10 patients had sLe^(x)+/EMA-expression patterns, and 8 patients had sLe^(x)-/EMA+ expression patterns. The primary IMPC cells were suspended, non-adherent tumor cell clusters, whereas the primary IDC cells were adherent tumor cells. Immunofluorescence analysis showed that MUC1/EMA and sLe^(x) were co-expressed on the cytomembranes in IMPC cell clusters and in the cytoplasm in IDC-NOS cells.Conclusions: sLe^(x) can be used as a prognostic indicator and can be combined with MUC1/EMA as a complementary diagnostic indicator to avoid missed IMPC diagnosis.

Prognosis of lymphotropic invasive micropapillary breast carcinoma analyzed by using data from the National Cancer Database

Background:Invasive micropapillary carcinoma(IMPC)is an uncommon subtype of breast cancer.Previous studies of this subtype demonstrated a higher propensity for lymph node metastases as compared with invasive ductal carci-noma(IDC).The purpose of the present study was to determine the clinical characteristics,outcomes,and propensity for lymph node metastasis of patients with IMPC of the breast recorded in the National Cancer Database(NCDB).Methods:Records of patients with IMPC diagnosed between 2004 and 2014 were retrieved from the NCDB.Log-rank test was performed to evaluate associations of clinical characteristics with overall survival(OS).Cox proportional hazards model was used to determine variables associated with OS.Results:Overall,2660 patients with IMPC met the selection criteria;the 5-year OS rate was 87.5%and 24.9%of patients had nodal involvement at presentation.Patients with≥4 positive lymph nodes had shorter OS than node-negative patients,whereas patients with 1-3 positive nodes had similar OS to node-negative patients.Age<65 years,receipt of radiotherapy,and estrogen receptor positivity were also associated with prolonged OS.The benefit of radiotherapy was limited to IMPC patients undergoing lumpectomy;there was no benefit for the patients undergoing mastectomy(regardless of nodal positivity/negativity).Conclusions:Favorable prognostic factors of IMPC patients included age<65 years,<4 positive lymph nodes,receipt of radiotherapy,and estrogen receptor positivity.The results presented herein suggest a survival benefit asso-ciated with radiotherapy in IMPC treatment,though this may be limited to the patients treated with lumpectomy.