comedo


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comedo

[′kä·mə‚dō]
(medicine)
A collection of sebaceous material and keratin retained in the hair follicle and excretory duct of the sebaceous gland, whose surface is covered with a black dot caused by oxidation of sebum at the follicular orifice. Also known as blackhead.
References in periodicals archive ?
p53 mutations are confined to comedo type ductal carcinoma in situ of the breast: immunohistochemical and sequencing data.
Over the years, as pathologists started diagnosing more and more DCIS lesions, it became apparent that some DCIS cases were difficult to neatly classify in the noncomedo/ comedo architectural subtypes; an example of such problem cases were lesions with prominent central necrosis but low-grade cytology of the DCIS cells or lesions with high-grade cytology but cribriform or micropapillary architecture.
She informs those with minimal or no comedo necrosis and negative surgical margins that by undergoing postoperative radiotherapy they can expect only a small further reduction in risk of recurrence: an absolute 7% decrease at 8 years, as indicated by the B-17 trial results.
Necrosis has been reported in some cases, focally showing comedo pattern.
Although central necrosis is generally associated with high-grade nuclei (ie, comedo DCIS), it can also occur with DCIS of low or intermediate nuclear grade.
Nevertheless, judging from the data in this series, it might be worthwhile to consider qualifying cases with large areas of DCIS with lobular extension or comedo histology with a papillary/cribriform architecture with a note such as "invasion cannot be ruled out.
Nevertheless, patients with large foci of DCIS and lobular extension and patients with comedo histology with a papillary/cribriform architecture appear to be at a relatively increased risk, and lymph node sampling at the time of excision may be warranted.
Comedo histology required both comedonecrosis and grade 3 nuclei.
Nevertheless, in this study, the largest such study to date, there were 2 histologic features that did show a significantly increased risk of invasion; these were tumors larger than 4 mm with lobular extension and tumors with comedo histology and a papillary/cribriform architecture.
Patients with comedo ductal carcinoma in situ with a cribriform or papillary pattern or tumor involving more than 4 mm with lobular extension in breast core needle specimens are at increased risk for invasion at excision.