The 3-layered Ductal Breast Epithelium

Incipient gynecomastoid hyperplasia of the female breast. A, The duct shows a 3-layered epithelial pattern: an inner layer of luminal cells with smaller nuclei, an intermediate layer of luminal cells with predominantly vertical orientation, and an outer layer of myoepithelial cells. B, Immunostaining for ER selectively highlights the intermediate layer. C, Immunostaining for CK5 selectively highlights the inner and outer layers.

Pagetoid involvement of a duct by ductal carcinoma in situ. A, The inner layer consists of a preexisting luminal epithelium lifted up by the in situ carcinoma cells. The intermediate layer consists of disordered neoplastic cells, with some oriented vertically. The duct is surrounded by an outer layer of myoepithelium. B, Immunostaining for CK5 shows positive staining of the inner luminal layer and the outer myoepithelial layer but not the intermediate layer comprising in situ carcinoma cells.

Da Cheuk W et al, Am J Surg Pathol 2012.

Bibliografia:

Cheuk W, Tsang WY, Chan JK. The 3-layered Ductal Epithelium in the Female Breast. Am J Surg Pathol. 2012 ;36:1738-40.

Kornegoor R. et al, The 3-layered ductal epithelium in gynecomastia. Am J Surg Pathol. 2012;36:762–768

Mutation specific antibodies: tool or dinosaur?

C'è ancora posto per la "vecchia" immunoistochimica nell' era della patologia molecolare? La risposta potrebbe essere affermativa, grazie all' introduzione di anticorpi mutazione specifici che riconoscono specificamente la proteina "mutante", e che possono essere utili soprattutto nel pre-screening dei pazienti in cui la presenza della mutazione, dal punto di vista clinico e/o istologico, e più frequentemente attesa. Inoltre, gli anticorpi mutazione specifica ci consentirebbero di "visualizzare"  le singole cellule mutate anche in un contesto morfologico eterogeneo, con potenziali ripercussioni scientifiche circa l' istogenesi e l' evoluzione morfo-molecolare delle singole neoplasie.

Bibliografia:

von Deimling A, Sahm F, Capper D. Mutation specific antibodies: tool or dinosaur? Oncotarget. 2012 Aug 30  (segnalato dal prof. G. Troncone).

Long GV. et al, Immunohistochemistry Is Highly Sensitive and Specific for the Detection of V600E BRAF Mutation in Melanoma. Am J Surg Pathol. 2012 Sep 28.

Angulo B. et al, A Comparison of EGFR Mutation Testing Methods in Lung Carcinoma: Direct Sequencing, Real-time PCR and Immunohistochemistry. PLoS One. 2012;7(8).

Park HS. et al, Immunohistochemical screening for anaplastic lymphoma kinase (ALK) rearrangement in advanced non-small cell lung cancer patients. Lung Cancer. 2012 Aug;77(2):288-92. 

Current issues in diagnostic breast pathology

On behalf of the NHS Breast Screening Programme Pathology Coordinating Group we present recommendations for terminology and diagnostic criteria for a number of key areas of practice in breast pathology where terminology can be confusing and where accurate communication will ensure appropriate clinical management. These recommendations cover columnar cell lesions and the spectrum of changes that can be seen in these epithelial proliferations, lobular neoplasia, micrometastases and isolated tumour cells in axillary lymph nodes, the use of basal/myoepithelial markers in diagnostic practice and oestrogen receptor testing in ductal carcinoma in situ.

 Dall' abstract di Walker RA. et al, Current issues in diagnostic breast pathology.

Walker RA, Hanby A, Pinder SE, Thomas J, Ellis IO; National Coordinating Committee for Breast Pathology Research Subgroup, On behalf of members of the National Coordinating Committee for Breast Pathology. Current issues in diagnostic breast pathology. J Clin Pathol. 2012 Sep;65(9):771-85.

(A) Lactational changes can be mistaken for flat epithelial atypia and (B) in some rare variants show distinct cytological atypia. The epithelium tends to be cuboidal and the presence of foamy clear cytoplasm should alert one to this diagnosis (da Walker RA. et al.).