Invasive ductal carcinoma is the most common type of breast cancer and accounts for about 70-85% of all invasive breast carcinomas. It primarily metastasizes to the bone, lungs, regional lymph nodes, liver and brain. Most of breast cancer recurrence occurs within the first 5 years of diagnosis, particularly for ER negative disease. Gastrointestinal tract involvement is very rare and is detected in only 10% of all the cases, and it usually derives from lobular breast cancer rather than the much more common cell type of ductal breast cancer. Early diagnosis is very important because it enables prompt and adequate choice of treatment and improves patient’s long-term prognosis. In this report we describe an unusual case of obstructive jaundice caused by metastases from invasive ductal breast cancer to the lymph nodes of the hepatoduodenal ligament with extramural compression of the distal common bile duct and tumor invasion to the lumen of the duct. Our goal is to emphasize possible diagnostic pitfalls and increase the clinical awareness and the importance of intensive follow-up in patients with breast cancer, even years after the initial diagnosis.

Syndecan-1 (Sdc1) is a transmembrane heparan sulfate proteoglycan, an extracellular matrix receptor involved in intercellular communication, proliferation, angiogenesis, and metastasis. This study determined and compared Sdc1 expression in the tumor cells and stroma of 30 invasive lobular and 30 invasive ductal breast carcinomas (ILCs/IDCs), also in the axillary node metastases of ductal type, and correlated it with clinical and tumor parameters. Sdc1 was expressed in the epithelium of 90% carcinoma of both histological types. Also, it was most frequently expressed in their tumor stroma, but in ILC, stromal expression was negative in 40%. Sdc1 was expressed in 86.7% of the metastatic epithelium of IDC nodal metastases (in even 50% as high expression), while the nodal stroma was negative in 46.7%. Primary IDC showed a negative correlation between epithelial Sdc1 and progesterone receptors (PRs), whereas ILC showed a positive correlation between stromal Sdc1 and histological gradus. In the metastatic epithelium, Sdc1 was negatively correlated with a patient's age, estrogen receptors (ERs), and PRs in the primary tumors, while the stroma of metastases demonstrated a positive correlation with the focus number in primary tumors and a negative correlation with PRs in primary tumors. This research revealed identical overall epithelial Sdc1 expression in both breast carcinomas with no statistically significant difference in its stromal expression and confirmed the role of Sdc1 in the progression of both tumor types and in the development of ductal carcinoma's metastatic potential.

Syndecan-1 (Sdc1) is a transmembrane heparan-sulfate proteoglycan, an extracellular matrix receptor and a cell-matrix adhesion organiser, included in adhesion of all cell's contact surfaces. It integrates different cellular signals and signals between growth factors, and modulates cell proliferation, carcinogenesis, migration and angiogenesis. Cellular motion and invasion first require loss of the Sdc1. Sdc1 expression is lost shortly before the cell changes shape or location, which decrease adhesiveness but enhance cellular mobility and their invasive potential. Releasing of Sdc1 from the cell surface (shedding) enables tumor growth and metastasizing. Such change of the Sdc1 expression is of crucial value for transition of invasive breast carcinoma to metastatic phenotype, and it is a part of epithelial-to-mesenchymal transition (EMT). Molecules included in EMT are potential targets for anticancer pharmacotherapy and control of tumor metastasizing. Maybe proteolytic conversion from insoluble (membrane bound coreceptor) to soluble Sdc1 is trigger for turning of proliferative phase of breast cancer to invasive one, which can also be of potential diagnostic-therapeutic benefit. Stromal Sdc1 expression means not merely the simple fixation of the released Sdc1 from the epithelial cells to the stromal, but also autochthonous Sdc1 synthesis in reactive stromal fibroblasts. By interacting with heparin-binding growth factors, Sdc1 accumulates in the stroma and can contribute to proliferation of invasive tumor stroma and neoangiogenesis. In more than 70% of breast carcinomas Sdc1 is induced in stromal fibroblasts, with the significant difference in its expression between stroma of malignant and non-malignant breast tissue. Although part of breast cancers loses Sdc1, in most of them it is expressed or over-expressed, and its expression is associated with a poorer response of this cancer to chemotherapy. Studies about prognostic significance of Sdc1 in breast cancer have shown unequal results, which refers to the need for new researches on this subject.

Uvod: Karcinom dojke je izrazito heterogen tumor s još uvijek nedovoljno poznatim dijagnostičkim prognostičko-prediktivnim čimbenicima koji bi bili od potencijalne terapijske važnosti. Cilj: utvrditi osnovne epidemiološko-kliničke parametre, histološki/tumorski status, prisutnost duktalne in situ (DCIS) komponente, lobularne intraepitelne neoplazije (LIN), drugih proliferativnih lezija, status T/N, ekspresiju hormonskih estrogenskih i progesteronskih receptora (ER/PR) te onkoproteina HER2/neu u dva najčešća histološka tipainvazivnom duktalnom (IDC) i invazivnom lobularnom karcinomu (ILC) dojke, usporediti njihove međuodnose i definirati možebitne razlike. Materijal i metode: Retrospektivno je analizirano 30 IDC-a i 30 ILC-a u periodu od 01.01.2005 do 31.12.2010, arhiviranih u parafinske blokove Kliničkog zavoda za patologiju "Ljudevit Jurak" KBC-a "Sestre milosrdnice", Zagreb, Hrvatska, obrađenih i bojanih standardnim metodama. Rezultati: Većina oboljelih žena bile su u postmenopauzi. IDC-i su značajno veći (p=0,002), većeg gradusa (p<0,001), s više pozitivnih pazušnih limfnih čvorova (p=0,035), značajno češće statusa T4 (p<0,001) i N1/N2 (36,7 % vs 46,7 %), dok su ILC-i najčešće statusa N0, makar i većina njih ima pozitivne pazušne metastaze. Oba se tipa daleko najčešće prezentiraju jednim tumorskim žarištem (90 % IDC-a vs 70 % ILC-a), ali su u ILC-ima češće evidentirana 3 ili više žarišta (p=0,053). LIN je nađen u većini ILC-a (73,3 %), a niti jednom IDC-u, (p<0,001). I druge proliferativne lezije značajno su češće u ILC-u (p=0,041), dok razlika u pridruženosti DCIS-a nije nađena. Velika većina tumora obaju tipova pozitivna je na ER i PR, dok razlika u ekspresiji istih među tipovima nije utvrđena. HER/2neu je značajno češće pojačano izražen u IDC-u (p=0,003). Zaključak: Istraživanjem su definirane i donekle potvrđene izvjesne razlike IDC-a i ILC-a. Zbog iznimne kompleksnosti i heterogenosti karcinoma dojke buduća istraživanja doprinijet će rasvijetljavanju razlika među histološkim tipovima, u svrhu individualnog terapijskog pristupa i što povoljnijeg ishoda. Ključne riječi: invazivni duktalni i lobularni karcinom, kliničko-epidemiološke razlike, tumorski status, hormonski receptori, onkoprotein HER2/neu Osoba za razmjenu informacija: Dr. sc. Ivana Miše, dr. med.,