Invasive lobular carcinoma of the breast is the second most common subtype of breast carcinoma. It accounts for 5-15% of the breast carcinoma cases reported. It shows a different metastatic pattern compared to invasive carcinoma of no special type. There are several variants of this cancer including the classic, solid, signet ring cell, tubulolobular, alveolar, trabecular, pleomorphic, and mixed subtypes each one with a distinctive morphology. Invasive lobular carcinoma has been associated with intracellular mucin production, in the form of intracytoplasmic lumina and signet ring cells whereas extracellular mucin production has been related to carcinomas of ductal origin. A new variant that displays extracellular mucin production was described recently. Only nineteen cases of this rare entity have been reported to date. In this manuscript, we report an additional case of invasive lobular carcinoma with extracellular mucin production, describing its clinico-pathological characteristics, and review the literature on the same.

Prostatic adenocarcinoma (PA) is the second most common malignancy in men globally. Signet-ring cell-like adenocarcinoma (SRCC) is a very rare PA subtype, with around 200 cases reported in the English literature. Histologically, the tumor cells show a vacuole compressing the nucleus to the periphery. Pagetoid spread in acini and ducts is usually related to metastases from urothelial or colorectal carcinomas, less commonly associated with intraductal carcinoma (IC); histologically, the tumor cells grow between the acinar secretory and basal cell layers. To our knowledge, we report the first prostatic SRCC (Gleason score 10, stage pT3b) associated with IC and pagetoid spread to prostatic acini and seminal vesicles. To our systematic literature review (PRISMA guidelines), it is the first tested case for both PD-L1 (<1% of positive tumor cells, clone 22C3) and mismatch repair system proteins (MMR) (MLH1+/MSH2+/PMS2+/MSH6+). We found no SRCC previously tested for MMR, while only four previous cases showed high expression of another PD-L1 clone (28-8). Finally, we discussed the differential diagnoses of prostatic SRCC.

Microglandular adenosis is a non-lobulocentric haphazard proliferation of small round glands composed of a single layer of flat to cuboidal epithelial cells. The glandular structures lack a myoepithelial layer; however, they are surrounded by a basement membrane. Its clinical course is benign, when it is not associated with invasive carcinoma. In around 30% of cases, there is a gradual transition to atypical microglandular adenosis, carcinoma in situ, and invasive breast carcinoma of several different histologic subtypes, including an invasive carcinoma of no special type, metaplastic matrix-producing carcinoma, secretory carcinoma, metaplastic carcinoma with squamous differentiation, acinic cell carcinoma, spindle cell carcinoma, and adenoid cystic carcinoma. Recent molecular studies suggest that microglandular adenosis is a non-obligate precursor of triple-negative breast carcinomas. In this manuscript, we present a unique case of microglandular adenosis associated with metaplastic matrix-producing carcinoma and HER-2 neu oncoprotein positive pleomorphic lobular carcinoma in situ with apocrine differentiation in a 79-year-old patient.

Salivary gland adenocarcinoma not otherwise specified (NOS) is a malignant epithelial tumor composed of ductal/glandular structures with or without cystic formation. Histologically it is classified as high grade with relevant biological behavior. Although both minor and major glands may be involved, the majority (60%) implicate the parotid gland. Location, regional lymph node status, and histological grade are some of the factors that predict the progress of the disease and the development of metastases. Long follow-up is considered the standard option as distant metastases (DM) may occur despite regional control. Primary sites of DM, besides lymph nodes, include bone, lung, and liver. Herein we report a unique case of a 68-year-old female with a previous history of high-grade adenocarcinoma NOS of her right parotid gland. On her biannual follow-up examination, MRI revealed an abnormal increase in the size of a known uterine leiomyoma of the posterior uterine wall. Positron emission tomography-CT (PET-CT) showed increased uptake in the uterus and lungs. On frozen section, adenocarcinoma was found at the center of the leiomyoma. Histological and immunohistochemical findings were consistent with secondary involvement by the salivary gland adenocarcinoma NOS. Treatment consisted of cyclophosphamide, adriamycin, and cisplatin with poor outcome. The patient was lost to follow-up. Review of the literature indicates that no similar case has been reported in the English literature.

Doxorubicin (DOX) is widely used for the treatment of several tumors, but considerable dose-dependent side effects on many normal tissues, including bones, have been reported. The aim of the present study was to follow for the first time the kinetics of DOX accumulation/clearance in the non-vascularized intervertebral disc (IVD), as well as to assess the drug’s biological action in the annulus fibrosus (AF) and nucleus pulposus (NP) IVD cells and tissues. DOX was administered intravenously to rabbits before the isolation of IVDs, in which DOX quantification was performed using a highly sensitive LC-HRMS/MS analytical method. The effect of the drug on IVD cells’ physiology was assessed in vitro, while IVD tissue quality post-DOX administration was studied in vivo through histological analysis. DOX delivery was found significantly lower in the IVD compared to the highly vascularized skin, declining from the outer AF to the inner NP. The low DOX concentrations reaching the IVDs had marginal effects on cells’ viability, intracellular redox status, and p38 MAPK activation, while they did not evoke cellular senescence. Most importantly, the drug did not negatively affect ECM integrity, as collagen and proteoglycan content remained stable in vitro and in vivo.