Amplification of Her-2/neu in breast carcinoma is associated with poor prognosis, short disease-free interval, and short survival time in both nodenegative and -positive patients. Little is known about the starting point of amplification of Her-2/ neu and how it progresses from benign to malignant breast lesions. We attempted to address these questions by evaluating amplification of Her-2/neu in benign, premalignant, and malignant lesions using fluorescence in situ hybridization (FISH). Twentysix patients with Her-2/neu-overexpressing invasive ductal carcinomas (as judged by strong immunoreactivity with Her-2/neu antibody) and coexisting lesions of ductal hyperplasia (DH), atypical ductal hyperplasia (ADH), ductal carcinoma in situ (DCIS) in the vicinity of the invasive tumor (as judged by review of the hematoxylin and eosin-stained sections), as well as metastatic carcinoma in axillary lymph nodes (mets) were selected for this study. In the primary carcinomas, a close relationship was present between overexpression as detected by immunohistochemistry (IHC) and amplification as demonstrated by FISH (85% concordance). Among these patients, amplification of Her-2/neu in ADH was demonstrated in 7 of 13 cases with ADH, and in DCIS, in 21 of 22 cases with DCIS. There was no amplification in DH or normal ductal epithelium. Significantly, in all 12 patients with synchronous positive axillary lymph nodes, there was concordant amplification of Her-2/neu in the primary and metastatic carcinoma. Amplification was consistent in multifocal metastases, despite morphological heterogeneity in some patients. Amplification ratios increased from ADH to DCIS to invasive carcinoma (P < .01, ADH versus DCIS; P < .05, DCIS versus invasive cancer), but there was no difference in amplification ratios between primary cancers and synchronous axillary metastases (P > .05). We also evaluated Her-2/neu amplification in 21 patients without Her-2/neu overexpression in their primary carcinomas (as judged by absent immunoreactivity with Her-2/neu antibody). Three showed amplification in both primary and metastatic lesions, with a low amplification ratio (approximately 2). One patient had amplification in the primary tumor but not in an axillary metastasis. Two patients exhibited slight amplification in the metastatic carcinoma (ratios 1.6 and 2), but not in their primary cancers. This FISH study indicates that amplification of Her-2/neu can emerge de novo in any stage of the disease process, from ADH to metastatic lesions, but most often appears first in ADH or DCIS. The degree of Her-2/neu amplification increases with progression to invasive carcinoma, there being no further increase in synchronous metastasis. Our data suggest that amplification of Her-2/neu appears to be mainly involved in initiation of breast oncogenesis and that its role in progression of breast cancers is uncertain. Her-2/neu, a proto-oncogene located on chromosome 17q, encodes a transmembrane tyrosine kinase with substantial homology to the epidermal growth factor receptor...

No abstract

Context.—Placental transmogrification of the lung is a term introduced to describe a peculiar histologic pattern characterized by formation of placental villuslike structures in the lung parenchyma. It has been reported to occur in association with bullous emphysema and lipomatosis. Objectives.—To study the relationship between placental transmogrification and pulmonary hamartomas. Design and Methods.—Reports of 38 cases of pulmonary hamartomas during 18 years (1982–1999) were reviewed. All histologic slides of these cases were examined for the presence of villuslike papillary projections and placenta-like structures. Hamartomas with prominent papillary projections or placenta-like structures were further investigated to assess the histogenesis and proliferation of epithelial and stromal cells. Immunohistochemical analysis was performed on paraffin-embedded tissue using monoclonal antibodies against Ki-67 and thyroid transcription factor 1 (TTF-1) and polyclonal antibodies against c-Kit antigen (a stem cell factor receptor/mast cell growth factor receptor) in conjunction with Leder stain for naphthol-ASD-chloroacetate esterase. Results.—Placental transmogrification was identified in 6 of 38 cases of pulmonary fibrochondromatous hamartomas. The histologic change consisted of an abundant myxoid or edematous fibroadipose stroma with a respiratory epithelial lining, resulting in papillary projections that resembled immature placental villi. Epithelium lining the papillary projections was positive for TTF-1 (70%–90%) and Ki-67 (3%–5%). In contrast, stromal cells were negative for TTF-1 with only rare cells immunoreactive for Ki-67. A number of stromal spindle cells and occasional cells in epithelium were c-Kit immunoreactive; however, concurrent Leder stain demonstrated that these c-Kit–positive cells were mast cells and not stem cells. Conclusions.—Placental transmogrification is frequently associated with pulmonary fibrochondromatous hamartomas and may be induced by or associated with a proliferation of lining epithelial components in the hamartomas. The significance of numerous mast cells within stroma of placental transmogrification is unclear and their possible role in inducing stromal proliferation needs to be further evaluated.

No abstract

Molecular markers of ordinary invasive ductal carcinoma of the breast have been extensively studied and their prognostic significance has been assessed. A common variant of breast cancer, tubular carcinoma, has an excellent prognosis as judged from several clinicopathologic studies. One would assume that tubular carcinomas have "favorable" molecular markers, however, published series of tubular carcinomas do not include molecular markers. We describe the molecular markers of 39 consecutive tubular carcinomas collected between January 1995 and July 1997. DNA ploidy, S-phase, estrogen and progesterone receptor (ER and PR, respectively) expression, and immunoreactivity for MIB-1, p53, and erbB2 were evaluated. Seventy-two percent of tubular carcinomas were DNA diploid, 49% had an S-phase less than 5%, 95% were ER positive, 69% were PR positive, 88% had less than 10% MIB-1-positive cells, 97% were p53 negative, and 97% did not overexpress erbB2 protein. Thus tubular carcinomas exhibit favorable molecular characteristics, which may play a role in their good prognosis.