HRPT2, encoding parafibromin, is mutated in hyperparathyroidism-jaw tumor syndrome.

We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors.

Is in utero early-exposure to interferon beta a risk factor for pregnancy outcomes in multiple sclerosis?

OBJECTIVE: There exist controversial and discrepant results on the risk of spontaneous abortions and teratogenesis induced by interferon treatment in people with MS.Aim of this study is to evaluate risks of the administration of INFbeta related not only to the foetus, but also to children development up to 12-months developmental milestones. METHODS: The study design is retrospective with a follow-up of babies until 18-months of their life. Thirty-eight women out of 240 with MS followed-up at Clinic MS Center of the University Hospital of Catania, Italy became pregnant in the period june 1997-may 2006. Patients were grouped into three arms: in utero exposed to INFbeta, never treated and patients who discontinued INFbeta before starting conception. Pregnancy outcomes, birth weight, 12-month developmental milestones were collected with an ad hoc questionnaire. RESULTS: Newborns of in utero exposed to INFbeta patients were little smaller for birth weight (3079.6 +/- 313.3 g), but not statistically significant, if compared with the other groups. Developmental milestones appeared within the normal range in all groups. CONCLUSIONS: Our results were particularly favourable on pregnancy outcomes, because we observed only a smaller birth weight which was not detrimental for the further development of children. We believe that INFbeta therapy might not be considered to be a reason for interruption of an intact pregnancy once the drug has been discontinued until delivery.

Ovarian cystic teratoma with primary epithelial cell melanoma.

We report a rare case of malignant melanoma arising in a cystic teratoma of the ovary occurring in a 60-year-old woman who died in four months despite the combined treatment administrated (surgery and chemotherapy). Diagnosis of ovarian melanoma was confirmed by immunohistochemical positivity to S-100 protein and HMB 45. There was no evidence of extra-ovarian primary melanoma on clinical examination; therefore the diagnosis was primary ovarian melanoma. Melanoma metastases were detected on the uterus, the right ovary, the omentum and in one of the three excised left external iliac lymph nodes. A review of the literature is analyzed and discussed.

Mucin-producing parathyroid carcinoma.

A 67-year-old white male presented with symptomatic hypercalcemia (15.6 mg/dl) in December 1989. He had undergone thyroidectomy for removal of a mucin-producing adenocarcinoma of the thyroid in 1967, and after eight years of follow-up during which time no other neoplasms were detected, he was reported as a unique case of this syndrome. Mild hypercalcemia (less than 11.0 mg/dl) was first noted in 1987, and this had remained stable until shortly before the acute presentation. Multiple lung nodules were observed radiographically and presumed to be granulomatous until increased size was observed shortly before presentation. Serum intact PTH was 190 pg/ml (n 10-55), but at neck exploration no parathyroid tissue was found and surgery did not resolve the hypercalcemia. Serum PTHrP was undetectable. Biopsies from all three lobes of the right lung revealed numerous nodules of metastatic adenocarcinoma with cords of tumor cells surrounded by mucin. The histology was similar to that obtained 23 years earlier. Following left upper lobe resection with removal of a 3-cm nodule, hypercalcemia resolved. The tumor stained strongly positive with a peroxidase stain for PTH using a polyclonal antibody. Northern blot hybridization of total RNA from the tumor confirmed the presence of message for PTH but not PTHrP. The original diagnosis has been revised to that of a unique case of mucin-producing parathyroid cancer with an extraordinarily long latency period before recurrence.

Molecular approaches to identification of tissue contamination in surgical pathology sections.

The finding of possibly contaminant tissues or cells in surgical or cytology case material can be a challenging problem in diagnostic anatomical pathology samples. The reported rates of occurrence have ranged from 0 to 8.8% (including prospective and retrospective cases). A diagnostically dissimilar tissue fragment, whether contiguous with other tissue or among other fragments within a paraffin section, and which is not incompatible with the case tissue, often requires a rigorous investigation to confirm or deny its relevance to the case. Fluorescence in situ hybridization using dual red and green DNA probes to regions of the X and Y chromosomes, respectively, were used in one case where the potential contaminant was suspected to have originated from a male patient. The putative contaminant tissue fragment was confirmed as male, with cells having one X and one Y chromosome, unlike the other tissue fragments on the slide with two X chromosomes. In a second case, DNA polymorphisms were used to compare allelic patterns that were informative not only in proving the extraneous tissue as a contaminant, but in addition, could be used to trace the latter to its original tissue source. The molecular tools of fluorescence in situ hybridization in sex-mismatched cases and of DNA microsatellite probes that are applicable to paraffin sections can provide definitive identifiers of tissues and individual cells. They are important adjuncts to histology for the anatomical pathologist when faced with the diagnostic problems of tissue contamination encountered in routine practice.

Cellular adenomyoepithelioma of the breast.

This report is the second documented case of an adenomyoepithelioma arising in the breast. The neoplasm was well circumscribed and possessed cytologic features suggestive of a low-grade cancer; however, its biologic behavior remains undefined. The epithelial and myoepithelial elements are characterized ultrastructurally, and both are active participants in the neoplastic process. There are some histologic similarities of this lesion to the salivary gland epithelial-myoepithelial carcinoma; however, the growth pattern of cellular interductal proliferation of myoepithelium is unique.

Dysplasia, in situ carcinoma, and progression to invasive squamous cell carcinoma of the upper aerodigestive tract.

Invasive squamous cell carcinoma (SCC) in the upper aerodigestive tract (UADT) is usually preceded by severe keratinizing dysplasia, a manifestation of intraepithelial neoplasia. Despite the presence of surface maturation (keratosis), severe keratinizing dysplasia has a higher frequency of progression to SCC than full-thickness classic carcinoma in situ (CIS) as defined in the gynecologic tract. For this reason, we recommend that severe UADT dysplasia be combined with CIS under the rubric of "squamous intraepithelial neoplasia (SIN) grade III" to convey to the clinician the prognostic importance of these two diagnoses. Microinvasive carcinoma in the UADT includes a microfocus of submucosal invasion within 1-2 mm of the overlying epithelial basal lamina that is completely surrounded by nonneoplastic tissue. This conservative definition of microinvasion has a low risk, or no risk, for regional metastatic spread. Immunohistologic demonstration of basal lamina components is often absent in severe intraepithelial neoplasia (SIN III). Paradoxically, basal lamina is often observed in invasive SCC, especially neoplasms forming large cohesive aggregates and cords of invasive tumor. This finding negates the usefulness of basal lamina to identify microinvasive carcinoma, but its presence does appear to correlate with a low rate of progression of SCC invading with large cohesive tumor cords.

Spindle-cell carcinoma of the upper aerodigestive tract mucosa. An immunohistologic and ultrastructural study of 18 biphasic tumors and comparison with seven monophasic spindle-cell tumors.

The histogenetic origin of the spindle-cell component of spindle-cell carcinoma of the head and neck mucosa remains controversial. The spindle cells have been considered a variant growth pattern of squamous-cell carcinoma, a non-neoplastic mesenchymal reaction, and a malignant admixture of epithelial and mesenchymal neoplasm. To evaluate the spindle-cell component, we studied 25 tumors (18 biphasic and seven monophasic) by utilizing the following: an avidin-biotin complex immunoperoxidase technique with a variety of antikeratin antibodies (AE1, AE3, CAM 5.2, 35BH11, and polyclonal Dako) and a monoclonal antivimentin antibody, and an avidin-biotin alkaline phosphatase double-labeling technique to detect coexpression of keratin and vimentin. The immunohistologic staining pattern was compared with electron-microscopic studies. Eight of 18 biphasic neoplasms contained immunoreactive keratin in the spindle-cell component that was distributed focally in a minority of cells in 3 tumors and diffusely throughout five of the neoplasms. Four of seven ulcerated monophasic spindle-cell tumors devoid of histologic squamous-cell carcinoma also were keratin positive, confirming epithelial differentiation. The majority of the spindle cells in all the tumors contained vimentin intermediate filaments. In three immunoperoxidase keratin positive biphasic tumors examined with alkaline phosphatase double labeling, occasional spindle cells were found that coexpressed keratin and vimentin and were interspersed with cells expressing either intermediate filament. Electron microscopy was performed on the spindle-cell component of 13 tumors, nine biphasic and four monophasic. Of the biphasic tumors, four were immunoperoxidase keratin positive; three of these showed epithelial differentiation by electron microscopy. Five biphasic tumors were keratin negative, and three tumors had epithelial differentiation by electron microscopy. Four monophasic spindle-cell tumors were immunoperoxidase keratin positive, and one of these had epithelial features by electron microscopy. Two monophasic tumors were keratin negative and without ultrastructural evidence of epithelial features. By using a combination of immunohistochemical and electron-microscopic observations, we identified evidence for epithelial differentiation in the spindled cells in 11 of 18 biphasic tumors and four of seven monophasic spindle-cell tumors.

Colloidal iron staining in renal epithelial neoplasms, including chromophobe renal cell carcinoma: emphasis on technique and patterns of staining.

Positive staining with Hale's colloidal iron stain, or modifications thereof, is considered a diagnostic feature for chromophobe renal cell carcinoma and has been used as a discriminatory feature to differentiate it from other renal tumors. We studied colloidal iron staining in 62 cases encompassing a wide histologic spectrum of renal neoplasms (14 chromophobe renal cell carcinomas, 19 renal oncocytomas, 11 each of granular variants and conventional clear cell renal cell carcinomas, and 7 eosinophilic variants of papillary renal cell carcinoma) to investigate the specificity of the stain for chromophobe renal cell carcinoma. In cases of chromophobe renal cell carcinoma, sections from two different areas were stained to ascertain whether there was any spatial variation in staining. Influence of staining techniques on the results also was investigated by staining each case of chromophobe renal cell carcinoma using two different methods: the traditional Hale's and a modified Mowry's technique, which treats sections with 3% acetic acid before adding the colloidal iron. Our results show that positive staining with colloidal iron stain is not limited to chromophobe renal cell carcinoma, however, a diffuse and strong, reticular staining pattern was observed only in cases of chromophobe renal cell carcinoma (14 of 14). The staining patterns were less consistent in all other renal neoplasms and differed from the reaction observed in chromophobe renal cell carcinoma. Most renal oncocytomas (16 of 19) had focal and weak, fine dustlike positivity, and all clear cell carcinomas showed focal, coarse, dropletlike positive staining (22 of 22), in addition to a focal, coarse, bubbly pattern in 5 of 11 clear cell subtypes. Although all seven cases of the eosinophilic variant of papillary renal cell carcinoma showed strong, coarse, dropletlike staining, most of the positivity was coincident with the Perl's (prussian blue) reaction, indicating that the staining was due to hemosiderin, which is frequently present in this histologic subtype of renal cell carcinoma. Staining intensity did not vary considerably among different areas of chromophobe renal cell carcinoma, but the modified Mowry's method yielded brighter and sharper reticular staining, as compared with the Hale's method. Our results show that in the appropriate morphologic context diffuse and strong reticular positivity using the modified Mowry's colloidal iron stain method is highly characteristic for chromophobe renal cell carcinoma. Treatment of sections with 3% acetic acid before adding the colloidal iron gives technically superior staining results.

Epitheliosis of the breast. An immunohistochemical characterization and comparison to malignant intraductal proliferations of the breast.

Epitheliosis is a benign intraluminal proliferation in the breast ducts and lobules that needs to be distinguished from ductal carcinoma in situ (DCIS). The histogenesis and differentiation of cells comprising epitheliosis have been the subject of some controversy. We evaluated the expression of a high-molecular-weight keratin (34 beta E12), muscle-specific actin (HHF-35), and S-100 protein immunoreactivity in formalin-fixed sections of the breast with epitheliosis and DCIS. In 28 of 30 cases of epitheliosis, there was strong HMW keratin immunoreactivity in the streaming sheetlike intraluminal proliferations. In contrast, 35 of 40 cases of DCIS (nonpapillary and papillary) were nonreactive for HMW keratin; the other five were weakly reactive. Furthermore, in 10 cases of DCIS, some ducts had isolated or small aggregates of HMW keratin-positive benign cells on the luminal aspects of the neoplastic proliferation that were reminiscent of a pagetoid pattern. Muscle actin-stained sections were analyzed to assess myoepithelial (ME) cell participation in epitheliosis. Muscle actin-positive ME cells were present at the periphery of the involved ducts but were absent or rare within epitheliosis. The distribution of ME cells--i.e., at the periphery of the spaces involved--was similar in DCIS and epitheliosis. S-100 protein was weakly but relatively consistently expressed by epitheliosis, but all cases of DCIS were negative. Six cases of atypical ductal hyperplasia included in the study were negative for HMW keratin, muscle actin, and S-100 protein. The immunohistochemical profile of epitheliosis indicates that it is primarily an epithelial proliferation with strong HMW keratin and weak S-100 protein expression but without ME cell participation. The distinct differences in HMW keratin expression of epitheliosis and intraductal carcinoma appear to reflect a consistent antigenic difference in these two biologically distinct forms of proliferation.

Antimitochondrial antibody (113-1) in the differential diagnosis of granular renal cell tumors.

Abundant granular eosinophilic cytoplasm is a common feature of renal oncocytoma, chromophobe renal cell carcinoma, eosinophilic variant of papillary renal cell carcinoma, and the granular variant of clear cell renal cell carcinoma (RCC). Each of these entities has a unique architectural pattern and a distinctive molecular or cytogenetic profile. The chief reason for their distinction from one another is the difference in their biologic behavior. Careful and thorough light microscopic examination distinguishes most cases based on individual characteristic architectural and cytomorphologic features. However, precise characterization may be difficult in some cases because of overlapping morphologic features. We evaluated the antimitochondrial antibody 113-1 in an attempt to ascertain differences in immunostaining patterns in 57 cases of granular renal tumors, including 20 renal oncocytomas, 15 chromophobe RCCs, 13 granular variants of clear cell RCC, and nine eosinophilic variants of papillary RCC. Distinctive, and nearly exclusive, staining patterns were observed among the groups, with chromophobe RCC showing peripheral accentuation of coarse cytoplasmic granules (15 of 15), renal oncocytoma with diffuse and fine granularity (20 of 20), and granular variant of clear cell RCC with irregular cytoplasmic distribution of coarse granules (11 of 13). Staining was most intense in the eosinophilic variant of papillary RCC and was generally coarsely granular and diffuse. Staining patterns also differed in clear cell areas within chromophobe RCC and the granular variant of clear cell RCC. Although clear cells in the former group showed granular staining with peripheral accentuation, most of the clear cells in the latter lacked any staining. We conclude that, in addition to distinct cytoarchitectural features, immunostaining patterns with antimitochondrial antibody 113-1 appear to be a useful discriminatory adjunct in the complex differential diagnosis of granular renal cell tumors.

Clear cell tumor of the lung. Immunohistochemical and ultrastructural evidence of melanogenesis.

Clear cell tumors of the lung (CCTL) are rare neoplasms of uncertain differentiation. A previous study of eight CCTL demonstrated a lack of epithelial features, but their exact nature remained unknown. In the current study of nine CCTL, immunohistochemistry using preliminary enzymatic digestion showed strong reactivity with the antimelanocytic markers HMB-45 (seven cases) and HMB-50 (six cases) and focal positivity for S-100 (nine cases), neuron-specific enolase (three cases), synaptophysin (one case), and Leu-7 (one case). Staining for cytokeratin, epithelial membrane antigen, chromogranin, and glial fibrillary acid protein was uniformly negative. Frozen-section immunoreactivity for vimentin and the antimelanocytic monoclonal preparation NKI/BETEB was noted in the one CCTL for which snap-frozen tissue was available. Ultrastructural examination of three glutaraldehyde-fixed CCTL showed rare neoplastic cells containing the full spectrum of melanosomes in two, one of which also contained neurosecretory-type granules. Aberrant melanosomal forms were identified in the third case. Melanosomes were not identified in the remaining five CCTL studied from formalin- or paraffin-retrieved material. The findings indicate that CCTL exhibits melanocytic differentiation. This feature may be of considerable value in distinguishing CCTL from other clear cell neoplasms.

Ultrastructural observations on mitochondria and microvesicles in renal oncocytoma, chromophobe renal cell carcinoma, and eosinophilic variant of conventional (clear cell) renal cell carcinoma.

On light microscopic examination, the morphologically overlapping features of granular eosinophilic cytoplasm in renal oncocytoma and the eosinophilic variants of chromophobe renal cell carcinoma and conventional (clear cell) renal cell carcinoma may pose difficulties in diagnosis. We investigated the ultrastructure of 5 renal oncocytomas, 7 eosinophilic variants of chromophobe renal cell carcinoma, and 5 eosinophilic variants of conventional (clear cell) renal cell carcinoma. Special attention was paid to mitochondria and microvesicles and interrelations thereof. The electron microscopic features were correlated with the light microscopic findings. All of the tumors had abundant mitochondria. Although abundant microvesicles were present in all of the chromophobe renal cell carcinomas, scant numbers of microvesicles were also sometimes present in renal oncocytomas (2 of 5) and in the eosinophilic variant of conventional (clear cell) renal cell carcinoma (1 of 5). The mitochondria in all three types of renal neoplasms studied differed in morphology, being predominantly uniform and round with predominantly lamellar cristae in renal oncocytoma, variable in shape and size with predominantly tubulocystic cristae in chromophobe renal cell carcinoma, and swollen and pleomorphic with rarefied matrix and attenuated cristae in the eosinophilic variant of conventional (clear cell) renal cell carcinoma. Variable numbers of mitochondria in all of the chromophobe renal cell carcinomas had outpouchings of the outer membranes, some of which carried parts of inner membrane within them. These outpouchings closely resembled the nearby cytoplasmic microvesicles, as did the tubulocystic cristae of the mitochondria. Some microvesicles contained homogeneous, electron-dense, finely granular matrix, similar to that seen in mitochondria. In one of seven chromophobe renal cell carcinomas, microvesicles were present in rough endoplasmic reticulum, and in two others, mitochondria were present within some vesicles. These features strongly suggest a close relationship between the microvesicles and mitochondria. Based on the role of vesicle formation in normal mitochondriogenesis, and some of our observations, we propose that defective mitochondriogenesis may be the source of microvesicles in chromophobe renal cell carcinomas.

Basaloid squamous cell carcinoma of the head and neck. A clinicopathologic and immunohistochemical study of 40 cases.

In this study of 40 cases of basaloid squamous cell carcinoma, 83% arose in the pyriform sinus, base of tongue, tonsil, and larynx. The 35 men and five women ranged in age from 27 to 88 years (median 62). In patients for whom social habits were recorded, 24 of 26 patients were smokers and 22 of 25 drank ethanol. Most presented with stage III or IV disease. Twenty-seven patients had regional metastases at the time of presentation and 15 developed distant metastases. Seventeen patients died with disease (median survival 18 months). The tumors were composed of moderately pleomorphic basaloid cells forming nests, cords, and frequent cribriform patterns. Squamous dysplasia of surface mucosa, focal squamous differentiation within invasive basaloid squamous cell carcinoma, or foci of conventional squamous cell carcinoma were present, alone or in combination. All studied neoplasms were immunohistochemically positive for keratins with the 34 beta E12 antibody. Approximately 80% were immunoreactive using AE1/AE3 or CAM 5.2. Epithelial membrane antigen, carcinoembryonic antigen, and S100 protein were found in 83%, 53%, and 39%, respectively, of the cases. Diffuse, weak immunoreactivity for neuron-specific enolase was seen in 75% of tumors. Synaptophysin, chromogranin, muscle-specific actin, and glial fibrillary acidic protein were absent. Basaloid squamous cell carcinoma has been confused with adenoid cystic carcinoma and small cell undifferentiated carcinoma, but is usually distinguishable in routine hematoxylin and eosin-stained sections, or, in rare problematic cases, with the aid of immunohistochemical studies. Distinction is warranted because the biologic behavior of basaloid squamous cell carcinoma differs from that of both of these lesions.

Immunoreactivity for BER-EP4 in adenocarcinomas, adenomatoid tumors, and malignant mesotheliomas.

Ber-EP4 is a recently characterized monoclonal antibody directed against a cell surface glycoprotein that is putatively present on human epithelial cells but lacking on the mesothelium. To investigate the diagnostic efficacy of Ber-EP4 in distinguishing adenocarcinoma from mesothelioma, we studied formalin-fixed, paraffin-embedded sections from well-documented cases of adenocarcinoma (120 cases), adenomatoid tumor (nine cases), and malignant mesothelioma (49 cases). Of the 120 adenocarcinomas, 103 (86%) showed membranous Ber-EP4 positivity, with diffuse reactivity noted in 82 cases and focal staining in 21 cases. Reactivity with Ber-EP4 was also observed in two of nine adenomatoid tumors (22%) and 10 of 49 mesotheliomas (20%). Staining in the mesotheliomas was restricted to epithelioid areas and generally focal. In one mesothelioma, however, Ber-EP4 stained the majority of neoplastic cells. In contrast to previous reports, we conclude that positivity with Ber-EP4 does not exclude the diagnosis of mesothelioma. Nonetheless, most Ber-EP4-positive mesotheliomas exhibit only focal positivity, as opposed to the extensive staining commonly observed in adenocarcinomas. Ber-EP4 has diagnostic utility in the discrimination of mesothelioma from adenocarcinoma, but it is best utilized in an antibody panel that includes other markers of carcinomatous differentiation.

Cutaneous verruciform xanthoma: a report of five cases investigating the etiology and nature of xanthomatous cells.

Verruciform xanthoma is a rare clinicopathologic entity of uncertain etiology that occurs primarily in the oral mucosa. Aggregates of foam cells in the submucosal stroma or papillary dermis in association with verrucous epithelial hyperplasia are the hallmark of this lesion. Extraoral (cutaneous) occurrence of verruciform xanthoma is much rarer and has been reported mostly in the genital skin. Five cases of extraoral cutaneous verruciform xanthoma (three from the scrotum, one from the penis, and one from the nose) and one histologic "simulant" (from skin of the nose) were studied. The lesions were solitary, raised, or polypoid with cup-shaped craters filled with parakeratotic cells that blended into keratinocytes of an acanthotic and papillomatous epidermis. There was a neutrophilic infiltrate of varying intensity between plump parakeratotic cells and keratinocytes, near the surface of the epidermis. Aggregates of foam cells were present in the papillary dermis, which was highly vascular. A plasma cell predominant infiltrate was seen at the base in a bandlike fashion. Despite the architectural resemblance of verruciform xanthoma to verrucous mucocutaneous lesions related to human papillomavirus infection, it was not detected by either immunohistochemistry, in situ hybridization, polymerase chain reaction, or Southern blot analysis in any case. The foam cells were weakly positive for cytokeratin and for Factor XIIIa but negative for S-100 protein. The KP1 and Mac 387 immunostain showed focal weak staining in foam cells. We postulate that a cascade of events pursue after initial keratinocytic damage attracting neutrophils, with subsequent phagocytosis of necrotic keratinocytic debris by dermal dendrocytes, eventually leading to the ultimate manifestation of the lesion as verruciform xanthoma. The etiologic agent remains elusive, but based on our findings, we conclude that verruciform xanthoma is most likely not a human papillomavirus-associated squamoproliferative lesion and that the foam cells, a histologic hallmark of the lesion, are most likely derived from dermal dendritic cells.

Histologic and immunophenotypic evaluation of pretreatment renal biopsies in OKT3-treated allograft rejections.

The histologic features immunophenotype of intragraft mononuclear populations, and HLA-Dr expression in pretreatment formalin-fixed renal allograft biopsies were correlated with outcome of OKT3 therapy in 35 steroid resistant renal transplant rejections. Therapeutic response (63% overall) was better in pure acute cellular rejections (ACR) (13/15, 87%) than ACR with interstitial fibrosis (4/12, 33%) or with vascular injury (5/8, 62%). Intragraft T lymphocytes were more numerous in vascular rejection (mean 566/mm2) compared with pure ACR (mean 265/mm2, P = .049), and macrophages were greater in pure ACR (203/mm2) compared with ACR with interstitial fibrosis (83/mm2, P = .051). Distribution of T cells, B cells, plasma cells, and macrophages among various histologic categories was otherwise statistically similar. There was no correlation between therapeutic response to OKT3 and intragraft concentrations of individual mononuclear cell subsets. Vascular and/or epithelial HLA-Dr expression was present in 17/25 (68%) cases and was not associated with histologic features or treatment response. Follow-up graft function (median 7 months) correlated significantly with therapeutic response to OKT3 (P = .0004) and histologic presence of interstitial fibrosis (P = .031), but was not related to concentration of individual mononuclear subsets or HLA-Dr expression. We conclude that intragraft concentrations of major mononuclear cell types may relate to histology, but that these do not predict treatment response or graft outcome, and thus poorly reflect intensity or possible heterogeneity of host immunologic rejection mechanisms.

The histologic spectrum of apocrine breast proliferations: a comparative study of morphology and DNA content by image analysis.

Apocrine features occurring in sclerosing adenosis (apocrine adenosis), atypical ductal hyperplasia (ADH), and non-comedo ductal carcinoma in situ (DCIS) often add to diagnostic difficulty. We have evaluated the usefulness of DNA content determined by image analysis in apocrine metaplasia and hyperplasia, apocrine adenosis, ADH, DCIS, lobular carcinoma in situ, invasive ductal carcinoma, and infiltrating lobular carcinoma as a potential diagnostic aid in some of these problematic breast lesions with apocrine features. Infiltrating ductal carcinoma and DCIS were further subdivided into high- or low-grade category based on nuclear features. Microscopic fields containing 63 lesions were identified in slides from breast excisions. From each selected area 100 cells in corresponding fields in paired Feulgen-stained sections were digitized for computerized ploidy analysis with lymphocyte nuclei in the same slides serving as internal diploid controls. Aneuploidy was assessed using combined DNA index and modified Auer histogram criteria for DNA content abnormalities. There was strong association between the assessment of nuclear grade and ploidy (Fisher's exact test, P < .00001). All but one of the benign and low-grade malignant lesions (97%) were in the diploid range (six of seven apocrine metaplasia cases, three of three apocrine adenosis cases, 14 of 14 ADH cases, 10 of 10 low-grade DCIS cases, two of two lobular carcinoma in situ cases, and two of two infiltrating lobular carcinoma cases). In contrast, 24 of 25 (96%) of the high-grade malignant lesions were aneuploid (10 of 10 DCIS cases and 14 of 15 infiltrating ductal carcinoma cases). We conclude that DNA ploidy status does not offer additional diagnostic information to light microscopy in distinguishing among benign apocrine proliferations, ADH, and low-grade DCIS since these proliferations share a diploid range DNA content.

Distribution of basement membrane in squamous cell carcinoma of the head and neck.

The immunohistologic distribution of the basement membrane components, type IV collagen and laminin, was evaluated in 57 alcohol-fixed, paraffin-embedded tissue sections which demonstrated immunostaining patterns with antigen preservation similar to that of frozen tissue sections. Normal and hyperplastic squamous mucosa, a spectrum of intraepithelial neoplasia, and invasive squamous cell carcinomas of the upper aerodigestive tract were evaluated by this technique. Prominent and continuous basement membrane staining characterized normal and reactive hyperplastic squamous mucosa. The basement membrane varied greatly with epithelial dysplasia and was usually prominent and continuous in mild to moderate dysplasias. In severe dysplasia/carcinoma in situ, the basement membrane was often thinned and occasionally discontinuous. The distribution of basement membrane in invasive carcinomas was also varied. Basement membrane was usually present in invasive tumors with well-defined tumor host borders and cohesive patterns of stromal invasion which were interpreted as foci of histologic differentiation. In contrast, invasive carcinomas with irregular cords or single tumor cells distributed through the host stroma invariably lacked basement membrane at the tumor-stromal interface; this was interpreted as a decreased expression of histologic differentiation. We conclude that 1) severe intraepithelial neoplasia is often associated with irregularities of basement membrane and that the absence of basement membrane does not necessarily define invasive cancer; 2) immunolocalization of basement membrane in invasive carcinomas is common in areas displaying histologic differentiation; and 3) the association of basement membrane distribution and histologic pattern of tumor invasion suggests that squamous cell carcinomas are capable of undergoing focal histologic differentiation after invasion has occurred.

A comparative immunohistochemical study of peritoneal and ovarian serous tumors, and mesotheliomas.

The distinction between serous neoplasms of the peritoneum in women and conventional mesothelioma can be difficult. In order to determine any significant immunohistochemical differences, formalin-fixed, paraffin-embedded sections of 10 peritoneal serous tumors (PST), 10 ovarian serous tumors (OST), and 10 epithelial mesotheliomas were evaluated with a panel of 10 antibodies directed against carcinoembryonic antigen (CEA: polyclonal, monoclonal), high molecular weight keratin (34 beta E12), low molecular weight keratin (35 beta H11), Leu-M1, TAG-72 (monoclonal antibody B72.3), human milk fat globulin (HMFG-2), vimentin, placental alkaline phosphatase (PLAP), and S-100 protein. The antibodies CEA, Leu-M1, and B72.3 had the most discriminatory value in differentiating serous tumors from mesothelioma. Eighty-five percent of PSTs and OSTs (17 of 20) were positive with CEA, Leu-M1, and/or B72.3. None of the mesotheliomas stained for CEA or Leu-M1; three mesotheliomas had very focal positivity with B72.3 (1% or less). Vimentin, PLAP, HMGF-2, keratin, and S-100 had no significant discriminatory value. Epithelial mucin was present in 80% of serous tumors, while the mesotheliomas lacked epithelial mucin. Leu-M1, CEA, and/or B72.3 positivity in a peritoneal tumor supports a diagnosis of serous tumor. However, since some PST do not stain for any of the three antibodies and the focal nature of positive reactions in some cases may be difficult to interpret, exclusion of mesotheliomas is enhanced by the use of mucin stains.