Photolabile carboxylic acid protected terpolymers for surface patterning. Part 2: Photocleavage and film patterning.

The surface properties of films made of p-methoxyphenacyl derivative terpolymers, associated with photocleavage by UV irradiation, and their optical patterning are investigated. The deprotection reaction has been monitored by UV and FTIR spectroscopy, contact angle measurements, and X-ray photoelectron spectroscopy, revealing the photoremoval of the protecting p-methoxyphenacyl group in high yields under mild conditions. Parallel and serial patterning of the films has been performed by selective irradiation through optical masks and by laser irradiation via fiber tips of a scanning near-field optical microscope, respectively. By irradiation of photolabile protected functional groups, free carboxylic groups become exposed to the surface with which fluorescent dyes and proteins can be associated specifically.

Expression of KIT (CD117) in neoplasms of the head and neck: an ancillary marker for adenoid cystic carcinoma.

Adenoid cystic carcinoma is an indolent salivary gland malignancy that is associated with a poor long-term prognosis. The distinction of adenoid cystic carcinoma from other head and neck neoplasms can occasionally be problematic, particularly in small biopsies. Recent studies suggest that KIT (CD117) might be useful as an ancillary marker for adenoid cystic carcinoma; however, the expression of KIT in other benign and malignant head and neck neoplasms, including those that might mimic adenoid cystic carcinoma, has not been well studied. Here we use two different antibodies against KIT to evaluate its expression in a series of 66 adenoid cystic carcinomas compared with its expression in 98 other neoplasms of the head and neck. Overall, 94% (n = 62) of adenoid cystic carcinomas from various anatomic sites and of various histologic subtypes were positive for at least one of the KIT antibodies, and 77% (n = 50) of adenoid cystic carcinoma cases were positive for both antibodies. This contrasted with only 8% (n = 8) of other head and neck neoplasms that were positive for both KIT antibodies (P <.001). It was of note that certain neoplasms, including pleomorphic adenoma, basal cell adenoma, polymorphous low-grade adenocarcinoma, and basal cell carcinoma, that can show histologic overlap with adenoid cystic carcinoma had significantly less KIT immunoreactivity than did adenoid cystic carcinoma (P <.001). In contrast, KIT expression did not reliably distinguish adenoid cystic carcinoma from basal cell adenocarcinoma and basaloid squamous carcinoma (P >.05). The overall sensitivity of the two KIT antibodies for adenoid cystic carcinoma was 82-89%, and the specificity was 87-88%. The findings in this study support the potential use of KIT immunoexpression for distinguishing adenoid cystic carcinoma from many other benign and malignant head and neck neoplasms.

Marginal zone B-cell lymphoma of the salivary gland arising in chronic sclerosing sialadenitis (Küttner tumor).

We report a case of extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT) type of the salivary gland arising in a background of chronic sclerosing sialadenitis. Chronic sclerosing sialadenitis is a common fibrosing chronic inflammatory lesion of the submandibular gland, which is thought to be the result of sialolithiasis, and is not associated with a systemic autoimmune disease. Salivary MALT lymphomas are typically associated with lymphoepithelial sialadenitis (LESA) in a patient with or without Sjögren's syndrome. Our case of salivary MALT lymphoma was neither preceded by Sjögren's syndrome nor accompanied by LESA. This case suggests that chronic inflammatory processes other than Sjögren's syndrome may provide a substrate for the development of MALT lymphoma.

Specific inhibition of serine- and arginine-rich splicing factors phosphorylation, spliceosome assembly, and splicing by the antitumor drug NB-506.

Specific phosphorylation of serine- and arginine-rich pre-mRNA splicing factors (SR proteins) is one of the key determinants regulating splicing events. Several kinases involved in SR protein phosphorylation have been identified and characterized, among which human DNA topoisomerase I is known to have DNA-relaxing activity. In this study, we have investigated the mechanism of splicing inhibition by a glycosylated indolocarbazole derivative (NB-506), a potent inhibitor of both kinase and relaxing activities of topoisomerase I. NB-506 completely inhibits the capacity of topoisomerase I to phosphorylate, in vitro, the human splicing factor 2/alternative splicing factor (SF2/ASF). This inhibition is specific, because NB-506 does not demonstrate activity against other kinases known to phosphorylate SF2/ASF such as SR protein kinase 1 and cdc2 kinase. Importantly, HeLa nuclear extracts competent in splicing but not splicing-deficient cytoplasmic S100 extracts treated with the drug fail to phosphorylate SF2/ASF and to support splicing of pre-mRNA substrates containing SF2/ASF-target sequences. Native gel analysis of splicing complexes revealed that the drug affects the formation of the spliceosome, a dynamic ribonucleoprotein structure where splicing takes place. In the presence of the drug, neither pre-spliceosome nor spliceosome is formed, demonstrating that splicing inhibition occurs at early steps of spliceosome assembly. Splicing inhibition can be relieved by adding phosphorylated SF2/ASF, showing that extracts treated with NB-506 lack a phosphorylating activity required for splicing. Moreover, NB-506 has a cytotoxic effect on murine P388 leukemia cells but not on P388CPT5 camptothecin-resistant cells that carry two point mutations in conserved regions of topoisomerase I gene (Gly361Val and Asp709Tyr). After drug treatment, P388 cells accumulated hypophosphorylated forms of SR proteins and polyadenylated RNA in the nucleus. In contrast, neither SR protein phosphorylation nor polyadenylated mRNA distribution was affected in P388 CPT5-treated cells. Consistently, NB506 treatment altered the mRNA levels and/or splicing pattern of several tested genes (Bcl-X, CD 44, SC35, and Sty) in P388 cells but not in P388 CPT5 cells. The study shows for the first time that indolocarbazole drugs targeting topoisomerase I can affect gene expression by modulating pre-mRNA splicing through inhibition of SR proteins phosphorylation.

A novel, noninvasive imaging technique for intraoperative assessment of parathyroid glands: confocal reflectance microscopy.

BACKGROUND: Successful surgical management of primary hyperparathyroidism requires the ability to identify and distinguish normal from abnormal parathyroid tissue. Microscopic pathologic confirmation often helps with the diagnoses and decisions regarding the extent of parathyroid resection. Confocal reflectance microscopy (CRM) is an optical method of noninvasively imaging tissue without fixation, sectioning, and staining as in standard histopathology. The goal of this study was to determine if CRM imaging could be used to distinguish normal from diseased parathyroid tissue intraoperatively. METHODS: In this study, 44 parathyroid glands from 21 patients undergoing operations for primary hyperparathyroidism were imaged immediately after excision. CRM images were compared with conventional hematoxylin-and-eosin stained sections obtained from the same gland. The percentage area occupied by fat cells was calculated in images of both normal and diseased glands. RESULTS: Characteristic microscopic features of parathyroid glands were distinguishable by CRM and correlated well with histopathology. The stromal fat content of normal and diseased glands could easily be determined. The percentage area occupied by fat cells differed significantly (P <.00001) in normal glands (average, 23.0% +/- 10.9%) and adenomatous glands (average, 0.4% +/- 0.7%). CONCLUSIONS: CRM imaging rapidly revealed microscopic features that reliably differentiated normal and diseased parathyroid glands. The success of this preliminary ex vivo study promotes interest in further development of an in situ probe for in vivo clinical diagnostic use.

Fine-needle aspiration biopsy of papillary thyroid carcinoma: diagnostic utility of cytokeratin 19 immunostaining.

BACKGROUND: Papillary thyroid carcinoma is the most common malignant neoplasm of the thyroid gland, and fine-needle aspiration biopsy (FNAB) often is the initial diagnostic method used in its detection. Prior studies have shown that immunohistochemical staining for various cytokeratins in general, and cytokeratin 19 (CK19) in particular, can be applied as an ancillary technique for diagnosing papillary thyroid carcinoma in histologic specimens. In the current study the authors assessed the diagnostic utility of CK19 to detect papillary carcinoma effectively in cytologic preparations of thyroid FNABs. METHODS: Immunocytochemical staining with CK19 was performed on cytologic aspirates from 37 papillary thyroid carcinomas and 36 other lesions of the thyroid (14 follicular adenomas, 10 multinodular goiters, 5 cases of Hashimoto thyroiditis, 6 oncocytic [Hürthle cell] neoplasms, and 1 follicular carcinoma). All cases included in the study had a corresponding histopathology specimen. RESULTS: Positive immunocytochemical reactivity for CK19 was identified in 34 of 37 papillary carcinomas and in 1 of 36 other thyroid lesions (sensitivity of 92% and specificity of 97%). Although the strongest reactivity was obtained in methanol fixed thin layer preparations, the antibody also was effective in detecting papillary carcinoma in alcohol fixed and air-dried smears. The single false-positive case was a follicular adenoma with focal areas of papillary hyperplasia. All other aspirates including those from cases of Hashimoto thyroiditis, multinodular goiter, follicular adenoma, oncocytic neoplasms, and follicular carcinoma were negative. CONCLUSIONS: CK19 is an effective, highly sensitive, and specific ancillary tool for the diagnosis of papillary carcinoma in thyroid FNABs.

Cytokeratin expression in the odontogenic keratocyst.

PURPOSE: This study attempted to identify differential cytokeratin expression in cystic jaw lesions using immunohistochemical staining. PATIENTS AND METHODS: The charts from selected patients treated between 1983 and 1994 for jaw cysts were evaluated. Twenty-four paraffinized specimens were selected randomly for investigation with 5 immunohistochemical stains. The 4 diagnostic categories included ameloblastoma, dentigerous cyst, odontogenic keratocyst (OKC), and recurrent odontogenic keratocyst in patients with nevoid basal cell carcinoma (NBCC) syndrome. The 5 immunohistochemical stains included antibodies to cytokeratins 13, 17, and 18; CAM 5.2; AE 1/3; and carcinoembryonic antigen (CEA). RESULTS: Differential staining of OKCs from patients with and without NBCC syndrome was found only with the antibody to cytokeratin 17. Furthermore, staining of OKCs in syndromic patients appeared to be stronger and more uniform than in nonsyndromic patients. CONCLUSIONS: These findings suggest that immunohistochemical staining for cytokeratin 17 may aid in the diagnosis of OKCs and may be used to further subdivide these lesions based on the presence or absence of NBCC syndrome.

Fine-needle aspiration of dedifferentiated chondrosarcoma of the larynx.

We present a case of dedifferentiated chondrosarcoma of the larynx in which the dedifferentiated component was initially diagnosed by fine-needle aspiration (FNA). The patient was a 74-yr-old man who presented with difficulty breathing and an anterior neck mass. A CT scan demonstrated a 4.5-cm cartilaginous lesion involving the left thyroid cartilage, with an anterior soft-tissue component. Nine years prior, the patient had an incomplete resection of a low-grade chondrosarcoma at the same site. FNA was performed on the current lesion, demonstrating a high-grade spindle-cell sarcoma with a storiform pattern. The cytomorphology together with immunocytochemistry and electron microscopy were diagnostic of malignant fibrous histiocytoma (MFH), and synthesis of the clinical, radiographic, and cytomorphologic features resulted in a diagnosis of dedifferentiated chondrosarcoma. The cytologic diagnosis was histologically confirmed by laryngectomy. Although rare, dedifferentiated chondrosarcoma should be included in the differential diagnosis of high-grade sarcomas of bone and cartilage assessed by FNA.

Sinonasal lymphoma: a clinicopathologic analysis of 58 cases from the Massachusetts General Hospital.

Few large series compare lymphomas of the nasal cavity with those of the paranasal sinuses. We studied the cases of 58 patients, 34 males and 24 females, aged 7 to 92 years (mean, 57 years), who had lymphoma involving the nasal cavity or paranasal sinuses. Thirty-three patients had diffuse large B-cell lymphoma (DLBCL). Twenty-three were male and 10 were female, with an age range of 7 to 91 years (mean, 63 years); two were HIV-positive. Only 2 of 11 cases tested (one in an HIV-positive patient and one of lymphomatoid granulomatosis type) were Epstein-Barr virus (EBV)-positive. Thirty (91%) involved paranasal sinuses, 10 with nasal involvement, whereas three cases had nasal, but not sinus, involvement. At last follow-up, 16 (67%) were free of disease 7 to 169 months later (mean, 65 months), and 8 (33%) had died of disease 2 to 166 months later (mean, 45 months). Seventeen patients had nasal-type natural killer (NK)/T-cell lymphoma. There were 10 women and 7 men, aged 27 to 78 years (mean, 48 years). Thirteen of 14 were EBV-positive. Sixteen patients had nasal involvement, eight with sinus involvement. Eleven (73%) of 15 were alive and well 6 to 321 months later (mean, 139 months), three (20%) died of lymphoma 1, 11, and 12 months later, and one (7%) is alive with disease. There was one case each of marginal zone B-cell lymphoma, Burkitt's lymphoma, Burkitt-like lymphoma, peripheral T-cell lymphoma of unspecified type, and adult T-cell lymphoma/leukemia. In an additional three cases, the lymphomas were composed predominantly of large cells, but no immunophenotyping could be performed for subclassification. In 19 cases (17 DLBCLs, 1 Burkitt-like lymphoma, and 1 lymphoma of uncertain lineage), presenting symptoms included complaints related to the eyes. In 16 cases (13 DLBCLs, 1 Burkitt-like lymphoma, 1 nasal NK/T-cell lymphoma, and 1 lymphoma of uncertain lineage), the orbit was invaded by lymphoma. In our series, the most common lymphoma to arise in the sinonasal area is DLBCL, followed by nasal NK/T-cell lymphoma. Comparison of these two types of lymphoma showed that lymphomas involving sinuses without nasal involvement were predominantly DLBCLs (20 of 21), whereas nasal cavity lymphomas without sinus involvement were usually NK/T-cell type (8 of 11) (p = 0.000125). Compared with patients with DLBCL, patients with nasal NK/T-cell lymphoma were overall younger, with a lower male-to-female ratio. Lymphomas of B-cell lineage were more likely to be associated with symptoms related to the eyes (p < 0.0005) and to have extension to the orbit (p < 0.01) than were lymphomas of T- or NK-cell lineage. In contrast to results of Asian studies in which nasal NK/T-cell lymphoma has a very poor prognosis, our nasal NK/T-cell lymphomas had an outcome similar to that of DLBCL.

Microscopic detection of occult malignancy in the adult tonsil.

Microscopic evaluation of all adult tonsillar specimens has been considered essential despite the low incidence of unsuspected pathologic conditions. We evaluate whether routine histologic examination of clinically benign adult tonsillar specimens is indicated. We retrospectively reviewed pathology results from all tonsillectomies performed on patients ages 18 years or older at our institution from 1989 through 1996. Three groups were created on the basis of indications for tonsillectomy: (1) routine tonsillectomies for benign disease, (2) asymmetric tonsils, and (3) search for unknown primary lesions. Demographic data and pathologic findings in each group were analyzed. In 1280 tonsillectomies performed for benign disease there were no malignancies (0%) and 32 cases (2.50%) with clinically unsuspected benign pathologic conditions. In 31 cases of tonsillar asymmetry, two cases with malignant lymphoma (6.5%) and three cases with benign pathology (9.7%) were identified. In nine patients with squamous cell carcinoma metastatic to the neck, two occult primary lesions were identified in the ipsilateral tonsil. Our results suggest that histologic evaluation of adult tonsils removed for benign disease may be clinically unnecessary. The elimination of microscopic examination of tonsils removed from patients whose clinical presentation is entirely consistent with benign disease poses minimal risk of missing clinically significant pathologic conditions. Substantial costs for negative examinations may be avoided.

CD44 expression in sinonasal inverted papillomas and associated squamous cell carcinoma.

Increased expression of the cell adhesion molecule, CD44 standard form (CD44s), has been associated with papillary epithelial tumors, and decreased expression has been linked to tumor invasion and metastasis. Sinonasal inverted papillomas (SIPs) are the most common papillary tumors of the sinonasal tract. This study tests whether the development of squamous cell carcinoma (SCC) in situ and invasive SCC in SIP is associated with altered expression of CD44s. Seventy-six specimens of SIP from 68 patients, 2 specimens of SIP with focal SCC in situ, and 10 specimens of invasive SCC arising in SIP were studied. Automated immunohistochemistry was performed for CD44s expression on paraffin-embedded tissue sections using mouse antihuman CD44 antibody. All 76 SIPs (100%) expressed CD44 (strong membranous staining, 83%; moderate staining, 12%; weak staining, 5%). Two (100%) of 2 SIPs with SCC in situ maintained strong expression in benign and severely dysplastic foci. Six (60%) of 10 SIPs with SCC showed complete loss of CD44s expression, while 4 (40%) of 10 cases of SIP with SCC showed weak expression. Two SIPs with SCC (20%) featured weak diffuse staining of the SCC component, and 2 SIPs with SCC (20%) featured weak focal staining of the SCC component. The non-SCC SIP components of the 10 SIPs with SCC uniformly featured intact membranous CD44 staining. As in other papillary epithelial neoplasms, the typical benign SIP features diffuse membranous CD44s expression. In cases of SIP developing an invasive SCC, CD44s expression in the SCC component is frequently lost.

Endocrine mucin-producing sweat gland carcinoma: a cutaneous neoplasm analogous to solid papillary carcinoma of breast.

We describe two cases of a distinctive in situ and invasive cutaneous adnexal neoplasm occurring in the eyelid. Mucinous carcinoma represented the invasive portion of the tumor in one case, whereas the other infiltrated in small solid nests. The in situ component is identical to the recently described solid papillary carcinoma of the breast (endocrine ductal carcinoma in situ). Both tumors produced intra- and extracellular mucin, exhibited endocrine differentiation by immunohistochemistry and ultrastructural analysis, and were positive for estrogen and progesterone receptors.

Eosinophilic angiocentric fibrosis of the nasal cavity.

Eosinophilic angiocentric fibrosis (EAF) is a rare condition of unknown etiology that causes stenosis of the upper respiratory tract. We report one case in which immunohistochemical studies were performed that involved the mucosa of the lateral nasal wall and septum of a 54-year-old woman. The lesion showed areas with vascular proliferation, small-vessel vasculitis, and dense inflammatory infiltrate consisting of T lymphocytes, macrophages, polyclonal plasma cells, and numerous eosinophils and neutrophils. Other areas were hypocellular and fibrotic, and in those, the collagen bundles showed perivascular onion-skin whorling. The clinical and histologic similarities between our case and those previously described, in addition to the immunohistochemical findings, support the hypothesis that eosinophilic angiocentric fibrosis is a chronic inflammatory condition with a peculiar and striking stromal response.

Differential expression of transthyretin in papillary tumors of the endolymphatic sac and choroid plexus.

Aggressive papillary tumors of the temporal bone, occurring sporadically or as part of von Hippel-Lindau disease, have been shown to originate within the endolymphatic sac or duct. Also implicated as a potential precursor from which some of these tumors may arise is ectopic choroid plexus epithelium. To aid in the differentiation between papillary tumors of endolymphatic sac and duct origin and those arising from choroid plexus, an immunohistochemical study using stains for transthyretin (TTR), cytokeratins, S-100 protein, epithelial membrane antigen (EMA), and glial fibrillary acidic protein (GFAP) was carried out on archival specimens of normal and neoplastic endolymphatic sac and duct and choroid plexus epithelium. Transthyretin, a marker for choroid plexus epithelium, was found to show differential expression between choroid plexus papillomas and aggressive papillary tumors of the endolymphatic sac or duct. Therefore the use of TTR in concert with other immunohistochemical stains appear to aid in the differentiation between intracranial and intratemporal papillary tumors arising from choroid plexus and endolymphatic sac or duct epithelium.

Endolymphatic sac tumors: histopathologic confirmation, clinical characterization, and implication in von Hippel-Lindau disease.

The term "endolymphatic sac tumor" (ELST) was coined to identify the likely origin of aggressive papillary tumors of the temporal bone. To evaluate the validity of this designation, the temporal bone collection at the Massachusetts Eye and Ear Infirmary was accessed in an effort to determine the pathologic relationship between these tumors and the endolymphatic sac. The search resulted in the identification of a de-novo papillary epithelial lesion arising within the confines of the endolymphatic sac in a patient with von Hippel-Lindau (VHL) disease who harbored a large, destructive ELST in the opposite temporal bone. This finding provides the most substantial evidence to date regarding the origin of the ELST and the accuracy of its nomenclature. Seven additional clinical cases of ELST were identified and analyzed in order to define the natural history of these tumors. All patients had a history of sensorineural hearing loss diagnosed an average of 10.6 years prior to tumor discovery. The presence of a polypoid external auditory canal mass, facial paralysis, and evidence of a destructive mass arising on the posterior fossa surface of the temporal bone were common physical and radiographic findings. The management of these patients, as well as those who are probably prone to such tumors (i.e., VHL patients), is discussed.

Polycystic disease of the parotid glands.

A 31-year-old woman had bilateral swelling of the parotid glands at 4 months of pregnancy. MR imaging showed marked enlargement of the parotid glands with increased signal on images with long repetition times. A diagnosis of polycystic disease of the parotid gland was made after biopsy and histologic examination. The radiographic and histologic features of this rare disease are discussed.

Lipofuscin pigmentation (so-called "melanosis") of the prostate.

Although intraepithelial pigment in the prostate gland has been termed melanosis, the nature of the pigment is not entirely clear, and many pathologists are not aware of its existence. We examined 863 hematoxylin and eosin (H + E) stained slides from 150 surgical specimens of prostate (69 needle biopsies, 66 transurethral resections, 14 radical prostatectomies, and 1 suprapubic prostatectomy) from 149 patients (age range, 47 to 90 years; mean 70 years) in an effort to characterize this pigment. The 1-3 microns in diameter, predominantly subnuclear, yellow-brown to gray-brown granules with a dark blue rim (by H + E) stained positively with Fontana-Masson, periodic acid-Schiff with diastase, Congo red, luxol fast blue, and oil-red-O and exhibited yellow autofluorescence consistent with lipofuscin. H + E stained slides revealed pigment in the benign epithelium in 86 of 150 cases (57%), within stromal macrophages in eight cases, and in atypical epithelium in two cases of high-grade prostatic intraepithelial neoplasia. Ten cases of invasive adenocarcinoma without recognizable pigment in H + E stained sections were stained by the Fontana-Masson technique, and pigment was identified in malignant epithelium in three of these cases. Ultrastructural examination of intraepithelial pigment in KII-fixed tissue from three radical prostatectomy specimens demonstrated the typical appearance of lipofuscin. Although intraepithelial pigment in prostatic biopsy or resection specimens is usually considered characteristic of seminal vesicle epithelium, our study demonstrates that lipofuscin is commonly present in epithelial cells of benign prostatic hyperplasia and less frequently in those of prostatic intraepithelial neoplasia and adenocarcinoma. The recognition of this pigment is important in preventing diagnostic confusion with seminal vesicle epithelium and with melanocytic lesions.

Solitary fibrous tumor of the orbit.

We report three cases of an orbital soft tissue lesion that fulfills the histologic, immunohistochemical, and electron microscopic criteria for solitary fibrous tumor, an entity previously described as a pleural tumor, but recently reported to occur in other locations. All three patients presented with proptosis. Two of the patients were cured by simple excision, and one patient had two recurrences, the last recurrence incompletely excised. The findings indicate that solitary fibrous tumor can occur in the orbit and, like solitary fibrous tumors of other anatomic sites, may behave in a nonaggressive or occasionally, locally aggressive fashion, with as yet no metastatic potential demonstrated in orbital lesions.

Hamartomas of the nose and nasopharynx.

Hamartomas are easily diagnosed entities when occurring in the lung and gastrointestinal tract. In the nose and nasopharynx, where such lesions are rare, biopsy of a hamartoma containing epithelial proliferation may lead to a misdiagnosis of cancer, with resultant radical and deforming surgery, particularly if they present in adulthood. We encountered three such lesions over 2 years in the Massachusetts Eye Ear Infirmary, and another was retrieved from the recent files. All presented with nonspecific obstructive symptoms of the nose or nasopharynx, and were treated by resection. Follow-up is short, (4 months to 1 year), but in no case has there been recurrence. The clinical diagnosis was malignancy in 2 cases, inflammatory polyp in one.