Biomedical subjects
T J Colgan
Publications and source records attributed to T J Colgan.
Prevalence of human papillomavirus in sinonasal papillomas: a study using polymerase chain reaction and in situ hybridization.
Inverted and fungiform papillomas of the sinonasal cavity share a common origin from the Schneiderian membrane, but they differ widely in their rates of recurrence and progression to carcinoma. To determine the role of human papillomavirus in the etiology of these lesions, 15 inverted papillomas, five fungiform papillomas, and two squamous cell carcinomas associated with inverted papilloma were examined for the presence of HPV by in situ hybridization (ISH) and polymerase chain reaction (PCR). ISH was carried out on formalin-fixed, paraffin-embedded material using HPV types 6/11, 16/18, and 31/33/35 DNA probes. Tissue DNA was amplified by PCR with HPV L1 consensus primers, and the product was detected by gel electrophoresis, Southern blotting, and hybridization with type specific probes (HPV types 6/11, 16, 18). Three of 15 inverted papillomas and two of five fungiform papillomas were positive for HPV 6/11 by ISH, whereas PCR detected HPV 6/11 sequences in two of 15 inverted and three of five fungiform papillomas. Biopsies from two patients who had serial resections contained HPV 6/11 in the original lesions and all recurrences. No HPV was detected in the carcinomas by ISH, whereas PCR detected HPV 16 in one carcinoma. These findings confirm the presence of HPV DNA sequences in both inverted and fungiform sinonasal papillomas as well as in an associated squamous carcinoma. This would suggest a role for HPV in the pathogenesis of Schneiderian membrane lesions. Furthermore, our data indicate that ISH and PCR are equally sensitive in detecting HPV in sinonasal papillomas.
Paraganglioma of the vulva.
A case of vulvar paraganglioma is reported. Following presentation with vulvar pain, a 1-cm nodule was excised from the labium minus of a 58-year-old woman. Histologically, the tumor was composed of nests of round eosinophilic cells with moderately pleomorphic nuclei, beneath an intact squamous epithelium. Ultrastructural studies indicated two cell types within the neoplasm: chief cells with numerous small neurosecretory granules and peripheral slender sustentacular cells. A reticulin stain confirmed the "zellballen" nature of the neoplasm, and the neoplastic cells showed moderate argyrophilia on a Grimelius stain. The immunoperoxidase stains for chromogranin and neuron-specific enolase were strongly positive in the neoplastic chief cells. Immunostaining using anti-S-100 antibody confirmed the finding of sustentacular cells by identifying many slender cellular processes among the chief cells. These light and electron microscopic findings are diagnostic of paraganglioma, an entity not previously reported in the vulva to our knowledge.
Squamous metaplasia of the peritoneum.
The capacity of the peritoneal serosa to undergo metaplasia to müllerian-type epithelium is well recognized. We report a case of squamous metaplasia of the peritoneum that was studied by light microscopy. Immunohistochemical techniques, and electron microscopy. The pathogenesis of peritoneal squamous metaplasia is obscure, but may be a response to chronic irritation.
The topography and invasive potential of cervical adenocarcinoma in situ, with and without associated squamous dysplasia.
Thirty-eight cases of cervical adenocarcinoma in situ (ACIS) were studied to see if the topography of the ACIS and any stromal invasion by adenocarcinoma were associated with the presence (22 cases) or absence (16 cases) of squamous cervical intraepithelial neoplasia (CIN). Neither the topography of the ACIS (proximal linear extent, focality, presence of ACIS beneath the transformation zone, and circumferential extent) or the presence of invasive adenocarcinoma was associated with the presence or absence of CIN. We conclude that the course of ACIS, at least as reflected by cervical topography and invasive potential, seems to be unaffected by the coexistence of squamous neoplasia.
Detection of metastatic vulvar and cervical squamous carcinoma in regional lymph nodes by use of a polyclonal keratin antibody.
A polyclonal keratin antibody (pK), a marker for epithelial cells, was used to evaluate lymph nodes (LNs) from patients with invasive squamous carcinomas of the cervix (CxCa) or vulva (VCa) to determine whether this technique could increase the detection of metastases (mets) over that obtained by light microscopy using a routine hematoxylin and eosin (H&E)-stained slide. The LN status of 15 cases of stage 1B CxCa and 14 cases of VCa was determined using a routine H&E slide. Subsequently, all LNs were resectioned and examined using a pK immunoperoxidase stain. In 329 lymph nodes from 14 cases of CxCa and 9 cases of VCa originally classified as LN-negative, only a single met was detected by the pK technique. In five cases of VCa and one case of CxCa (121 LNs), with LN mets or LN tumor emboli on the original H&E, three additional microscopic foci of mets were detected by pK. Of the four foci of mets discovered by pK, one was visible in retrospect on the original H&E section, and all four were easily identified on examination of a serial H&E section adjacent to the pK section. These results suggest that pK stains are unlikely to significantly increase our sensitivity in detecting mets in CxCa and VCa, beyond merely further sectioning and H&E staining of nodes.
Human papillomavirus infection of morphologically normal cervical epithelium adjacent to squamous dysplasia and invasive carcinoma.
We have begun a systematic study of human papillomavirus (HPV) infection in colposcopically and/or morphologically normal epithelium of the uterine cervix. Paired biopsies were taken from the lesions (cervical intraepithelial neoplasia [CIN], condyloma, invasive carcinoma) and from the normal-appearing adjacent epithelium 3 to 5 mm from the edge of the lesion. Myometrium or ectocervical epithelium from patients who had undergone hysterectomy for reasons other than genital dysplasia or malignancy served as controls. One biopsy was examined histologically. DNA from the second biopsy was digested with Pst I, and the presence or absence of HPV was determined by Southern blotting using HPV-16 DNA as a probe. HPV was not detected in any of the 12 control samples. Of 30 patients with CIN and/or condyloma, five of 18 who were HPV-positive had either HPV-16 (three cases) or virus resembling HPV-31 (two cases) in the lesion and adjacent epithelium. Of seven patients with invasive carcinoma, four had HPV in the lesion and adjacent epithelium; two of these four patients had typical HPV-16. Such infection of apparently normal epithelium has major implications for our understanding of the pathogenesis, treatment, and follow-up of patients with cervical neoplasia.
Osteogenic sarcoma with epithelial differentiation.
This case report details an osteogenic sarcoma arising in a vertebra in which cytokeratin intermediate filaments were detected immunohistochemically with three different antibodies. This feature was present not only in the primary neoplasm but also in two local recurrences and a metastasis to the iliac bone. What is unique about this primary bone tumor, however, is the structural evidence for epithelial differentiation. Ultrastructurally, well-formed desmosomes and tonofilaments were present in all four surgically resected specimens. This tumor expands the list of soft tissue and bone tumors in which anomalous expression of intermediate filaments can occur but, more important, illustrates that changes in genetic expression of neoplasia of mesenchymal origin can result in paradoxic epithelial differentiation.