Beverly Y. Wang

p63 and TTF-1 immunostaining: A useful marker panel for distinguishing small cell carcinoma of lung from poorly differentiated squamous cell carcinoma of lung

We studied the usefulness of p63 and thyroid transcription factor-1 (TTF-1) immunostains for differentiating poorly differentiated squamous cell carcinoma (PDSCC) from small cell lung carcinoma (SCLC). We used monoclonal antibodies reactive to p63 or TTF-1 to stain 4-microns-thick sections from 30 formalin-fixed, paraffin-embedded lung biopsy and resection specimens and 7 alcohol-fixed, formalin-postfixed, paraffin-embedded cell blocks from lung fine-needle aspirations (FNAs). For p63, we used a streptavidin-biotin kit, diaminobenzidine as the chromogen, and a hematoxylin counterstain. We used automated immunostaining for TTF-1. The 37 cases included 23 SCLCs, 13 PDSCCs, and 1 carcinoma initially diagnosed as PDSCC. All 23 SCLCs were negative or, rarely, equivocal for p63; 20 (87%) of 23 were TTF-1+; nuclear staining ranged from strong and/or frequent to weak and/or uncommon. All 13 PDSCCs were TTF-1-/p63+ with intense staining of 50% to 100% of tumor cells. One case originally diagnosed as PDSCC was TTF-1+/p63-, suggestive of SCLC; after morphologic reexamination and immunostaining for neuroendocrine markers, it was reclassified as intermediate-type SCLC. TTF-1 immunostaining showed equal or increased sensitivity in alcohol-fixed cytologic cell block samples compared with formalin-fixed biopsy material; in 1 SCLC case, the biopsy specimen was TTF-1-; however, the FNA cell block stained positively. p63 and TTF-1 appear to be useful for differentiating SCLC from lung PDSCC in formalin-fixed and alcohol-fixed, formalin-postfixed material.

p63 Immunohistochemistry in the distinction of adenoid cystic carcinoma from basaloid squamous cell carcinoma.

Morphologic distinction of high-grade adenoid cystic carcinoma from basaloid squamous cell carcinoma can be difficult. Equivocal diagnoses can mislead treatment. We have investigated the possibility that immunohistochemical staining for the presence of p63, a novel epithelial stem-cell regulatory protein, could be a useful means of distinguishing these two neoplasms. Archival, routinely processed slides were subjected to citrate-based antigen retrieval, exposure to anti-p63 monoclonal 4A4, and developed with a streptavidin–biotin kit and diaminobenzidine as chromogen. p63 was detected in 100% of the adenoid cystic carcinomas (n=14) and 100% of basaloid squamous cell carcinomas (n=16). Basaloid squamous cell carcinomas consistently displayed diffuse p63 positivity, with staining of nearly 100% of tumor cells. In contrast, adenoid cystic carcinoma displayed a consistently compartmentalized pattern within tumor nests. Compartmentalization was manifested in two patterns: (1) selective staining of a single peripheral layer of p63-positive cells surrounding centrally located tumor cells that were p63-negative and (2) tumor nests consisting of multiple contiguous glandular/cribriform-like units of p63-positive cells surrounding or interspersed with p63-negative cells. p63 immunostaining constitutes a specific and accurate means of distinguishing adenoid cystic carcinoma from basaloid squamous cell carcinoma. p63 positivity in adenoid cystic carcinoma appears to be homologous to that seen in the basal and/or myoepithelial compartments of salivary gland and other epithelia, and may signify a stem-cell-like role for these peripheral cells. Diffuse p63 positivity in basaloid squamous cell carcinoma suggests dysregulation of p63-positive stem cells in poorly differentiated squamous carcinoma.

Immunohistochemical staining of GLUT1 in benign, hyperplastic, and malignant endometrial epithelia.

Aberrant expression of the facilitative glucose transporter, GLUT1, is found in a wide spectrum of epithelial malignancies. The current study describes an immunohistochemical study of GLUT1 expression in benign, hyperplastic, and malignant endometrial epithelia.

p63 and TTF-1 Immunostaining

We studied the usefulness of p63 and thyroid transcription factor–1 (TTF-1) immunostains for differentiating poorly differentiated squamous cell carcinoma (PDSCC) from small cell lung carcinoma (SCLC). We used monoclonal antibodies reactive to p63 or TTF-1 to stain 4-μm-thick sections from 30 formalin-fixed, paraffin-embedded lung biopsy and resection specimens and 7 alcohol-fixed, formalin-postfixed, paraffin-embedded cell blocks from lung fine-needle aspirations (FNAs). For p63, we used a streptavidin-biotin kit, diaminobenzidine as the chromogen, and a hematoxylin counterstain. We used automated immunostaining for TTF-1. The 37 cases included 23 SCLCs, 13 PDSCCs, and 1 carcinoma initially diagnosed as PDSCC. All 23 SCLCs were negative or, rarely, equivocal for p63; 20 (87%) of 23 were TTF-1+; nuclear staining ranged from strong and/or frequent to weak and/or uncommon. All 13 PDSCCs were TTF-1–/p63+ with intense staining of 50% to 100% of tumor cells. One case originally diagnosed as PDSCC was TTF-1+/p63–, suggestive of SCLC; after morphologic reexamination and immunostaining for neuroendocrine markers, it was reclassified as intermediate-type SCLC. TTF-1 immunostaining showed equal or increased sensitivity in alcohol-fixed cytologic cell block samples compared with formalin-fixed biopsy material; in 1 SCLC case, the biopsy specimen was TTF-1–; however, the FNA cell block stained positively. p63 and TTF-1 appear to be useful for differentiating SCLC from lung PDSCC in formalin-fixed and alcohol-fixed, formalin-postfixed material.

Immunodetection of GLUT1, p63 and phospho-histone H1 in invasive head and neck squamous carcinoma: correlation of immunohistochemical staining patterns with keratinization.

Aims : To examine invasive head and neck squamous carcinomas for expression of GLUT1, a glucose transporter and marker of increased glucose uptake, glycolytic metabolism and response to tissue hypoxia; p63, a p53 homologue that is a marker of the undifferentiated proliferative basaloid phenotype; and phospho‐histone H1, a marker of activation of the cell cycle‐promoting cyclin‐dependent kinases 1 and 2.

Very delayed cervical lymph node metastases from hyalinizing clear cell carcinoma: Report of 2 cases

Hyalinizing clear cell carcinoma (HCCC) is a rare salivary gland neoplasm most often found in the oral cavity. Although it is generally a low‐grade malignancy that is treated with wide local excision, there is a growing body of evidence pointing toward the potential for more aggressive behavior.

Immunohistochemical detection of GLUT1, p63 and phosphorylated histone H1 in head and neck squamous intraepithelial neoplasia: evidence for aberrations in hypoxia-related, cell cycle- and stem-cell-regulatory pathways

Aim : Most epithelial malignancies are characterized by multistep progression from preinvasive/intraepithelial neoplasia to invasive malignancy. Detection and grading of early squamous intraepithelial neoplasia may at times be problematic. The aim of this study was to examine the ability of immunomarkers GLUT1, phospho‐histone H1 and p63 to detect such early lesions.

Fine-needle aspiration diagnosis of synovial chondromatosis of the tibiofibular joint

We report a case of synovial chondromatosis of the tibiofibular joint in a 25-year-old woman that was diagnosed by fine-needle aspiration (FNA). The patient presented with pain in the left knee and a mass in the popliteal fossa. Synovial chondromatosis usually presents with joint symptoms and is often associated with intra-articular loose bodies, whereas presentation as a soft tissue mass is unusual and may raise the clinical suspicion of malignant neoplasm. The diagnosis is commonly confirmed by histopathologic examination of biopsy or excision of the specimen. To the best of our knowledge, this is the first case of synovial chondromatosis of a large joint successfully diagnosed by FNA. Two cases of synovial chondromatosis of the temporomandibular joint have been reported in which the diagnosis was suspected on the basis of FNA. In both these cases, the final diagnosis was established by histopathology of the excised specimens.

Ameloblastic fibrosarcoma of mandible

Ameloblastic fibrosarcoma (AFS) of odontogenic origin involving mandible is very rare, which is the malignant counterpart of ameloblastic fibroma with fibrosarcomatous differentiation in mesenchymal stroma admixed with benign ameloblastic epithelium. A 27-year-old white male presented with a rapidly expanding radiolucent mandibular body mass. Extraoral examination revealed a large firm swelling in the region of the left mandibular body. No associated lymphadenopathy or sensory/motor neurological impairment. Mandibular function and range of motion were normal. Intraoral examination revealed buccal expansion in the body of the left mandible with normal overlying mucosa. There was no abnormal mobility or displacement of the associated dentition. Radiograph demonstrated a radiolucent, multi-locular lesion with ill defined borders. CT scan displayed a bulky, erosive and enhancing lesion of the body and ramus of the mandible. Biopsy was performed and was diagnosed as AFS. The patient was successfully treated with a composite resection of the affected mandible and immediate fibular free flap reconstruction. This case review provides detailed pathological diagnostic features and differentials. Aggressive treatment of AFS, including resection with negative margins is the treatment of choice.