A Case of HPV-Associated Oropharyngeal Squamous Cell Carcinoma with Block-Like, Partial Loss of p16 Expression.

BACKGROUND: Oropharyngeal squamous cell carcinoma is frequently associated with high-risk HPV infection, which confers a good prognosis. Immunohistochemistry for p16 is used as a surrogate for HPV status, but discrepant results are occasionally seen. Here, we report a case with a unique pattern of partial loss of p16. METHODS: A 63 year old male presented with a base of tongue nonkeratinizing squamous cell carcinoma and a large metastatic neck mass. The primary lesion and multiple regions of the metastatic mass were assessed with p16 immunohistochemistry, RNA in situ hybridization for high-risk HPV, and HPV16 genome sequencing. RESULTS: The primary lesion was p16 negative, and the metastatic neck mass had large, confluent regions that were either strongly p16 positive or entirely p16 negative. All of these regions were positive for high-risk HPV with identical HPV16 genomes. CONCLUSION: This unusual case illustrates a potential diagnostic pitfall, and it raises important questions regarding molecular mechanisms and prognostic implications of p16 staining in oropharyngeal squamous cell carcinoma.

The association of warthin tumor with salivary ductal inclusions in intra and periparotid lymph nodes.

A predominant theory of the much debated histogenesis of Warthin tumor (WT) is that it arises from heterotopic salivary ductal inclusions (SDI) in parotid lymph nodes (LN). If this were the case, we might expect to see an increased number of SDI in the lymph nodes of patients with WT compared to controls. To test this, we compared the prevalence of SDI in patients with WT versus those with pleomorphic adenoma (PA). Cases of WT and PA were retrieved from the case files of the Department of Pathology at the QEII Health Science Centre, Halifax, NS, Canada. We then compared the prevalence of SDI in parotid LN between patients diagnosed with WT versus PA. 46 WT and 52 PA met our inclusion criteria. WT was significantly associated with an older age at surgery (62.5 years vs 50.2 years, p = 0.001). 71.7 % of WT and 32.7 % of PA had inclusions in any LN. The presence of inclusion is a significant predictor for WT versus PA (p = 0.019). Where smoking status was available, 92.5 % of WT patients were smokers/ex-smokers, versus. 55.1 % of PA (p = 0.034 for current smokers). Among PA, 44 % of smokers had inclusions compared with 22.7 % of non-smokers. SDIs are more frequent in parotid LN from patients with WT than PA. The high proportion of smokers among WT patients is consistent with prior studies. The results support the hypothesis that WT arises from SDIs. Individuals with more SDIs may be predisposed to WT.

Sinonasal seromucinous hamartoma: a review of the literature and a case report with focal myoepithelial cells.

Seromucinous hamartoma is a benign lesion of the sinonasal tract. Since its description in 1974, only a small number of additional cases have been reported. It is composed of a proliferation of seromucinous glands and ducts within a variable fibrous stroma. The serous component typically stains positively for S100 (at least focally) and lacks p63 positive abluminal cells. The lack of myoepithelial/basal cells is an important diagnostic feature of seromucinous hamartoma; their absence could lead to an incorrect diagnosis of low-grade sinonasal adenocarcinoma. We report the case of a polypoid mass resected from the posterior nasal cavity and nasopharynx of a 54-year-old woman. The lesion contained a population of small and large glands lined by cuboidal to flattened cells within a hypocellular stroma varying from dense and sclerotic to myxoid. Additionally, there was a superficial focus of ciliated invaginated surface epithelium and glands. Throughout the lesion there were no cytologic or architectural features of malignancy. The histologic features were diagnostic of seromucinous hamartoma. Immunohistochemistry showed focal S100 positivity of the serous glands. However, in contrast to previously reported cases, the glands focally showed an outer basal layer that was calponin, p63 and actin positive. Our case demonstrates two important points. First, complete absence of p63 staining should not necessarily be a required feature in the diagnosis of seromucinous hamartoma. Second, the ciliated larger glands--in keeping with respiratory epithelial adenomatoid hamartoma (REAH)--support the suggestion that seromucinous hamartoma and REAH are a spectrum of lesions, often seen together.

Complete spontaneous regression of metastatic merkel cell carcinoma: a case report and review of the literature.

Merkel cell carcinoma (MCC) is a rare aggressive primary cutaneous neuroendocrine neoplasm with a high rate of recurrence and metastasis. We report a case of a 94-year-old woman who experienced complete spontaneous regression of metastatic MCC. Nine months after complete excision of the primary MCC on her left eyebrow, metastatic MCC was confirmed with a fine-needle aspiration of a 4-cm mass on the left side of her neck. Three months later the mass had reduced in size to 2 cm and a neck dissection was performed. Her submandibular gland, thoracic duct and 25 lymph nodes were negative for MCC. Two of the lymph nodes, the larger measuring 1.3 cm, contained extensive amounts of fibrosis, with accumulation of macrophages and other chronic inflammatory cells. The literature documents 6 similar cases of complete spontaneous regression of metastatic MCC. The mechanism for regression is not well understood and is thought to involve T-cell-mediated immune response and apoptosis.

Suffocation using plastic bags: a retrospective study of suicides in Ontario, Canada.

One hundred and ten cases of suicidal suffocation using a plastic bag were identified in the files of the Office of the Chief Coroner of Ontario, Canada, between 1993 and 1997. The records were reviewed to determine the demographic characteristics of this group compared with all cases of suicide in Ontario, the scene information, autopsy findings and toxicology results. Most suicides occurred in people over 60 years of age, with older women making up a considerable proportion of cases as compared with other methods of suicide. In 40% of cases the deceased was suffering from a serious illness. Autopsy findings were usually minimal, with facial, conjunctival and visceral petechiae present in a minority of cases. One or more drugs were detected in the blood in 92.6% of cases where toxicologic testing was performed. Benzodiazepines, diphenhydramine and antidepressants were the most common drugs found, with diphenhydramine the most common drug present at an elevated concentration. Information at the scene from "right to die" societies was uncommon. One quarter of decedents took additional measures, besides the use of drugs or alcohol, to ensure the rapidity, certainty or comfort of their death. This study further elucidates the characteristics of this uncommon method of suicide. It emphasizes additional scene findings, such as the presence of dust masks, physical restraints and modification of the plastic bag that may be of use to death investigators in determining the correct manner of death.

Randomized, prospective, controlled study comparing radical prostatectomy alone and neoadjuvant androgen withdrawal in the treatment of localized prostate cancer. Canadian Urologic Oncology Group.

PURPOSE: A prospective, multicenter, randomized study was done to test the hypothesis that neoadjuvant androgen withdrawal decreases the incidence of positive margins following radical prostatectomy for localized prostate cancer. MATERIALS AND METHODS: Observations were made of 213 patients randomized to undergo radical prostatectomy alone (101) or to receive a 12-week course of 300 mg. cyproterone acetate daily followed by surgery (112). Groups were similar at baseline in terms of clinical stage, serum prostate specific antigen and Gleason score. Of 192 patients available for efficacy analysis 9 had stage T1b, 8 stage T1c, 63 stage T2a, 36 stage T2b and 76 stage T2c disease. RESULTS: One or more positive surgical margins were found in 59 of 91 patients (64.8%) in the surgery only group compared to 28 of 101 (27.7%) in the cyproterone acetate group (p = 0.001). Patients who received preoperative therapy had a statistically significantly lower rate of apical margin involvement than those who did not (17.8 versus 47.8%, respectively, p < 0.0001). There was no statistically significant difference in surgical (p = 0.8645) or postoperative (p = 0.173) complications between the 2 groups. CONCLUSIONS: Neoadjuvant androgen withdrawal with a 12-week course of 300 mg. cyproterone acetate daily results in a lower rate of positive margins without adversely affecting postoperative recovery. The impact on patient survival will be determined by long-term followup.

Intraosseous malignant peripheral nerve sheath tumor. Report of a case and review of the literature.

We report a case of a malignant peripheral nerve sheath tumor arising in the distal femur of a 28-year-old man who had no stigmata of von Recklinghausen's disease. Roentgenograms and computed tomographic scans of the distal femur showed a single lytic intraosseous lesion with minimal soft tissue extension. Light microscopy demonstrated a tumor composed of spindle cells with myxoid areas. There was some nuclear pleomorphism and mitotic activity. The tumor cells were immunoreactive for S100 protein and neuron-specific enolase. Ultrastructurally, there were cells with long processes, which were focally invested by basal lamina. Some cells had numerous micropinocytotic vesicles. The tumor recurred in the femur 15 months following the initial curettage. Computed tomographic scan of the lungs at that time showed a nodule, which has since enlarged. Primary osseous malignant peripheral nerve sheath tumors are uncommon. A literature review revealed only 18 previous cases, the majority of which occurred in the mandible or maxilla. This is a rare case of intraosseous malignant peripheral nerve sheath tumor of a long bone, with both immunohistochemical and ultrastructural confirmation of nerve sheath differentiation.