Leiomyoma of the palatine tonsil - report of a rare and unusual tumor at this site.

A leiomyoma is a remarkably rare cause of a benign, one-side tonsillar enlargement. The diagnosis is essentially histologic and will not normally be suspected clinically. Immunohistochemistry is needed for substantiation of the morphology and confirmation. We submit this illustrative case report.

Low-grade adenosquamous carcinoma of the breast: A rare case presentation.

Low-grade adenosquamous carcinoma of the breast is a rare variant of metaplastic mammary carcinoma. It shows indolent behavior contrary to the usual aggressive nature of metaplastic carcinomas and has a good prognosis despite being triple negative. Recurrence rates tend to be high and a consequence of incomplete excision. Although this variant has an infiltrative growth pattern, owing to its bland cytologic features, it is liable to be confused with benign sclerosing adenotic breast lesions. We present here a case of a 55-year-old postmenopausal female, who presented with a painless, mobile, hard, and nontender lump in the lower outer quadrant of the left breast, with normal overlying skin and nipple-areola complex. No associated axillary lymphadenopathy was seen. On mammography, a high-density mass of architectural distortion, characterized as BIRADS category 4C, was found. Core-needle biopsy showed haphazard glands lined by a double layer of epithelium and nests of squamoid cells arranged in an infiltrative fashion within a fibromyxoid stroma. On immunohistochemistry, tumor cells showed a lack of expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 receptor and were positive for CK 5/6 and CK7. There was counterintuitive, but characteristic positivity for myoepithelial markers calponin and CD 10 around the neoplastic nests and stromal cells expressed smooth muscle myosin. Subsequently, the patient underwent a wide local excision with free margins and sentinel lymph nodes were negative for tumor deposits. This patient remains well and free of recurrence well into follow-up.

Immunohistochemical subtyping of diffuse large B-cell lymphoma into germinal center B-cell and activated B-cell subtype, along with correlation of the subtypes with extranodal involvement, serum lactate dehydrogenase, and positron emission tomography scan-based response assessment to chemotherapy.

Context: Diffuse large B-cell lymphoma (DLBCL) is the most common type of non-Hodgkin lymphoma in Indian population and is divided into the prognostically important subtypes, germinal center B-cell (GCB) and activated B-cell-like (ABC), using immunohistochemistry-based algorithm. Aim: The present study aims to evaluate the influence of immunohistochemical derived DLBCL subtype, GCB or ABC on prognostically significant variables - extranodal involvement and serum lactate dehydrogenase (LDH) level at presentation, and response to chemotherapy assessed on pre- and posttreatment fluorodeoxyglucose-positron emission tomography study. Settings and Design: This was a retro-prospective, 2-year observational study at a tertiary health-care center, New Delhi. Subjects and Methods: The study population includes a total 236 cases of DLBCL. According to the Hans algorithm, DLBCL cases were allocated to the GCB and ABC subgroups. Statistical Analysis Used: For comparison of mean values, independent t-test and analysis of variance were used. For this purpose, we used SPSS 20.0 software. P < 0.05 was considered as statistically significant. Results: Ninety-eight patients (41.5%) had GCB immunophenotype and 138 patients (58.5%) were ABC. A significant difference was observed between mean baseline level of LDH between GCB and ABC subtypes (P < 0.05). The proportion of cases with extranodal involvement was comparatively higher in ABC subtype (P < 0.05). Association between response to chemotherapy with DLBCL immunophenotypes was found to be highly significant (P < 0.00). The response rates were much better in GCB subtype. Conclusions: The mean baseline level of LDH is significantly higher in ABC subtype. The proportion of cases with extranodal involvement was comparatively higher in ABC and shows poor response to chemotherapy as compared to GCB. Baseline LDH level was found to be important prognostic marker in the DLBCL.

Primary diffuse large B-cell lymphoma masquerading as uterine fibroid: A pathologistsf diagnosis.

Lymphoma involving the uterus is rare, and the diagnosis is usually difficult due to the rarity and nonspecific presentation. The treatment is often delayed and difficult because there is no standard treatment. We report our experience with a case of diffuse large B-cell lymphoma (DLBCL) involving the uterus. A 40-year-old female presented to our hospital posthysterectomy for suspected fibroid. Computed tomography scan and the tissue biopsy along with the immunoprofile revealed uterine DLBCL. She was treated with chemotherapy followed by radiation therapy and showed the complete response to the treatment, and thus, the clinicians should be aware of this rare disease for prompt diagnosis.

Urethral metastasis with neuroendocrine differentiation in a patient with prostate cancer treated with hormone deprivation.

Adenocarcinoma prostate treated with hormone deprivation may evolve into a neuroendocrine differentiated tumor. Usually visceral metastasis are seen in neuroendocrine tumors. We present a case of neuroendocrine differentiated urethral metastasis from a hormone deprived prostate cancer.

Metastasis to a spinal meningioma.

BACKGROUND: Metastasis of one cancer to another is rare. Here, we report a spinal meningioma that was infiltrated by metastatic deposits from another cancer. CASE DESCRIPTION: A 62-year-old male presented with a progressive spastic paraparesis. Magnetic resonance (MR) imaging of the spine suggested a well-defined intradural extramedullary (IDEM) T8 mass in the dorsal spinal canal. When excised, it proved histologically to be a meningothelial meningioma infiltrated by metastatic deposits from an adenocarcinoma. CONCLUSION: Tumor to tumor metastasis rarely occurs, and meningioma, owing to its biological character and increased vascularity, is one of the most common recipients of a metastases from other lesions.

Expression of proto-oncogene KIT is up-regulated in subset of human meningiomas.

BACKGROUND: KIT is a proto-oncogene involved in diverse neoplastic processes. Aberrant kinase activity of the KIT receptor has been targeted by tyrosine kinase inhibitor (TKI) therapy in different neoplasias. In all the earlier studies, KIT expression was reported to be absent in meningiomas. However, we observed KIT mRNA expression in some meningioma cases. This prompted us to undertake its detailed analyses in meningioma tissues resected during 2008-2009. METHODS: Tumor tissues and matched peripheral blood samples collected from meningioma patients were used for detailed molecular analyses. KIT expression was ascertained immunohistochemically and validated by immunoblotting. KIT and KITLG transcript levels were discerned by reverse transcription quantitative real-time PCR (RT-qPCR). Similarly, KIT amplification and allele loss were assessed by quantitative real-time (qPCR) and validated by fluorescence in situ hybridization (FISH) on the neoplastic tissues. Possible alterations of the gene at the nucleotide level were analyzed by sequencing. RESULTS: Contrary to earlier reports, KIT expression, was detected immunohistochemically in 20.6% meningioma cases (n = 34). Receptor (KIT) and ligand (KITLG) transcripts monitored by RT-qPCR were found to co-express (p = 0.048) in most of the KIT immunopositive tumors. 1/7 KIT positive meningiomas showed allele loss corroborated by reduced FISH signal in the corresponding neoplastic tissue. Sequence analysis of KIT showed M541L substitution in exon 10, in one of the immunopositive cases. However, its biological consequence remains to be uncovered. CONCLUSIONS: This study clearly demonstrates KIT over-expression in the human meningiomas. The data suggest that up-regulated KIT transcription (p < 0.001), instead of gene amplification (p > 0.05), is a likely mechanism responsible for altered KIT expression. Thus, KIT is a potential candidate for detailed investigation in the context of meningioma pathogenesis.

Primary dural follicular lymphoma masquerading as meningioma: a case report.

Patient presented with a dural-based mass lesion and was diagnosed as having meningioma on imaging. Post-resection histological examination revealed a low grade follicular lymphoma. The patient received cranial radiotherapy and is recurrence-free at 6-month follow-up. Primary dural follicular lymphoma is an exceedingly rare entity with only as few as six reported cases. Herein, the clinico-radio-pathological appearances and treatment protocol of this entity are discussed.

A subset of human gliomas shows over-expression of KIT without its amplification.

Receptor tyrosine kinase (RTK) encoded by proto-oncogene KIT is known to be involved in different types of cancers. Reportedly, KIT expression has been associated with higher grade of gliomas. Initial RT-PCR based KIT expression observed in low grade glioma cases evoked our interest to ascertain its status in glioma patients who underwent resection during 2008-2009. Contrary to earlier reports, over-expression of the RTK was observed in 32.5% glioma cases across low/high grades (n=40). Using quantitative PCR (qPCR), an up-regulation of the receptor (KIT) and its ligand (KITLG) was detected in most of the immunopositive cases at the transcript level. Sequence analysis of KIT showed two nucleotide substitutions in exons 10 and 17, in 4 and 2 cases, respectively though their pathological significance remained unclear. qPCR detected gene amplification in 2/13 glioma and allele loss in 1/13 glioma cases. This was in accordance with FISH results of these KIT positive neoplastic tissues. The data suggest that deranged expression of KIT is independent of gene amplification (p>0.05). Aberrant KIT expression is significantly associated with transcriptional up-regulation (p<0.001), though the precise mechanism(s) for transcriptional activation remain unclear.

Localisation of SCN10A gene product Na(v)1.8 and novel pain-related ion channels in human heart.

We have shown that the gene SCN10A encoding the sodium channel Na(v)1.8 is a susceptibility factor for heart block and serious ventricular arrhythmia. Since Na(v)1.8 is known to be present in nerve fibres that mediate pain, it may be related to both cardiac pain and dysrhythmia. The localisation of Na(v)1.8 and other key nociceptive ion channels, including Na(v)1.7, Na(v)1.9, capsaicin receptor TRPV1, and purinergic receptor P2X(3), have not been reported in human heart. The aim of this study was to determine the distribution of Na(v)1.8, related sodium and other sensory channels in human cardiac tissue, and correlate their density with sympathetic nerves, regenerating nerves (GAP-43), and vascularity. Human heart atrial appendage tissues (n = 13) were collected during surgery for valve disease. Tissues were investigated by immunohistology using specific antibodies to Na(v)1.8 and other markers. Na(v)1.8 immunoreactivity was detected in nerve fibres and fascicles in the myocardium, often closely associated with small capillaries. Na(v)1.8 nerve fibres per mm(2) correlated significantly with vascular markers. Na(v)1.8-immunoreactivity was present also in cardiomyocytes with a similar distribution pattern to that seen with connexins, the specialised gap junction proteins of myocardial intercalated discs. Na(v)1.5-immunoreactivity was detected in cardiomyocytes but not in nerve fibres. Na(v)1.7, Na(v)1.9, TRPV1, P2X(3)/P2X(2), and GAP43 positive nerve fibres were relatively sparse, whereas sympathetic innervation and connexin43 were abundant. We conclude that sodium channel Na(v)1.8 is present in sensory nerves and cardiomyocytes of human heart. Na(v)1.8 and other pain channels provide new targets for the understanding and treatment of cardiac pain and dysrhythmia.

Pseudoangiomatous stromal hyperplasia (PASH) tumour at the surgical scar site in a patient of carcinoma breast.

A patient on follow-up post surgery for carcinoma breast, presented with a nodule under the surgical scar. The sinister eventuality of recurrent carcinoma was clinically considered first. The lesion was biopsied and the histopathology was diagnostic of pseudoangiomatous stromal hyperplasia tumour. The nodule was excised and the patient's clinical denouement has been uneventful in the 4 months which have elapsed after this event.

Juvenile psammomatoid ossifying fibroma: a rare cause of unilateral proptosis.

This is case of a young girl who presented with unilateral proptosis. Imaging (CT & MRI) revealed an expansile lytic bony tumour involving the left frontal bone and orbital roof. The globe was displaced but uninvolved. Complete surgical resection was done and histopathology revealed psammomatoid bodies diagnostic of juvenile psammomatoid ossifying fibroma (JPOF). JPOF is a rare bone tumour characterised by a predilection for the sino-nasal tract and orbit, a tendency to affect younger patients, a potential for aggressive growth and a high recurrence rate of 30-50%. It warrants a complete surgical resection to avoid recurrence.