A comparative study of smooth muscle cell characteristics and myofibroblasts in processus vaginalis of pediatric inguinal hernia, hydrocele and undescended testis.

BACKGROUND: Congenital inguinal hernia, hydrocele and undescended testis (UDT) are associated with patent processus vaginalis. The smooth muscles present in the processus vaginalis aid in the descent of the testis and undergo programmed cell death after testicular descent leading to obliteration. The persisting amount of smooth muscle in the processus vaginalis influences the clinical outcome as inguinal hernia, hydrocele or UDT. Therefore, a study was conducted to evaluate the processus vaginalis in these three conditions to observe the presence and phenotype of smooth muscle cells and the presence of myofibroblasts. MATERIALS AND METHODS: The processus vaginalis sacs in patients with inguinal hernia, hydrocele and UDT were examined using light microscopy for the presence and distribution of smooth muscle cells and immunohistochemical staining for vimentin, desmin, and α-smooth muscle actin (SMA) to identify the smooth muscle phenotype. Transmission electron microscopy was also performed in all the sacs to observe the presence of myofibroblasts. RESULTS: Seventy-eight specimens of processus vaginalis (from seventy-four patients), distributed as 47%, 27%, and 26% as inguinal hernia, hydrocele and UDT respectively, were included in the study. The sacs from inguinal hernia and hydrocele had significantly more presence of smooth muscles distributed as multiple smooth muscle bundles (p < 0.001). Desmin and SMA staining of smooth muscle cells was observed in significantly more sacs from hydrocele, followed by inguinal hernia and UDT (p < 0.001). The sacs from UDT had a significant presence of striated muscles (p = 0.028). The sacs from inguinal hernia had a significant presence of myofibroblasts, followed by hydrocele and UDT (p < 0.001) and this significantly correlated with the light microscopy and immunohistochemical features. The processus vaginalis sacs from four female patients did not differ statistically from the male inguinal hernia sacs in any of the above parameters. CONCLUSION: The processus vaginalis sacs in pediatric inguinal hernia, hydrocele and undescended testis differ in the presence, distribution and phenotype of smooth muscles and the presence of myofibroblasts. The clinical presentations in these entities reflect these differences.

Dermoscopy of hypopigmented macules unveiling genetic diagnosis of tuberous sclerosis complex type 2 in an infant presenting with sacral chordoma.

A 2-month-old male with surgically resected sacral chordoma presented with multiple hypopigmented macules showing characteristic patchy, sharply demarcated areas of pigment network on dermoscopy. These dermoscopic findings were suggestive of the ash-leaf macules of tuberous sclerosis over other common hypopigmented macules in neonates. Chordomas presenting in early childhood in the sacral location have been reported as a rare manifestation of tuberous sclerosis complex. The combination of these findings led to a diagnosis of tuberous sclerosis, confirmed with the finding of a heterozygous TSC2 gene deletion; treatment with sirolimus resulted in regression of cardiac rhabdomyomas and hypopigmented macules.

Comparison of Ultrasound Examination and Fiberoptic Laryngoscopy for Confirmation of Laryngeal Mask Airway Placement.

OBJECTIVES: 1) To compare ultrasound (US) examination and fiberoptic laryngoscopy (FOL) for confirmation of laryngeal mask airway (LMA) placement. 2) To evaluate the necessity for reinsertion of LMA based on FOL. METHODS: This prospective observational study included 100 adult patients of American Society of Anesthesiologists (ASA) Grade I and II, undergoing elective surgery under General Anesthesia requiring Proseal LMA™ placement as an airway device. LMA placement was first confirmed by clinical tests. Clinically acceptable patients were further assessed by US and categorized as acceptable (US-A) or unacceptable (US-U) and again by FOL as (FOL-A and FOL-U). Categorical variables presented in number, percentage (%), and continuous variables presented as mean ± SD and median. Inter-rater kappa agreement was used to find out the strength of agreement of acceptability between FOL and US. RESULTS: The LMA placement was clinically acceptable in 82% of patients on first attempt. FOL had 63% (FOL-A) acceptable LMA placement as compared with US examination which had 56% (US-A). In 85% of patients, US and FOL findings were in good agreement with each other for LMA placement (κ = 0.690 and P < .05). In all patients of FOL of unacceptable (FOL-U) category (37%), LMA was replaced with endotracheal tube. CONCLUSION: US provides a safe, non-invasive, and real-time dynamic assessment with 85% diagnostic accuracy for confirmation of LMA placement as compared with FOL.

Pediatric Primary Yolk Sac Tumour of the Kidney: Recommendations for Pretreatment Diagnosis.

Introduction Although nephroblastomas are frequently treated without prior biopsy, there are the occasional other pediatric renal tumors that require different management. In the literature, there are around 30 primary renal germ cell tumors (GCT), including four cases of Yolk sac tumor (YST). We present another primary renal YST.Case report: A five-year-old boy was diagnosed as Wilms tumor on radiology and needle biopsy. He received chemotherapy, with no response. The post-chemotherapy resection specimen revealed a YST.Conclusion: Renal YST may be indistinguishable from Wilms tumor clinically and radiologically. For pre-biopsy chemotherapy management protocols, serum tumor markers such as AFP may be recommended to identify the occasional GCT, including YST. Pre-chemotherapy needle biopsies may lead to misdiagnosis, and may require confirmation by an experienced pathologist or central review.

Histopathological, Ultrastructural, and Immunohistochemical Findings in Radial Longitudinal Deficiency: A Prospective, Observational Study.

PURPOSE: To report the histopathological, electron microscopic, and immunohistochemical findings of tissue samples obtained from patients with radial longitudinal deficiency (RLD) and investigate the contribution of abnormality in soft tissues as a secondary driver of deformity in RLD. METHODS: Specimens from radial-sided muscles and tendons were obtained at the time of surgery (either radialization or centralization) from 14 patients with 16 limbs affected with Bayne type 3 and type 4 RLD. The specimens were evaluated using light microscopy, electron microscopy, and immunohistochemical examination. RESULTS: Among the 16 frozen muscle specimens, 6 (37%) showed normal muscle, while 10 (63%) showed the presence of atrophic fibers. The 6 cases with normal muscle showed no abnormality in fiber type distribution. Six patients showed predominance of type 1 muscle fibers. None of the specimens had myofibroblasts; 4 of 16 specimens had mast cells, and 9 of 16 specimens showed the presence of platelet derived growth factor-positive cells. Features of myofibroblasts (the presence of basal lamina, intercellular junctions, or pinocytic vesicles) were not identified in any specimen on electron microscopy. CONCLUSIONS: The histopathological, electron microscopic, and immunohistochemical findings, in particular the absence of myofibroblasts, in tissue samples obtained from patients with RLD, do not support the assumption of abnormality in soft tissues as a secondary driver of deformity in RLD. CLINICAL RELEVANCE: This study provides a preliminary insight into a possible role of soft tissues in the development of the deformity in RLD.

Acinar Cell Carcinoma of the Uncinate Process of the Pancreas in a Child Managed Sans Whipple's Procedure-a Rare Case Scenario.

Acinar cell carcinoma (ACC) is a rare malignant tumor of the pancreas. A 10-year-old girl presented with a large tumor arising from the pancreatic head. Excision sans Whipple's procedure was performed. Histopathology revealed it as ACC. In the context of this case, this rare tumor is being reported to highlight that such tumors arising from the head of the pancreas can be managed successfully without always resorting to a Whipple's procedure.

Utility of the Milan system for reporting salivary gland cytopathology during rapid on-site evaluation (ROSE) of salivary gland aspirates.

OBJECTIVE: Rapid on-site evaluation (ROSE) is a fine needle aspiration (FNA) technique for ensuring sampling adequacy and triaging samples. The Milan system for reporting salivary gland cytopathology (MSRSGC) is a standardised reporting system which aims to improve risk stratification. There is scant literature on the diagnostic value and agreement of MSRSGC on ROSE with final cytological diagnosis in salivary gland FNAs. We aimed to assess the concordance of MSRSCG categorisation and diagnosis on ROSE with final cytological and histological diagnosis. METHODS: This prospective study included consecutive salivary gland FNAs for which ROSE was performed over a six-month period. MSRSGC category and diagnosis on ROSE were compared with the final cytological diagnosis and MSRSGC category, and histopathological diagnosis, where available. RESULTS: Sixty salivary gland aspirates were included. The adequacy rate with ROSE was 100%. Using the MSRSGC classification during ROSE, 26 (43.2%) samples were categorised as benign neoplasm, 21 (35%) as malignant neoplasm, 9 (15%) as non-neoplastic, and one each (1.7%) belonged to the remaining four categories. MSRSGC categorisation on ROSE concurred with final the cytological diagnosis in 58/60 cases (96.7%). Discrepancies in MSRSGC categories on ROSE included one atypia of undetermined significance with final report as non-neoplastic, and one non-diagnostic as suspicious for malignancy. Good correlation of MSRSGC categories on ROSE with final histopathological diagnosis (88.9% concordance) was also noted. CONCLUSIONS: MSRSGC on ROSE shows good concordance with final cytology and histopathology diagnosis, indicating that categorisation according to MSRSGC has utility in ensuring that adequate material is obtained and triaged appropriately for the diagnosis of salivary gland aspirates.

Tumor-host interface in oral squamous cell carcinoma: Impact on nodal metastasis and prognosis.

PURPOSE: To evaluate tumor-host interface in oral squamous cell carcinoma (OSCC) by the Brandwein-Gensler histological risk score (BG risk score); to assess its association with clinicopathological features and impact on survival outcomes in a contemporary cohort staged as per AJCC 8th edition pTNM classification. METHODS: This retrospective cohort study at a tertiary care centre included 178 cases of OSCC treated by primary surgical resection from 2013 to 2016. Pathological lymph node status, disease-free survival (DFS), overall survival (OS) were assessed. RESULTS: BG risk score assessment categorized 25 (14%) cases as low-risk, 93 (52%) as intermediate-risk, and 60 (34%) as high-risk. BG risk score category progression from low to intermediate to high risk was associated with an incremental risk of worsening pN status, DFS, and OS. BG risk score categories significantly demarcated 2-year DFS (96% in low-risk, 51.6% in intermediate-risk, 15% in high-risk; p < 0.001) and OS (96% in low-risk, 66.7% in intermediate-risk, 31.3% in high-risk; p < 0.001). On stratified analysis, BG risk score could further demarcate prognosis in early (I/II) and late (III/IV) stage subgroups (p < 0.001). Multivariate analysis indicated the prognostic impact of BG risk score categories to be additional to, and of equal magnitude to, impact of pTNM stage. CONCLUSIONS: BG risk score is a powerful prognostic tool in OSCC additional to pTNM staging. It can enable risk stratification and inform decisions regarding post-surgical adjuvant treatment. It is undertaken with routine histopathological evaluation, with no increased expense or turnaround time. A case is made for its inclusion in OSCC reporting guidelines.

Is the retropharyngeal lymph node the first echelon node for carcinoma tonsil? Prospective evaluation and literature review.

PURPOSE: Tonsil cancer being predominantly treated by non-surgical means, there is a paucity of data on lymph nodal drainage pathways and histo-pathologically confirmed metastatic rates. This study assesses the retropharyngeal lymph node (RPLN) in N0 squamous cell carcinoma tonsil as a possible first echelon node and a site for occult metastasis. METHODS: Prospective study involving treatment naïve N0 carcinoma tonsil treated by primary surgery and adjuvant treatment from June 2017 to March 2019. In-vivo lymph nodal drainage patterns were assessed by sentinel node mapping by preoperative SPECT-CT and intra-operative hand-held Gamma probe. All patients had a subsequent Level I-III/IV sampling neck dissection supplemented with RPLN dissection. Histological evaluation of sentinel nodes and RPLN involved step-serial sectioning and pan-cytokeratin immunohistochemistry. A comprehensive literature review was performed with keywords "retropharyngeal lymph node", "oropharynx", "tonsil", "squamous cell carcinoma" to determine the incidence of RPLN positivity in previously published series. RESULTS: Sentinel node was successfully identified by SPECT-CT in all 17 patients (ipsilateral level 2a-13/17, 2b-1/17, 3-1/17; bilateral 2a-1/17; isolated contralateral retropharyngeal node-1/17). 8/17 had occult neck metastasis. In no patient was an ipsilateral RPLN identified as the sentinel node. Histological sampling did not indicate metastatic tumor in the RPLN in any patient (0/17). A systematic literature review further confirmed that RPLN metastasis in oropharyngeal cancer is noted only in the presence of pN + disease at other neck levels, and isolated RPLN metastasis is extremely rare (1.2%). CONCLUSION: The ipsilateral RPLN is not identified either as the first echelon node or as a site of occult metastatic disease in N0 tonsil cancer. CTRI REGISTRATION: CTRI/2019/06/019551.

Sinonasal IgG4-related disease: a rare and emerging entity broadening the differential diagnosis in the sinonasal universe.

BACKGROUND: IgG4-related disease (IgG4-RD) is a multi-organ immune-mediated disorder characterized by fibroinflammatory mass-forming lesions, mimicking malignancy or infection. While well-documented in salivary glands, orbit and thyroid in the head and neck, sinonasal IgG4-RD is rare. METHODS: Cases of sinonasal IgG4-RD were retrieved, and clinicopathological features reviewed. RESULTS: Seven cases of sinonasal IgG4-RD were identified over a 2-year period, including three males and four females, with an age range of 13-48 years (median: 32 years). Patients presented with cheek swelling, pain and visual disturbances. Serum IgG4 levels were mildly elevated. Storiform fibrosis, obliterative phlebitis and plasma cell infiltration were seen in varying proportions. Destruction of bone and subepithelial mucoserous glands was present. ALK-1 negativity distinguished from inflammatory myofibroblastic tumor. CONCLUSION: Sinonasal IgG4-RD expands the growing spectrum of IgG4-RD. A high degree of suspicion is required to include IgG4-RD in differential diagnosis of sinonasal masses, and perform detailed histological and immunohistochemical workup for accurate diagnosis.

Anaplastic large cell lymphoma presenting as an endobronchial mass with lung involvement in an adolescent boy.

Primary endobronchial presentation of anaplastic large cell lymphoma is rare in the paediatric age group. We present a 12-year-old boy with breathlessness, fever, cough and weight loss, who was misdiagnosed as a case of tuberculosis and started on antitubercular therapy, which showed no improvement. Chest X-ray showed a completely opacified left hemithorax and chest computed tomography revealed a mass encircling the left main bronchus with collapse- consolidation of the left lung. Fibreoptic bronchoscopy revealed a growth in the left main bronchus. Subsequently, fine-needle aspiration cytology and biopsy from the mass confirmed it to be a malignancy consistent with anaplastic large cell lymphoma. Metastatic work-up revealed no other sites of involvement. Chemotherapy resulted in rapid and complete regression of the tumour. No evidence of local or distant recurrence was reported after 18 months of follow-up. Clinicians and pathologists should be aware of this presentation as prompt diagnosis and treatment can give promising results. This case highlights the importance of timely tissue diagnosis in patients with non-resolving pyrexia and organ lesions on imaging.

p16 Immunoexpression in sinonasal and nasopharyngeal adenoid cystic carcinomas: a potential pitfall in ruling out HPV-related multiphenotypic sinonasal carcinoma.

AIMS: Adenoid cystic carcinoma (AdCC) is frequent in the sinonasal region. The recently described human papilloma virus (HPV)-related multiphenotypic sinonasal carcinoma (HMSC) histopathologically resembles solid AdCC, but has a better outcome. Thus, clinical and pathogenetic differences between HMSC and sinonasal AdCC necessitate their distinction. We conducted this study to assess p16 immunoexpression in previously diagnosed AdCC cases, and to identify HMSC cases in p16 immunopositive cases. METHODS AND RESULTS: Cases diagnosed as sinonasal and nasopharyngeal AdCC were retrieved. Histomorphological features were reviewed. Immunohistochemistry (IHC) for p16 was performed. HPV testing was performed in p16-positive cases by mRNA in-situ hybridisation (mRNA ISH) and polymerase chain reaction (PCR) assay. MYB rearrangement was assessed by fluorescence in-situ hybridisation. One hundred and two AdCC cases were retrieved. Six cases (5.9%) showed diffuse p16 positivity. HPV mRNA ISH and PCR were negative in p16-positive cases. Two cases showed MYB rearrangement. p16-positive cases were composed of basaloid cells demonstrating a cribriform pattern, at least focally. The predominant pattern was cribriform in three and solid in three cases. One case showed two distinct components: keratinising squamous cell carcinoma and cribriform AdCC. Other morphological patterns seen were tubular, reticular, epithelial-myoepithelial carcinoma-like, and glomeruloid, forming a minor component of the tumour area. CONCLUSIONS: p16 staining alone, even when diffuse and strong, cannot be used as a surrogate for HPV testing to distinguish sinonasal AdCC from HMSC. p16 IHC should be accompanied by more specific methods, such as mRNA ISH, so as not to erroneously diagnose HMSC over sinonasal AdCC, bearing in mind the highly aggressive nature of the latter.

Sinonasal amelanotic melanoma with neuroendocrine differentiation: a diagnostic conundrum.

Mucosal malignant melanoma of the head and neck (HN) is a rare and aggressive neoplasm which constitutes only 1% of all melanomas. Neuroendocrine differentiation is an extremely unusual phenomenon in mucosal melanomas, of which five cases have been reported. We report a rare case of a 63-year-old female who developed sinonasal amelanotic melanoma with immunohistochemical expression of neuroendocrine markers, presenting a diagnostic dilemma. Ultrastructural evidence of melanosomes and neurosecretory granules aided in arriving at the diagnosis. Aberrant immunoexpression of neuroendocrine markers, particularly in an amelanotic melanoma, has critical diagnostic implications, as various malignancies with undifferentiated histomorphology occur at this site, many of which stain positively with neuroendocrine markers. We discuss the differential diagnoses and recommend a high index of suspicion so as not to miss the diagnosis of mucosal melanoma at this location.

mTOR pathway activation in focal cortical dysplasia.

BACKGROUND: Focal cortical dysplasia (FCD) is a localized cortical malformation and considerable morphological overlap exists between FCD IIB and neurological lesions associated with Tuberous sclerosis complex (TSC). Abnormal mTOR pathway secondary to somatic mTOR mutation and TSC gene mutation linked to PI3K/AKT/mTOR pathway have supported the hypothesis of common pathogenesis involved. Role of converging pathway, viz. Wnt/ß-Catenin and mTOR is unknown in FCD. We aimed to analyse FCD IIB for TSC1/TSC2 mutations, immunoreactivity of hamartin, tuberin, mTOR and Wnt signalling cascades, and stem cell markers. MATERIALS AND METHODS: Sixteen FCD IIB cases were retrieved along with 16 FCD IIA cases for comparison. Immunohistochemistry was performed for tuberin, hamartin, mTOR pathway markers, markers of stem cell phenotype, and Wnt pathway markers. Mutation analysis for TSC1 and TSC2 was performed by sequencing in 9 FCD cases. RESULTS: All FCD cases showed preserved hamartin and tuberin immunoreactivity. Aberrant immunoreactivity of phospho-P70S6 kinase, S6 ribosomal, phospho-S6 ribosomal and Stat3 was noted in FCD IIB, with variable phospho-4E-BP1 (45%) and absent phospho-Stat3 expression. Immunoreactivity for phospho-P70S6 kinase (100%), S6 ribosomal protein (100%) and Stat3 (100%) was noted in FCD IIA, but not for phospho-S6 ribosomal, phospho-4E-BP1 and phospho-Stat3. c-Myc immunoreactivity was noted in all FCD cases. Nestin (81%) and Sox 2 (88%) stained balloon cells in FCD IIB (44%), while in FCD IIA cases were negative. All FCD cases were immunopositive for Wnt, but were negative for ß-Catenin and cyclin-D1. TSC mutations were detected in two cases of FCD IIB. CONCLUSION: Abnormal mTOR pathway activation exists in FCD IIB and IIA, however, shows differential immunoreactivity profile, indicating varying degrees of dysregulation. Labelling of neuronal stem cell markers in balloon cells suggests they are phenotypically immature. TSC1/2 mutation play role in the pathogenesis of FCD. Deep targeted sequencing is preferred diagnostic technique since conventional sanger sequencing often fails to detect low-allele frequency variants involved in mTOR/TSC pathway genes, commonly found in FCD.

Gastric Adenomyosis: A Rare Cause of Pyloric Mass in Children.

Adenomyoma of the stomach is a benign tumor with a very low incidence. Clinical presentation and imaging modalities are usually nonspecific and variable. A rare case of gastric adenomyoma in a 12-year-old child is being reported who presented with gastric outlet obstruction. The diagnosis could only be established after an excision biopsy performed after multiple diagnostic modalities failed to clinch the diagnosis. The case is being reported in view of the rarity of this entity in the pediatric age group as a cause of gastric outlet obstruction.

Endobronchial ultrasound-guided transbronchial needle aspiration cytology in patients with known or suspected extra-pulmonary malignancies: A cytopathology-based study.

BACKGROUND: Endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) is the primary modality for mediastinal lymph node staging in lung carcinoma. We aimed to evaluate its utility in extra-pulmonary malignancies (EPM). METHODS: Database search of EBUS-TBNA aspirations (2013-2017) done in patients with known/suspected EPMs and mediastinal lymphadenopathy/masses was performed. All archived cytology/histology material was reviewed and categorised as positive, negative and unsatisfactory. RESULTS: The selected 139 patients included 100 patients with known EPMs, 11 patients with known lymphoma, and 28 patients with suspected EPM of unknown primary. EBUS-TBNA was adequate in 110 patients (79%), including 21 patients who yielded only reactive lymphoid tissue. Satisfactory blood clot cores were obtained in 34 patients and contributed significantly to diagnosis and ancillary testing. Metastasis was detected in 45 patients with known EPM, predominantly originating from a known primary in the breast in females (56%) and squamous cell carcinomas of head and neck in males (60%). Granulomatous lymphadenopathy was identified in 16 patients with known EPM (16%). Lymphoma relapse and granulomatous lymphadenopathy were identified in three and four patients with known lymphoma, respectively. In patients with suspected EPM of unknown primary site, malignancy was confirmed in 21 patients, predominantly representing metastatic adenocarcinomas (n = 5) and neuroendocrine neoplasms (n = 5). Immunocytochemistry was performed in 16 of these cases and aided in characterisation of primary site/type of tumour in 12 cases. CONCLUSION: EBUS-TBNA is efficient for screening mediastinal lymph nodes/masses for malignancy in EPMs. Procuring sufficient material for ancillary testing would improve diagnostic accuracy and reduce need for resampling.

Spectrum of cytomorphological features of extranodal NK/T-cell lymphoma, nasal type.

OBJECTIVE: Extranodal natural killer/T-cell lymphoma, nasal type (ENKTL) is an aggressive extranodal lymphoma of NK-cell or T-cell lineage. Its clinical features overlap with those of several sinonasal mass lesions. While the histopathological features are well described, diagnosis is often difficult, owing to presence of extensive coagulative necrosis, so that repeated biopsies may sometimes be necessary for correct diagnosis. Literature on cytological findings of ENKTL is limited. METHODS: Cytomorphological features of cases of histologically confirmed ENKTL having corresponding cytology samples were reviewed retrospectively, to identify distinctive features that could possibly suggest this entity. RESULTS: Aspirates from five patients were studied: four from cervical nodes, one from cheek swelling and one from pleural fluid. Two aspirates were reported as positive for malignancy, two as atypical lymphoid proliferation and one was non-diagnostic. Pleural fluid was reported as malignant, favouring a diagnosis of carcinoma. On cytology, aspirates showed medium to large cells with folded, indented nuclei and abundant pale cytoplasm, some with tongue-like cytoplasmic protrusions. A distinctive feature was presence of large loose clusters of tumour cells with arborising capillaries running through them. Interestingly, necrosis was consistently absent. Subsequent biopsies from palate (three cases) and nasal masses (two cases) confirmed the diagnosis of ENKTL. CONCLUSIONS: Suspicion of ENKTL on cytology is crucial for timely diagnosis to avoid diagnostic delay, especially when only highly necrotic biopsy samples are available. Awareness of distinctive cytomorphological features is required to make fine needle aspiration an effective diagnostic tool for initial diagnosis and for evaluation of possible recurrences.

BK polyomavirus and urothelial carcinoma: Experience at a tertiary care centre in India with review of literature.

INTRODUCTION: BK polyomavirus is ubiquitous and remains dormant in the urothelial tract, reactivating and replicating in the immunocompromised state especially in the setting of post-renal transplantation where it is believed to be directly oncogenic based on recent reports. Its oncogenic role in the immunocompetent host is controversial. This study aimed to investigate the association of BK polyomavirus in Urothelial Carcinoma. MATERIAL AND METHODS: Patients with suspected urothelial carcinoma (UC) admitted under Department of Urology over a period of one year were recruited and transuretheral bladder tumor (TURBT) resection was performed, along with sampling of cystoscopically normal-appearing urothelium away from the tumor. In addition, cystectomy specimens with UC were included, with sampling of grossly normal-appearing urothelium away from the tumor. Immunohistochemistry (IHC) for SV40 T-Antigen and chromogenic in situ hybridization (CISH) using BK polyomavirus specific probe was performed on the paired samples (tumor and normal). RESULTS: Twenty-three TURBT and 14 cystectomy specimens were assessed. None of the cases showed evidence of BK polyomavirus infection in tumor or in surrounding mucosa by IHC. CISH performed in ten cases were also found to be negative. In comparison, one post-renal transplant urothelial carcinoma in our experience showed diffuse SV40 staining. CONCLUSIONS: This study suggests that BK polyomavirus infection is not associated with urothelial malignancy in the immunocompetent setting unlike in the immunocompromised setting where it should always be investigated for.

Pompe disease: An Indian series diagnosed on muscle biopsy by ultrastructural characterization.

Pompe disease (PD) is a lysosomal storage disorder characterized by glycogen accumulation in muscle, with infantile-onset (IOPD) and late-onset (LOPD) types. Nineteen cases of PD were diagnosed over a 14-year period on muscle biopsy by ultrastructural examination. Pools of glycogen (intralysosomal and cytoplasmic) and excessive phagocytosis were seen in myofibers on electron microscopy. Glycogen was noted in endothelial cells in IOPD. Although PD accounts for a small fraction of muscle diseases, timely accurate diagnosis is imperative as it is treatable. Ultrastructural examination is necessary to confirm the diagnosis in cases with non-diagnostic light microscopic features, especially in adult LOPD patients.