Trichilemmal carcinoma metastatic to parotid gland: First report of fine needle aspiration cytology features

Trichilemmal carcinoma is a rare malignant cutaneous adnexal neoplasm arising from the outer root sheath of the hair follicle. Majority of cases occur on sun-exposed sites such as the face, scalp and neck, making them easily amenable to being biopsied and subjected to histological examination for definitive diagnosis. Thus, cytological features of trichilemmal carcinoma have not been described till date. Trichilemmal carcinoma is a low-grade malignancy, albeit with potential to metastasize to regional lymph nodes and distant sites. We report the case of trichilemmal carcinoma of scalp that metastasized to cervical lymph nodes and parotid gland and underwent fine-needle aspiration cytology (FNAC) from the parotid lesion. The aspirate showed tightly cohesive cell clusters with sharp borders. Tumour cells ranged from basaloid with scant cytoplasm to those with abundant cytoplasm. Nuclei were vesicular, with inconspicuous to prominent nuclei. Intercellular bridges, masses of keratin, and fragments of desmoplastic stroma were present, closely recapitulating histological features of trichilemmal carcinoma, which enabled diagnosis as metastasis. Cell block showed similar tumour fragments with evidence of differentiation towards outer root sheath. FNAC is the first-line investigation to obtain a tissue diagnosis of masses in the head and neck region. Although rarely encountered, the lack of knowledge of cytological features of trichilemmal carcinoma may hamper its FNAC diagnosis at metastatic sites. When intraparotid metastases occur, they may be mistaken as primary salivary gland carcinoma. Thus, awareness of the cytological features of this tumour must be raised among cytopathologists to enable accurate diagnosis and further management.

Assessment of MUC5AC and MUC2 Immunoexpression in Glandular Odontogenic Cysts, Dentigerous Cysts, and Mucoepidermoid Carcinomas

Glandular odontogenic cysts (GOCs) and dentigerous cysts may show mucous metaplasia. Central mucoepidermoid carcinoma is very rare and mostly associated with dental cysts. It is hypothesized that odontogenic cysts showing mucus differentiation in their lining, have a propensity to transform into MEC. The present study is the first attempt to explore the relationship between odontogenic cysts [GOCs and dentigerous cysts with mucus metaplasia (DCMM)] and MEC by evaluating immunoexpression of MUC5AC and MUC2. Immunoexpression of MUC5AC and MUC2 was evaluated semiquantitatively in GOCs (20 cases), DCMMs (20 cases), and MECs (20 cases). The percentage of positive cells, intensity, and localization of immunoexpression were assessed for each marker in all cases. Of GOCs, DCMMs, and MECs cases, 85%, 70%, and 80%, respectively, were immunopositive for MUC5AC. Strong cytoplasmic immunoreactivity for MUC5AC was noted, particularly in mucous cells present diffusely within MECs. However, the immunoreactivity was limited to the epithelial lining of GOCs and DCMMs. Most of the MECs (60%) showed more than 25% positivity for MUC5AC, followed by GOCs, and the least in DMMCs. Mild cytoplasmic and nuclear positivity of MUC2 was noted only in epithelial lining cells of 70% GOCs and 45% DCMMs. Whereas, 55% of MECs displayed moderate to strong cytoplasmic and membranous immunopositivity for MUC2 exclusively within mucous cells. As MECs showed strong MUC5AC immunoreactivity in mucous cells, immunoexpression of MUC5AC in odontogenic cysts with mucus cells can possibly explain the pathogenesis of MEC from cysts. However, the variable expression of MUC2 did not give any strong evidence regarding its role as a marker.

Role of CD34-immunopositive Microvascular Density in Juvenile Nasopharyngeal Angiofibroma

Objective

To assess the microvascular density (MVD) in juvenile nasopharyngeal angiofibroma (JNA) with CD34 immunostaining and evaluate its relationship with clinico-demographic features.

Methods

This prospective study included patients with JNA undergoing endoscopic excision. The histopathological specimen was stained using CD-34 antibodies to calculate MVD. MVD and clinico-demographic features were correlated.

Results

The study included 12 patients with a median age of 15.5 years. The mean MVD was 39 vessels/high power field (range 5 to 151 vessels). MVD was significantly associated only with the volume of tumour (r = 0.65, p = 0.02). The recurrence occurred in one patient with an MVD of 107. The median follow-up was 38 months.

Conclusion

MVD is significantly associated with tumour volume in JNA, which implies a robust role of angiogenesis in the pathology of the tumour. Also, higher MVD may be a risk factor for recurrence.

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.

Clinico-pathological Factors in Malignant Transformation of RRP

Various clinico-pathological factors play role in the papilloma proliferation and pathogenesis of Recurrent respiratory papillomatosis (RRP). However, it is not known if they are directly responsible for malignant transformation of these papillomas or not. We did this study to elucidate any such association. The most recent debrided tissue of RRP in 20 patients was evaluated for p16 expression, VEGF estimation (tissue expression and serum levels), and tissue HPV DNA concentration. The final histopathology results were then correlated with these pathological factors and with clinical factors like duration of illness, age of onset of symptoms, extent of disease, etc. Squamous papilloma was seen in 60%, dysplasia in 25%, and squamous cell carcinoma (SCC) in 15% of the patients. Positive immunostaining for p16 (staining in ≥70% of tumor cells) was seen only in one case, which was SCC. There was no statistically significant difference between p16 expression, tissue VEGF expression, serum VEGF levels, and tissue HPV DNA in any of the histological groups. The mean age of disease onset was significantly higher in patients with SCC (p = 0.03). A significantly higher number of patients with dysplasia had tracheobronchial involvement (p = 0.022). We concluded that no single pathological factor is solely responsible for development of malignancy in RRP, whereas clinical factors like tracheobronchial involvement and age of onset may contribute to development of dysplasia or carcinoma.

Myeloblastic meningeal neoplasm: an unusual natural history

Myeloid sarcoma is a very rare extramedullary malignant tumour, most often associated with acute myeloid leukaemia. We report the case of a man in his early 20s who presented with chronic headache, raised intracranial pressure and progressive vision loss of 2 years duration with no systemic manifestations. He had a history of myeloid sarcoma of the left thigh 15 years ago, treated with external beam radiotherapy and in complete remission for more than 13 years. However, the progressive blindness remained unexplained for 2 years, and he was eventually diagnosed with isolated meningeal relapse without marrow or systemic involvement. Imaging revealed subarachnoid haemorrhage, diffuse leptomeningeal enhancement and involvement of lower dorsal cord and conus, and cerebrospinal fluid cytology showed myeloid blasts. He was managed with intrathecal chemotherapy and craniospinal irradiation, after which he had mild improvement in vision.

HPV-Associated Squamous Cell Carcinoma of the Eyelid: Diagnostic Utility of p16 Immunohistochemistry and mRNA In Situ Hybridization

BACKGROUND

High-risk (HR) Human papillomavirus (HPV) has been implicated in pathogenesis of squamous cell carcinomas (SCC) at several sites with mucocutaneous junctions, including the head and neck. SCC is the second most common eyelid malignancy. However, its association with transcriptionally active HR-HPV has not been adequately studied.

METHODS

Two index cases of eyelid HPV-associated SCC are described in detail. A retrospective cohort of eyelid SCC was examined for p16 immunoexpression. Cases demonstrating p16 positivity or equivocal staining were subjected to high-risk HPV mRNA in situ hybridization (ISH). Quantitative real-time PCR (qPCR) was performed in mRNA ISH-positive cases for HPV genotyping.

RESULTS

The two index patients were older adult females, with upper eyelid tumours. On histology, both tumours were non-keratinizing SCC with trabecular and nested architecture reminiscent of oropharyngeal HPV-associated non-keratinizing SCC, prompting p16 immunohistochemistry, which was positive. HR-HPV mRNA ISH was positive, and qPCR detected HPV16 in both cases. Three of 20 (15%) archival cases showed p16 immunopositivity and two (10%) showed equivocal staining. However, mRNA ISH was negative. All cases showing p16 immunostaining and lacking HR-HPV were keratinizing SCCs. Thus, 9% of all eyelid SCC examined demonstrated HR-HPV.

CONCLUSION

The prevalence of HR-HPV in eyelid SCC is low in Indian patients. HPV-associated SCC may mimic commoner eyelid carcinomas as it lacks overt keratinization. In basaloid-appearing eyelid carcinomas, p16 immunopositivity should be followed by reflex HR-HPV mRNA ISH, as p16 immunohistochemistry alone has low specificity. The prognostic role, if any, of HPV association needs further evaluation.

Primary intradural extramedullary lesions: a longitudinal study of 212 patients and analysis of predictors of functional outcome

BACKGROUND

Primary intradural extramedullary (IDEM) lesions are rare, with an incidence of about 1/100,000 person-years. The aim of this study was to investigate their demographic, clinical, imaging, management, histopathological and outcome parameters. Another objective was to evaluate the various predicting factors leading to long-term favorable outcomes, thereby answering the controversial question: when to operate?

METHODS

This study observed 212 patients of primary IDEM lesions and followed-up for a mean of 53.80 months. The patient's outcome using McCormick grade at follow-up was correlated with age, sex, duration of symptoms, preoperative McCormick grade, tumor location and extent, extradural spread, extent of excision, vascularity, WHO grade and histopathological tumor type.

RESULTS

Benign nerve sheath tumors were the commonest lesions (47.17% schwannoma, 4.72% Neurofibroma), followed in incidence by meningioma (19.34%). There was predominance of males (57.08%), except in meningiomas (male: female ratio 1:2.15). Pain was the commonest initial symptom (51.88%). Limb weakness was the most common presenting complaint (88.68%). Gross total excision was achieved in 81.60% of cases and 70.75% of patients improved following surgery. The significant factors predicting favorable outcome included preoperative McCormick grade (P=0.001), the vertical extent of the tumor (P=0.027), histopathological tumor type (P=0.023) and WHO grading (P=0.015); and extent of excision had an odds ratio of 1: 2.5.

CONCLUSIONS

Significant predictors of functional outcome following surgery in IDEM lesions included preoperative McCormick grade, extent of the tumor, tumor type, WHO grading and extent of resection. The authors recommend surgery with the intent of complete tumor excision, before the onset of substantial symptoms, for better outcome.

Relevance of Partial p16 Immunostaining in Oral Squamous Cell Carcinoma and Co- Relation with HPV DNA Status

INTRODUCTION

Immunostaining criteria for p16 positivity in oropharyngeal squamous cell carcinoma have been laid down by College of American Pathologists (CAP) and the American Society of Clinical Oncology (ASCO). The staining should be of moderate to strong intensity seen in 70 percent of the tumor cells. Recent studies have pointed out that a small minority of cases are missed using p16 as the surrogate marker at above mentioned cut off. By convention the same criteria have been used for oral squamous cell carcinoma.

MATERIAL AND METHODS

The authors revisited the results of their previous study where immunohistochemistry for p16 was found to be positive by AJCC criteria in 139 out of 800 cases of oral squamous cell carcinoma. For this study, all the p16 immunonegative cases (by AJCC criteria) were analysed again for partial staining patterns, defined for this study as cases with 50-75% cells showing 2+/3+ intensity of nuclear p16 immunostaining and for basal predominant pattern of immunostaining. These cases were subjected to HPV DNA PCR.

RESULTS

Out of the 661/800 cases found to be negative for p16 immunohistochemistry, a total of 34/800(4.25%) showed partial staining based on the criterion of 50-75% cells showing p16 immunostaining intensity of 2/3+.The basal predominant pattern of immunostaining for p16 was seen in 43/800 (5.38%) cases. When these cases were subjected to HPV DNA analysis, 11/34 (32.35%) of the cases showing partial staining and 02/43 (4.7%) of the cases showing basal predominant pattern of p16 immunostaining were found to be HPV-DNA positive.

CONCLUSION

The inclusion of partial immunostaining patterns of p16 in HPV analysis of oral squamous cell carcinoma can improve our understanding of HPV driven oral squamous cell carcinoma.

Diagnosis of Adenoid Cystic Carcinoma with Striking Tubular Hypereosinophilia by MYB and EWSR1 Breakapart Fluorescence In Situ Hybridization

BACKGROUND

Adenoid cystic carcinoma (AdCC), associated with MYB/MYBL1 gene rearrangements, shows epithelial and basaloid myoepithelial cells arranged in tubular, cribriform and solid patterns. Variations from this classic morphology make diagnosis challenging, necessitating molecular testing. AdCC with striking tubular hypereosinophilia (AdCC-STE) is one such recently described histological subtype.

METHODS

A 52-year-old female presented with a floor of mouth swelling for two months, diagnosed elsewhere as polymorphous adenocarcinoma (PAC). A biopsy was obtained. With a diagnosis of oncocytic neoplasm, wide excision of the tumor was undertaken. Histological examination, fluorescence in situ hybridization (FISH) and ultrastructural examination were performed. Archival cases of PAC and epithelial myoepithelial carcinoma (EMC) were reviewed, and MYB immunostaining and FISH were performed to identify potential AdCC-STE cases.

RESULTS

The excised tumor from the index patient showed bilayered tubules, micropapillae and cribriform pattern. Luminal cells with hypereosinophilic to clear cytoplasm were surrounded by flattened abluminal cells. Focally, basophilic matrix was seen within sharply demarcated pseudocystic spaces. FISH revealed MYB and EWSR1 gene rearrangements, confirmatory of AdCC-STE. Electron microscopy showed features consistent with AdCC; however, mitochondria were not prominent. Among 14 archival PACs, two showed MYB immunopositivity; one showed MYB rearrangement but was classical AdCC. Among 35 EMC, one case showed MYB immunoreactivity and eosinophilia of luminal cells but lacked MYB/MYBL1 rearrangement.

CONCLUSION

Awareness of unusual histological subtypes of AdCC, such as AdCC-STE, is imperative, as it may be misdiagnosed as PAC and EMC, among others. Presence of basophilic matrix and squamoid morules in a biphasic tumor even with hypereosinophilic rather than basaloid myoepithelial appearance should raise suspicion for AdCC-STE, and prompt molecular testing for confirmation. With wider accessibility, lower cost and significantly shorter turn-around-time when compared to RNA sequencing, FISH can be employed for confirmation of diagnosis, especially in low- and middle-income countries.

Comparison of 68Ga-PSMA-HBED-CC and 18F-FDG PET/CT in the Evaluation of Adenoid Cystic Carcinoma-A Prospective Study

PURPOSE OF STUDY

18F-FDG PET/CT plays a major role in diagnosis and staging of head and neck cancer; however, FDG has lower uptake in adenoid cystic carcinoma (AdCC). Prostate-specific membrane antigen (PSMA) expression is found to be associated with endothelial cells or tumor neovasculature in malignant AdCC and salivary duct carcinoma. Thus, present study is aimed to compare the role of 68Ga-PSMA and 18F-FDG PET/CT in patients with primary and/or metastatic AdCC.

MATERIALS AND METHODS

Histopathologically proven AdCC patients were intravenously injected with 370 MBq (10 mCi) of 18F-FDG and 111-185 MBq (3-5 mCi) of 68Ga-PSMA. Images were acquired at 60 and 45 minutes postinjection for 18F-FDG and 68Ga-PSMA, respectively, on dedicated PET/CT scanners. Visual and semiquantitative analyses of PSMA expression in regional and metastatic sites were performed by 2 experienced nuclear medicine physicians.

RESULTS

Seventeen patients (7 men, 10 women) having mean age of 44 ± 14.19 years were prospectively included in the study. Of 17 patients, FDG PET/CT was performed in only 14 (82%) patients. PSMA and FDG uptakes were seen at the primary site in 16 (94%) and 13 (93%) patients, respectively, whereas 1 patient was postradical tumor excision. Lung lesions (n = 7) and lymph nodes (n = 5) were detected on both FDG and PSMA PET scans. However, cerebellar and meningeal metastasis (n = 1, 6%) and bony lesions (n = 2, 12%) were detected only on PSMA PET/CT but not visualized on FDG PET/CT scan.

CONCLUSIONS

PSMA may have theranostic importance in unresectable or metastatic AdCC, besides having a role in staging/restaging.

Liver Metastasis from Nasopharyngeal Carcinoma Diagnosed on Fine Needle Aspiration Cytology

A 12-year-old boy presented with abdominal distention for 1 year. On examination, he had massive hepatomegaly. Facial swelling in the maxillary region, palpable left cervical lymph nodes, and a nasal twang to his voice were detected. Imaging showed multiple hypodense liver lesions, necrotic mediastinal and hilar lymph nodes, multiple lytic-sclerotic skeletal lesions, and lesions in the nasopharynx and maxilla. Fine needle aspirate (FNA) from the cervical lymph node yielded blood. FNA from the liver showed singly dispersed and cohesive clusters of tumor cells, with interspersed neutrophils and tingible body macrophages. Cells had scant to moderate fragile cytoplasm, enlarged vesicular nuclei, and prominent nucleoli. Immunohistochemistry on cell block revealed positivity for cytokeratin and Epstein-Barr virus (EBV)-Latent Membrane Protein-1 (LMP1). A diagnosis of metastatic nasopharyngeal carcinoma was made, and was confirmed on a subsequent biopsy from the femur.

Tumour-infiltrating lymphocyte subsets and their individual prognostic impact in oral squamous cell carcinoma

AIMS

Current understanding of oral squamous cell carcinoma (OSCC) is incomplete with regard to prognostic factors that lead to the considerable heterogeneity in treatment response and patient outcomes. We aimed to evaluate the impact of individual tumour-infiltrating lymphocyte (TIL) subsets on prognosis as a possible rationale for this, in a retrospective observational study.

METHODS

Immunohistochemistry was performed to quantitatively assess cell densities of CD3+, CD20+, CD4+, CD8+ and FOXP3+TIL subsets in 50 surgically treated OSCC cases. Results were correlated with disease-free survival (DFS) and overall survival (OS). Receiver operating characteristic curve analysis and Youden index were applied to determine prognostically significant cut-off values.

RESULTS

Mean counts for CD3+, CD4+, CD8+, CD20+ and FOXP3+TILs were 243, 52, 132, 53 and 116 cells per high power field, respectively. High CD8+ and low FOXP3+TIL counts, and high ratio of CD8:FOXP3 were significantly associated with longer DFS and OS, as well as with improved tumour-host interface parameters.

CONCLUSIONS

Host immune response and its interaction with cancer cells have a significant impact on OSCC outcomes, with some TIL subsets being more clinically relevant than others. High cytotoxic T-cell (CD8) and low Treg (FOXP3) counts, and high cytotoxic T-cell to Treg (CD8:FOXP3) ratio are significantly associated with favourable prognosis. These results may serve as a leading point in identifying novel therapeutic agents that can redesign the tumour immune microenvironment by reducing infiltrating FOXP3-lymphocytes, and modifying their signalling pathways.

Can Superoxide Anions Predict the Malignant Potential of Carotid body Tumor? - A Pilot Study

Currently, there is no consensus on estimating the malignant potential of Carotid Body Tumor (CBT) and the only way to predict a metastatic CBT is through DOTANOC Positron Emission Tomography (PET) scan. There is a well-established correlation between CBT and superoxide anions inside tumor cells. The purpose of this pilot study was to measure superoxide anions inside CBT cells and find if these can be used as marker to predict malignant potential of CBT. The results were also co-related with findings of DOTANOC PET scan retrospectively. The CBT tissue from 10 patients was stained using a fluorogenic dye and superoxide anions were measured by analysis of fluorescent image. The patients were divided into two groups - First group with four patients having potentially malignant CBT based upon clinico-surgical characteristics and second group with the rest of the six patients. It was seen that the superoxide anions were highest in the first group which included patients with metastatic carotid body tumor, patients with multiple paragangliomas and patient with positive family history (p = 0.011). The same patients also had metastasis and multiple tumors detected on DOTANOC PET scan. It was concluded that measuring superoxide anions in excised tumor tissue can be used to estimate malignant potential of CBT and can identify patients who truly require DOTANOC PET scan; without affecting the treatment, as it is an expensive investigation involving ionizing radiation and may not be available in all centres.

Supplementary Information

The online version contains supplementary material available at 10.1007/s12070-023-03623-6.

Evaluation of high-risk human papillomavirus in sinonasal papillomas and squamous cell carcinomas

The sinonasal tract is considered a second hotspot for human papillomavirus (HPV)-related tumors in the head and neck, with HPV being identified in up to 62% of squamous cell carcinomas (SCCs) and 38% of papillomas. There is limited data from geographical regions with low prevalence of high-risk (HR)-HPV on the association of HR-HPV in sinonasal neoplasms and on utility of p16 as a surrogate marker. p16 immunohistochemistry, HR-HPV mRNA ISH and quantitative real-time PCR (qPCR) were performed on a retrospective cohort of sinonasal papillomas and SCCs. KRAS mutation analysis was done in oncocytic papillomas. p16 positivity was present in 22/142 cases (15.5%) including eight inverted papillomas, one oncocytic papilloma (OP), and 13 SCC. Among these, mRNA ISH showed HR-HPV in the OP and two SCC, while another SCC was found to harbour HPV18 by qPCR. Two HPV-associated SCCs had foci of OP. mRNA ISH was negative in all p16 negative cases. p16 immunohistochemistry showed 68% concordance with mRNA ISH, and had sensitivity and negative predictive value of 100%; specificity was 67%, and positive predictive value was 14.3%. Association with HR-HPV in sinonasal papillomas and SCC is rare, and may be seen in cases demonstrating oncocytic morphology. p16 immunohistochemistry has low specificity and positive predictive value in low-prevalence populations; thus, reflex direct HR-HPV testing should be performed in p16 immunopositive cases. This two-step approach is viable in resource-limited settings, as the proportion of p16 positive cases is small.

Role of immunohistochemistry in diagnosing round-cell tumours affecting the oral and maxillofacial regions

Background

One of the most challenging spectra of lesions in the oral and maxillofacial region (OMFR) are round-cell tumours (RCTs). They show a considerable degree of overlap in microscopy and immunophenotypes. The main aim of this study is to analyse the spectrum of RCTs encountered in the oral and maxillofacial regions. We emphasise the role of immunohistochemistry (IHC) which in conjunction with histological, clinical, and imaging findings is necessary for their correct characterisation. The secondary objectives are to discuss differential diagnosis, workflow, and diagnostic algorithm for round-cell lesions affecting the OMFR.

Methods

Formalin-fixed, paraffin-embedded sections of RCTs were retrieved from the archives of the Department of Oral Pathology (January 2018 to March 2020). These cases were analysed by three pathologists independently by evaluating haematoxylin and eosin-stained sections, and immunohistochemical markers employed to characterise these lesions.

Results

Under the spectrum of RCTs, 11 cases (0.53%) were diagnosed with a predominance of non-Hodgkin lymphoma (55%) followed by Ewing sarcoma (18%). The remaining were Langerhans cell histiocytosis (9%), neuroendocrine carcinoma (9%), and sinonasal undifferentiated carcinoma (9%). Except for one case, in all cases, the final diagnosis was established with the use of adjunctive IHC.

Conclusion

RCTs can pose a diagnostic challenge for inexperienced oral pathologists. Thorough knowledge of the differentials of RCT occurring in oral and maxillofacial is helpful. An algorithm-based diagnostic approach incorporating the clinical, imaging, and histomorphological findings and immunohistochemical evaluation can help in minimizing diagnostic confusion and errors.

Epithelioid inflammatory myofibroblastic sarcoma arising in the maxilla: first reported case in the jaws

Epithelioid inflammatory myofibroblastic sarcoma (EIMS) is a rare variant of inflammatory myofibroblastic tumors located mostly in the intra-abdominal region. Herein, we present a case of a 32-year-old male with a lobulated growth in the right maxilla. Radiology revealed a solitary osteolytic lesion with an irregular margin, causing buccal and palatal cortex erosion. Histopathology revealed a tumor composed of spindle-shaped fascicles that blend into sheets of round to ovoid-shaped epithelioid cells, areas of myxoid changes, and necrosis. Tumor cells showed a moderate amount of eosinophilic cytoplasm, large vesicular nuclei with coarse chromatin, nuclear pleomorphism, and increased mitoses. Tumor cells were immunopositive for ALK-1, focal positivity for smooth muscle actin, panCK, epithelial membrane antigen, and immunonegativity for CD 30, desmin, CD34, and STAT6. P53 showed a wild-type staining pattern, and INI-1 expression was retained. The Ki-67 proliferative index was 22%. To the best of our knowledge, this is the first case of EIMS occurring in the maxilla.

Sclerosing epithelioid fibrosarcoma of the kidney

A woman in her 20s presented with headache and back pain and was found to have a left renal mass with bony metastases. She underwent nephrectomy, and on histopathology was initially diagnosed with stage 4 clear cell sarcoma of the kidney. She underwent palliative radiation and chemotherapy; however, the disease progressed and she came to our centre. We started her on second-line chemotherapy and submitted her tissue blocks for review. Due to her age and lack of sclerotic stroma in the tissue, we had our doubts about the diagnosis and hence, tissue sample was submitted for next-generation sequencing (NGS). NGS detected an EWSR1::CREBL1 fusion, clinching the final diagnosis of sclerosing epithelioid fibrosarcoma of the kidney, a singular diagnosis rarely reported in the literature. Currently, the patient is post her third line of chemotherapy, is on maintenance, and is doing well and has resumed her daily activities.

Virological and cytological changes in tears and conjunctiva of patients with COVID-19

Purpose

To analyze the presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in tears/conjunctival epithelium and assess the cytomorphological changes in the conjunctival epithelium of coronavirus disease 2019 (COVID-19) patients.

Methods

In this pilot study, patients with moderate to severe COVID-19 were recruited from the COVID ward/intensive care unit of the institute. Tears and conjunctival swabs were collected from COVID-19 patients and sent to the virology laboratory for reverse transcription polymerase chain reaction (RT-PCR) testing. Conjunctival swabs were used to prepare smears, which underwent cytological evaluation and immunocytochemistry for SARS-CoV-2 nucleocapsid protein.

Results

Forty-two patients were included. The mean age of participants was 48.61 (range: 5-75) years. Seven (16.6%) patients tested positive for SARS-CoV-2 ribonucleic acid in tears samples, four (9.5%) of which were positive on conjunctival swab by RT-PCR in the first test. Cytomorphological changes were observed significantly more in smears from patients with positive RT-PCR on tear samples, including bi-/multi-nucleation (p = 0.01), chromatin clearing (p = 0.02), and intra-nuclear inclusions (p < 0.001). One case (3.2%) showed immunopositivity for SARS-CoV-2; this patient had severe disease and the lowest Ct values for tear and conjunctival samples among all positive cases.

Conclusion

Conjunctival smears from patients with COVID-19 revealed cytomorphological alterations, even in the absence of clinically significant ocular infection. However, viral proteins were demonstrated within epithelial cells only rarely, suggesting that although the conjunctival epithelium may serve as a portal for entry, viral replication is possibly rare or short-lived.

Fine needle aspiration cytology of metastatic SMARCA4-deficient sinonasal teratocarcinosarcoma: First report in literature

Inactivating mutations of SMARCA4 and accompanying loss of BRG1 immunoexpression were recently identified in majority of sinonasal teratocarcinosarcomas (TCS). These rare and aggressive neoplasms have potential for nodal metastasis, presenting opportunities for diagnosis on fine needle aspiration cytology (FNAC). However, their cytological features have not been described till date. A 22-year-old male was diagnosed to have SMARCA4-deficient TCS on a nasal mass biopsy, and was started on neoadjuvant chemotherapy. Four months later, FNAC from cervical lymph nodes showed predominantly discohesive tumor cells with moderate to abundant cytoplasm and enlarged vesicular nuclei with prominent nucleoli. Occasional cohesive fragments showed ovoid to spindled tumor cells attached to fibrovascular cores. Few loosely cohesive cells with scant cytoplasm and nuclei having stippled chromatin, and rhabdoid cells were also seen. Frequent mitoses, apoptosis and nuclear streaking were evident. Overt squamous or glandular differentiation was absent. Tumor cells showed loss of BRG1 immunostaining and β-catenin immunopositivity on a cell block, consistent with metastatic SMARCA4-deficient TCS. The diversity of cell types in SMARCA4-deficient TCS can result in a broad spectrum of cytological features that overlap with that of other regional metastatic tumors including neuroendocrine carcinoma, olfactory neuroblastoma and melanoma. Further, all components of TCS as seen in the primary tumor may not be present in nodal metastases. Thus, SMARCA4-deficient TCS should be considered in the differential diagnosis of metastatic poorly/undifferentiated malignancies in cervical lymph node aspirates, and appropriate ancillary tests viz. BRG1 immunostaining employed for accurate diagnosis.

Fluorescence in situ hybridization for ETV6 gene rearrangements on destained cytological smears: Role in diagnosis of secretory carcinoma of salivary gland

BACKGROUND

Fine-needle aspiration cytology (FNAC) is the first-line diagnostic procedure for salivary gland masses. Secretory carcinoma (SC) is characterized by ETV6 and RET rearrangements detected by fluorescence in situ hybridization (FISH) or reverse transcriptase-polymerase chain reaction optimized for paraffin-embedded and fresh-frozen tissue, respectively. The authors performed FISH on cytological material to assess its role in the diagnosis of SC.

METHODS

FNACs with SC as a diagnostic consideration and cases diagnosed as SC on histology with a corresponding FNAC with any diagnosis were evaluated for ETV6 rearrangement by FISH. If acinic cell carcinoma (ACC) was a differential diagnosis and ETV6 rearrangement was absent, NR4A3 FISH was performed. FISH results were compared with those on histological specimens, where available.

RESULTS

Fifteen cases were included. FISH initially performed on three cell blocks did not yield good results, was then performed on direct smears, and was interpretable in 14 cases (93.3%). An ETV6 rearrangement was identified in seven cases (50%), and an NR4A3 rearrangement was identified in three cases (21.4%), providing a confirmatory diagnosis in 10 of 15 cases (66.7%). The Milan System for Reporting Salivary Gland Cytopathology category was altered in two cases (6.7%). Complete correlation (100%) was seen with FISH on corresponding histological specimens.

CONCLUSIONS

With minor modifications, the FISH procedure can be optimized for FNAC smears with results comparable to those on histological specimens. ETV6 FISH testing on cytological smears in cases suspected as SC improves the diagnostic accuracy of FNAC and can help lower the proportion of the Milan categories salivary gland neoplasm of uncertain malignant potential and suspicious for malignancy, maximizing diagnostic information from less invasive samples and aiding in patient management.

Immunohistochemical Analysis of the Expression of Cytokeratins in Acquired Cholesteatoma and Its Clinico-Radiological Correlation

Background and Objectives

: Cholesteatomatous chronic otitis media acquires epithelial proliferation and differentiation characteristics, which render it able to erode the underlying bone and cause complications. We attempt to characterize the cholesteatoma epithelium by observing the expression of cytokeratins (such as 34ße12, CK17, and CK13) and Ki67 among patients with cholesteatoma with different aggressiveness as compared to disease-free controls.

Subjects and Methods

: In this prospective study (2017-2021), we enrolled all consenting consecutive patients with cholesteatomatous chronic otitis media. They were staged in accordance with the staging guidelines of the European Academy of Otology and Neurotology and the Japanese Otological Society. Bony external auditory canal (EAC) skin specimens of the patients undergoing tympanoplasty were chosen as controls. We did an immunohistochemical analysis of the cholesteatoma specimens and normal bony EAC controls by observing the expression of 34ße12, CK17, CK13, and Ki67 across the layers of the epithelium. Fisher's exact test and chi-square test were used to evaluate any statistical significance between the cases and the controls, and the subgroups were made based on the clinical stage.

Results

: An increased expression of CK17 (p<0.001), CK13 (p<0.03), and Ki67 (p<0.001) was observed in cholesteatoma specimens when compared to normal bony EAC controls. Also, there was a loss of expression of 34ße12 in a subset of cholesteatoma specimens, all of which showed full-thickness expression of CK13. There was no difference in the expression of cytokeratin among specimens from patients belonging to different subgroups based on clinical stage, age, sex, duration of ear symptoms, or type of hearing loss (conductive vs. sensorineural).

Conclusions

: The majority of cholesteatoma specimens significantly overexpressed CK17, CK13, and Ki67 when compared to normal bony EAC skin controls, while a subset showed loss of expression of 34ße12, which provides some insight into its pathogenesis.

Recurrent Dermatofibrosarcoma Protuberans of the Head and Neck: a Case Series

Dermatofibrosarcoma protuberans (DFSP) is a rare cutaneous sarcoma that develops from dermal fibroblasts and spreads within the dermis and subcutaneous fat. It is locally aggressive, with a high local recurrence rate after excision but has extremely low metastatic potential. In the case of recurrent tumors, surgical excision with adequate margins is the gold standard treatment and may require adjuvant radiotherapy or chemotherapy in some cases. We conducted a retrospective analysis of individuals with dermatofibrosarcoma protuberance of the head and neck region that had treatment at our facility between 2016 and 2021. We gathered the data on the surgical techniques, reconstructive techniques used, histopathological features, adjuvant therapy, and outcomes. We treated three patients with head and neck dermatofibrosarcoma protuberance: one scalp lesion and two on the cheek. All three patients had recurrent tumors, two of whom were treated elsewhere for the primary lesion. One patient underwent surgery for a benign spindle cell tumor of the right cheek, but a final histopathological examination revealed dermatofibrosarcoma protuberance, and the tumor recurred within 3 months. The duration of recurrence is between 3 and 24 months. The size of the tumor ranges from 7.2 to 10.5 cm. The wide local excision margins range from 2 to 4 cm. Reconstruction ranges from split skin graft to regional flap. Inadequate margins raise the possibility of local recurrence in dermatofibrosarcoma protuberance.

Top 10 Clear Cell Head and Neck Lesions to Contemplate

BACKGROUND

Optically clear cytoplasm may occur in neoplastic and non-neoplastic conditions, either as a characteristic feature of a disease entity or as a morphologic rarity, potentially creating diagnostic dilemmas in various organ systems. In the head and neck, clear cell change can occur in lesions of salivary, odontogenic, thyroid, parathyroid, or sinonasal/skull base origin, as well as in metastases to these regions.

METHODS

This review elaborates the top ten clear cell lesions in the head and neck, emphasizing their distinguishing histologic, immunohistochemical, and molecular attributes, and presents a rational approach to arriving at an accurate classification.

RESULTS

Cytoplasmic pallor or clearing may be caused by accumulations of glycogen, lipid, mucin, mucopolysaccharides, water, foreign material, hydropic organelles, or immature zymogen granules. Overlapping morphologic features may present a diagnostic challenge to the surgical pathologist. Similarity in immunohistochemical profiles, often due to common cell type, as well as rare non-neoplastic mimics, furthers the diagnostic conundrum.

CONCLUSIONS

The top ten lesions reviewed in this article are as follows: (1) clear cell carcinoma (salivary and odontogenic), (2) mucoepidermoid carcinoma, (3) myoepithelial and epithelial-myoepithelial carcinoma, (4) oncocytic salivary gland lesions, (5) squamous cell carcinoma, (6) parathyroid water clear cell adenoma, (7) metastatic renal cell carcinoma (especially in comparison to clear cell thyroid neoplasms), (8) sinonasal renal cell-like adenocarcinoma, (9) chordoma, and (10) rhinoscleroma.

The Role of Serum Galactomannan Assay as a Potential Surrogate Biomarker for Fungal Microinvasion in Allergic Fungal Rhinosinusitis

We conducted this study to determine if serum galactomannan (GM) can be used as a marker to implicate the invasiveness of allergic fungal rhinosinusitis (AFRS), and correlate this value with the aggressiveness of disease documented via computed tomography (CT). All paranasal CT scans done for AFRS patients prospectively over a five-year period (2015-2019) were included. An indigenous 20-point score was used to document the extent of bone erosion seen on CT, wherein a higher score meant a greater extent of bone erosion. It was then correlated with serum GM scores. The median CT scores of galactomannan-positive (GM+) patients were compared with the median CT scores of galactomannan-negative (GM-) patients 3 using Mann-Whitney U test. The patients were divided into five groups based on the extent of disease-No bone erosion, erosion of only sinus wall/orbit, 3 erosion of orbit and skull base, erosion of only skull base and lateral extension of disease into infratemporal fossa (ITF). Subgroup analysis was conducted over mean GM values in these groups using ANOVA test. p-value < 0.05 was considered significant. Statistical analysis was performed using SPSS version 25.0. A total of 92 patients were included (56 males, 36 females). No statistically significant difference was found (p-value = 0.42) between the CT scores of galactomannan-positive (GM+) group and galactomannan-negative (GM-) group. The mean GM scores amongst the five sub-groups did not show a statistically significant difference. Serum galactomannan values correlate poorly with aggressiveness of disease quantified on non-contrast CT of paranasal sinuses.

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.

SMARCA4-deficient Undifferentiated Uterine Sarcoma: Clinicopathological Features of an Emerging Entity

SMARCA4-deficient undifferentiated uterine sarcoma is a recently described molecularly defined entity among the subset of aggressive undifferentiated uterine tumors. Mutation in the SMARCA4 gene is a key driver alteration, as also seen in small cell carcinoma of ovary, hypercalcemic type (SCCOHT) and thoracic undifferentiated carcinoma. Limited number of cases of SMARCA4-deficient undifferentiated uterine sarcoma has been reported in literature. We hereby describe a case of this distinct entity in a 52-year-old woman. Histomorphological examination showed sheets of monomorphic epithelioid cells with a variable proportion of cells displaying rhabdoid features, brisk mitotic activity, and lymphovascular invasion. A panel of immunohistochemical markers was required to exclude the differential diagnoses. The tumor was microsatellite stable. Loss of SMARCA4 expression and intact expression of INI1 in tumor cells by immunohistochemistry (IHC) confirmed the diagnosis of SMARCA4- deficient undifferentiated uterine sarcoma. The patient had a rapidly progressive clinical course.

Cytological diagnosis of olfactory neuroblastoma at metastatic sites, with emphasis on role of insulinoma-associated protein 1 immunocytochemistry

BACKGROUND

Olfactory neuroblastoma (ONB) is a rare neuroectodermal tumor with a propensity for lymph node and distant metastases in a proportion of cases, presenting opportunities for cytological diagnosis. Insulinoma-associated protein 1 (INSM1) is a recently identified marker of neuroendocrine differentiation with higher sensitivity and specificity than traditional neuroendocrine immunostains used in diagnosis of ONB.

METHODS

Archival aspirates diagnosed as metastatic ONB were retrieved and reviewed for described characteristics of ONB. Spare direct smears with sufficient cellular material from each case were selected, if available, and immunocytochemistry for INSM1 was performed on the destained alcohol-fixed smears. INSM1 was also performed on non-neuroendocrine malignant round cell tumors (MRCT).

RESULTS

Seven fine needle aspirates (FNA) from five patients were identified, all of which showed a small round cell tumor with fine to coarse granular chromatin. Most cases had moderate to high cellularity, comprised of loosely cohesive clusters and dispersed cells. While two-cell pattern, nuclear streaking and moulding were frequent, background neuropil, fibrillary cytoplasm, and rosettes were uncommon. INSM1 immunostaining performed on spare direct smears showed strong positivity in 30%-100% of tumor cells (mean: 62%) in all aspirates tested (100%). In comparison with other immunostains, INSM1 showed more robust staining, and was easier to interpret. All non-neuroendocrine MRCTs were negative for INSM1.

CONCLUSION

Metatstatic ONB can resemble other small round cell tumors, as all the diagnostic features of ONB may not be readily evident. INSM1 immunocytochemistry has high sensitivity and specificity and can reliably be used as a single marker to support the cytomorphology for a confirmatory diagnosis of ONB, even on direct smears if a cell block is not available.

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.

Pleural metastasis from parotid secretory carcinoma: First report of morphology on effusion cytology, and role of pan-TRK immunohistochemistry

Distant metastasis from salivary gland secretory carcinoma (SC) is rare, with lung and pleura being the most frequent site. While cytological features of SC on fine needle aspirates are well documented, its morphology in serous effusions has not been described. We describe the cytomorphological features on effusion cytology of two patients with ETV6::NTRK3 fusion-positive SC, who subsequently developed pleural metastases. Cytospin preparations of pleural fluid showed tightly cohesive, irregularly shaped and ball-like clusters of large tumor cells with scant to abundant uni- and multi-vacuolated cytoplasm. Nuclei were eccentrically placed, round to oval, vesicular, with finely granular chromatin, irregular nuclear membranes and conspicuous to prominent nucleoli. With these features, the tumors resembled an adenocarcinoma, indistinguishable from a lung primary. Cell blocks from both cases showed tumor fragments, some of which had the hollow appearance of transversely sectioned cell spheres as seen in lung and breast adenocarcinomas. Immunohistochemistry on cell blocks revealed nuclear pan-TRK positivity in both cases. Case 1 also showed focal mammaglobin staining, and TTF1 negativity. Pleural metastases from SC may mimic other adenocarcinomas. As targeted therapy, that is, selective TRK inhibitors are available for treatment of metastatic disease, NTRK3 fusion status is not only diagnostic, but also required to plan treatment. Pan-TRK immunohistochemistry serves as a viable cost-effective, easy to apply surrogate marker for NTRK3 fusion, particularly in diagnostic laboratories lacking easy access to molecular testing on cytological material.

Fine-needle aspiration cytology of adamantinoma-like Ewing sarcoma: An unusual parotid tumor

Adamantinoma-like Ewing sarcoma (ALES) is a histological subtype of Ewing sarcoma that demonstrates the morphological and immunohistochemical features of the latter, harbors the EWSR1::FLI1 gene fusion, and additionally demonstrates complex epithelial differentiation on morphology and immunohistochemistry. Accurate preoperative diagnosis has potential to inform management and improve patient outcome. Cytomorphology of ALES is not well documented, with available reports showing a spectrum of features. An aspirate from a 30-year-old male with a swelling in right parotid region, interpreted elsewhere as acinic cell carcinoma (ACC), was submitted to us for review. Smears showed dispersed cells and loosely cohesive clusters with scant cytoplasm and large nuclei with focal nuclear molding, prompting a diagnosis of malignant neoplasm, possibly neuroendocrine carcinoma. Cytoplasmic vacuoles and tigroid background were present focally, the former of which had possibly led to interpretation as ACC. No material was available for ancillary tests. Parotidectomy revealed features of ALES. The cytological features of ALES in the parotid overlap with several basaloid and round blue cell neoplasms that are more common at this site. ALES should be considered in all salivary gland aspirates with isomorphic small round or basaloid cells, with or without the presence of squamous differentiation. Rosettes, cytoplasmic vacuoles, and a tigroid background are subtle morphological clues to the diagnosis, which if suspected on cytomorphology, can be confirmed using ancillary techniques.

Recurrent pleomorphic adenoma: unusual cause of isolated sphenoid sinus lesion

Pleomorphic adenoma is the most common benign salivary gland tumour of the head and neck region, most commonly seen in parotid glands. These may arise also from minor salivary glands of the upper aerodigestive tract comprises the upper lip, cheek, floor of the mouth and rarely from mucoserous glands in the nasal cavity and paranasal sinuses. A middle-aged man, who had undergone surgery for a nasal mass 14 years ago, presented with headache and visual complaints from a recurrent mass originating from the sphenoid sinus. Isolated sphenoid sinus space-occupying lesions have always been a diagnostic challenge. The mass was biopsied and diagnosed as pleomorphic adenoma on histopathology, and then excised endoscopically. Early and accurate diagnosis on a biopsy may result in complete excision of the tumour and prevent recurrence. The endoscopic route is preferred for surgical excision and the patient should be followed up clinically and radiologically to detect early recurrence.

Role of Whole body PET/CT and Examination under anesthesia with multi-site biopsy in evaluating CUP

To evaluate the role of 18FDG-WBPET-CT, Examination under anesthesia (EUA), and multiple-site biopsy in detecting the occult site in head & neck carcinoma of unknown primary (HN-CUP). In this prospective study, 22 patients with diagnosed CUP, after a thorough outpatient endoscopic evaluation of upper airway and radiological evaluation (CT/MRI) that ruled out a primary lesion were included. These patients subsequently underwent whole-body PET-CT and EUA. Based on the presence of suspicious findings ( +) or their absence (-) on 18FDG-WBPET-CT (P) and EUA (E), we divided the patients into 5 groups: P-E-, P-E + , P + E-, P + E + , and P + or E + . All these patients underwent bilateral palatine tonsillectomy, bilateral nasopharyngeal biopsy, and ipsilateral lingual tonsillectomy for identification of occult primary. Out of 22 patients, the primary could be detected in 4 patients (18%) after the workup (three in the oropharynx and one in the hypopharynx, all ipsilateral). 18FDG-PET-CT suspected primaries in 7 patients; biopsy was positive for three (sensitivity-75%, specificity-77%, PPV-43%, NPV-93%). Out of 5 patients, who had suspicious findings on EUA, 3 of the biopsies revealed malignancy (sensitivity-75%, specificity-88%, PPV-60%, NPV-94%). Both PET-CT and EUA when combined, yield a NPV of 100% if both are negative and PPV of 100% when both are positive for suspicious findings. No primary was identified in the absence of a suspicion by PET-CT or EUA. Without a suspicion on 18FDG-WBPET-CT and EUA, there is a limited role of multiple-site biopsies in patients of HN-CUP.

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.

Malignancy mimics- diagnostic perplexities for oral and maxillofacial pathologists

Objective

In pathology practice, one frequently encounters benign lesions which superficially resemble malignancy clinically and histopathologically. The diagnostic pitfalls can be avoided if the approach exemplified in the present study is followed. We expect that familiarity of these cases will be helpful for pathologists at the beginning of their career.

Methods

Clinical case records of all the pathological specimens reported in our laboratory from January 2018 to September 2019 were queried. Cases displaying pseudotumor features were reviewed along with the special stains were performed and immunohistochemistry (IHC) studies. A working classification of pseudotumors presenting in the oral cavity was proposed.

Results

Immunoglobulin G4-related disease, nodular fasciitis, fibrolipoma, odontogenic keratocyst with giant cell granuloma, juvenile ossifying fibroma with central giant cell granuloma and tumor-induced osteomalacia were the most common diagnoses where the tissue specimens resembled malignancies on routine clinicoradiological evaluation and light microscopy of tissue specimens. Their differential diagnosis and the pathological diagnostic dilemmas are explained. We have also highlighted the importance of correlating clinical, radiological and microscopic details with the findings deduced from advanced pathological aids to establish the final diagnosis.

Conclusions

Pathologists should be aware of the conditions where the diagnosis of malignancy needs stricter evaluation to rule out malignant mimics. In such scenarios, correlation of light microscopy findings with clinical and radiological details cannot be overemphasized. Advanced pathological aids such as IHC, where necessary are often indispensable for reaching the accurate diagnosis in these cases.

Metastases to the Parotid Gland: Study from a Tertiary Care Centre

BACKGROUND

Metastases account for 6-25% of parotid tumors, often presenting dilemmas in their diagnosis.

METHODS

Parotid metastases diagnosed on histology/cytology were retrieved. MUC2, MUC5AC, androgen receptor immunohistochemistry was performed in select cases.

RESULTS

Fifty-one samples were identified from 42 patients, including 14 aspirates, 7 biopsies and 30 parotidectomies. Previous history was available in 17 cases, 13 parotidectomies accompanied excision of the primary, and relevant clinical data was unavailable for 12 patients. Majority (81%) had head and neck primaries; eye and ocular adnexa were the commonest subsite (52.4%), and sebaceous carcinoma the commonest histology (33%). When history was unavailable, most metastases were initially diagnosed as poorly differentiated carcinoma/malignant tumor, or mucoepidermoid carcinoma on cytology.

CONCLUSIONS

Intraparotid metastases encompass a wide spectrum, often mimicking primary salivary gland neoplasms, particularly on limited samples. Metastases should be considered when histological/cytological features are unusual; detailed clinical information and ancillary techniques aid in arriving at an accurate diagnosis.

An unusual testicular mass in a young male: Metastasis from occult gastric carcinoma

Metastases to the testis are uncommon. Signet-ring cell carcinomas from the gastrointestinal tract (GIT) can rarely disseminate to the testicles, mimicking primary testicular malignancies with signet-ring cells. We hereby describe a case of a 26-year-old male who presented with left testicular swelling, multiple lymphadenopathies, and normal serum tumor markers. Lymph node biopsy revealed clusters and singly lying signet-ring cells. Judicious use of immunohistochemistry confirmed the tumor to be GIT primary. Further investigations confirmed a gastric tumor extending to the duodenum. Although rare, metastatic tumors to the testis should be considered in differential diagnoses of testicular masses in a young patient, particularly when serum germ cell tumor markers are normal or mildly deranged.

Negative 68Ga-Prostate-Specific Membrane Antigen PET/CT Scan on a Recurrent Juvenile Nasopharyngeal Angiofibroma

ABSTRACT

We present the case of a left-sided recurrent juvenile nasopharyngeal angiofibroma (JNA) in a 16-year-old boy who underwent endoscopic excision 2 years back. The preoperative contrast-enhanced MRI and histopathology were in favor of JNA. The follow-up 68Ga-prostate-specific membrane antigen (PSMA) PET/CT scan at 3-month interval revealed complete clearance of disease. Currently, the patient presented with recurrent bleeding and nasal endoscopic examination, and contrast-enhanced MRI revealed a presence of a recurrent tumor. The tumor did not show any uptake on 68Ga-PSMA PET/CT, and postoperative histopathology evaluation confirmed the presence of JNA. Although regarded as a criterion-standard imaging modality for assessment of recurrent or residual JNA, 68Ga-PSMA PET/CT is never 100% specific.

Role of MDM2, CDK4, BCL2, Parafibromin and Galectin 1 in Differentiating Osteosarcoma from its Benign Fibro-osseous Lesions

Benign fibro-osseous lesions (BFOLs) are a diverse group of lesions showing considerable degree of overlap with low grade osteosarcoma (LGOS). Further, de-differentiated osteosarcoma (DOS) is usually indistinguishable from conventional high-grade OS (COS) if LGOS foci are not identified. Thus, there is a need for adjunctive immunohistochemical markers to differentiate OS from benign FOLs as well as DOS from COS. This study evaluated the role of immunohistochemical expression of MDM2, CDK4, parafibromin, BCL-2 and Galectin-1 (Gal-1) in accurate characterization of benign FOLs and in differentiating them from OS. From our archives, we retrieved 101 tissue samples which were diagnosed as osteosarcoma (OS) /ossifying fibroma (OF) / fibrous dysplasia (FD) or fibrous hyperplasia (FH) and examined their immunohistochemical staining pattern with the aforementioned antibodies. MDM2 showed 100% specificity for diagnosing OS. CDK4 and Gal-1 showed linear increase in immunoexpression from benign BFOLs to OS. BCL-2 showed equivocal immunopositivity in OF and OS, but the positivity was higher than that observed in FD. The highest immunoexpression for parafibromin was seen in FD followed by OF and OS cases. Thus, MDM2 is most specific, and Gal-1 is most sensitive of all the markers studied in differentiating OS from benign mimics. Combination of these two markers can be used as an adjunct to conventional imaging and microscopy in accurate characterization of these lesions. Further MDM2 overexpression can differentiate DOS and COS.

Demographic Profile of p16 Immunopositive and HPV DNA PCR Positive Oral Squamous Cell Carcinoma in a Large Cohort of Indian Patients

Background:

The Indian subcontinent has the highest incidence of oral cavity squamous cell carcinoma in the world. The high incidence of tobacco chewing habit with or without smoking has been found to be the chief culprit. However in a minor subset of patients Human Papilloma Virus may play a role.

Materials and Methods:

A total of 800 cases of Oral squamous cell carcinoma were included in the study. The patients were given a questionnaire comprising of questions about demographic details and habits. The biopsy samples were routinely processed for immunohistochemistry for p16 (E6H4 clone, CINtec histology, Roche diagnostics). Cases with 2+/3+ positive nuclear staining with more than 75% cells immunopositive were taken as p16 immunopositive as per the AJCC criteria and were further subjected to HPV DNA PCR for which DNA was extracted from the formalin fixed paraffin embedded tissue.

Results:

Out of 800 OSCC cases 139 (17.37%) showed p16 immunopositivity by AJCC criteria. Out of these, 104 (104/139, 74.8%) cases were positive by HPV DNA PCR for HPV-16/18. Following patient characteristics were associated with a higher proportion of p16 and HPV DNA positivity–urban residence, vegetarian diet, illiteracy, graduate or higher education. No correlation was noted with gender, tobacco smoking or chewing habits, religion, occupation or site of tumor. The p16 immunopositivity was higher in the younger age group with no tobacco habits.

Conclusion:

A significant proportion of OSCC cases in India are associated with HPV infection. A higher percentage of p16 immunopositivity amongst younger patients with no tobacco habits points towards a distinct subset of patients in whom HPV may be the chief culprit and not just playing a supporting role.

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.