Differentiated Thyroid Cancers with Synchronous Second Primary Cancers: Case Series.

The incidence of synchronous second primary cancer (SSPC) with DIfferentiated Thyroid Cancers (DTC) is a very rare entity. Very few case reports and case series were published in the literature. To enumerate the clinicopathological data of patients with DTC with SSPC. This is a single-center retrospective study. All the patients diagnosed with DTC and SSPC from January 2016 to July 2023 were included in the study. The demographic, clinicopathological data, and survival data were collected from the institute's database. Twelve patients were found to have DTC with SSPC. All the patients had papillary thyroid cancer. Ten patients had head and neck squamous cell carcinoma, one patient had malignant phyllodes tumor, and another patient had endometrioid adenocarcinoma as the SSPC. Six patients were diagnosed during preoperative evaluation, one patient was diagnosed 3 months after the oral malignancy diagnosis, and five patients were diagnosed with PTC in cervical nodes after neck dissection. Complete thyroid removal was done in six patients and hemithyroidectomy in two patients. The median follow-up was 25.55 months. The median overall survival was 40.97 months. Head and neck SCC is the most common SSPC with DTC. Since these are rare scenarios multi-disciplinary panel discussion can help in deciding management.

Histomorphological Spectrum and Diagnostic Challenges in Thymic Epithelial Neoplasms with their Prognostic Significance: A Case Series of 33 Cases at a Regional Cancer Center in Western India.

Jahnavi Gandhi, DCPObjective Pathological diagnosis of thymic epithelial neoplasms is challenging due to multiple subtypes, tumor heterogeneity, and variations in inter-observer reproducibility. Very few studies are available on their spectrum in the Indian subcontinent. In this study, we aimed to explore the morphological spectrum and diagnostic difficulties in the classification and subtyping of thymic epithelial neoplasms along with their prognostic significance in the Indian population. Material and Methods Retrospectively, all surgically resected thymectomy specimens operated at our institute as well as outside review cases during the period were included. Histomorphology and immunohistochemistry (IHC) slides were reviewed and correlated with clinicopathological variables. Statistical Analysis Microsoft Excel 2019 and SPSS version 20 were used for data analysis. Results Among the 33 thymic epithelial neoplasms operated during the study period, the commonest subtype was thymoma B2 type followed by AB, B1, A, and B3 types. A single case each of micronodular thymoma, microscopic thymoma, and thymic carcinoma were identified. Six cases of thymomas with more than one pattern (other than 'A') were noted. The male:female ratio was 2:1. Stage I in Modified Masaoka staging and pT1a in TNM staging were most common. Seven cases had metastasis, four during initial presentation and three during subsequent follow-up. Discussion and Conclusion Thymic epithelial neoplasms show morphological overlapping of features. Thorough sampling, morphology, and IHC for exact subtyping of thymoma and diligent search and documenting of lymphovascular invasion (LVI) are vital as both are separate risk factors for metastasis/recurrence and help the clinician in a better follow-up of patients.

Urachal inflammatory myofibroblastic tumor with FN1: : ALK fusion: A case report and literature review.

Urachal tumors are rare and comprise of both benign and malignant neoplasms. Epithelial origin tumors are more common than mesenchymal origin tumors. We report a case Urachal inflammatory myofibroblastic tumor (IMFT) in a 12 year old boy who presented with symptoms of lower abdominal pain and burning micturition. Upon evaluation was found to have a soft tissue mass anterior to urinary bladder wall. A laparoscopic excision of tumor was done. Histopathological and immunohistochemical examination confirmed the diagnosis of IMFT. Next generation sequencing identified FN1-ALK gene fusion.

Role of Pap Smear Cervical Cytology in the Diagnosis of Extrauterine Malignancies: Largest Study of 104 Cases from Tertiary Care Cancer Centre in India.

INTRODUCTION: Extrauterine malignancies in cervical samples are rarely seen. It is important to differentiate these cells from those of primary uterine malignancies to determine appropriate line of further investigations and management. Literature on these lesions is limited largely restricted to case reports. The aim of the present study was to study the spectrum and cytomorphological features of extrauterine malignancies in cervical Pap smears. MATERIALS AND METHODS: It is a retrospective and descriptive study conducted in Department of Cytopathology from January 2019 to July 2023. All cases of extrauterine malignancies with available cytology material were included in this study. All cases of primary uterine malignancies, i.e., uterine corpus or cervix confirmed by clinical, radiological, and histopathological examination were excluded. RESULTS: 104 out of 11,674 cytology Pap smears were those of extrauterine malignancy. Diagnosis of extrauterine malignancy was given in 47.1% cases, 30.9% were reported as positive for malignancy without giving the possibility of an extrauterine origin, and 22.0% were reported as atypical glandular cells only. In 56 cases where Pap smear was the first investigation which led to the diagnosis. Most common extrauterine malignancy was adenocarcinoma principally from ovarian, colorectal, and vaginal origin. Other epithelial malignancies noted were urothelial carcinoma and invasive breast carcinoma. Among non-epithelial malignancies, we reported vaginal mucosal melanoma, cutaneous melanoma, acute leukaemia, and anaplastic large cell lymphoma. CONCLUSION: High index of suspicion, presence of squamous and glandular elements with no atypical features, and occasional clusters of cells with marked atypia and usually no necrosis in the background are helpful cytomorphological clues to raise suspicion for extrauterine malignancy. Correlation with serology, radiology, and immunocytochemistry can help in reaching final diagnosis.

Cytologic Parameters in Predicting the Outcome of Atypical Glandular Cells on Papanicolaou Smears: A Single-Institutional Experience.

Background: Atypical glandular cells (AGCs) diagnosis on Pap (Papanicolaou) smears are uncommon and may represent various benign and malignant lesions. Objective: This study aims to report the incidence of AGC on Pap smear, to study the relationship of AGC with malignancy, and to determine cytomorphological features that help in predicting malignancy. Materials and Methods: Retrospective analytical study conducted in the Department of Oncopathology at Tertiary Cancer and Research Institute. In this retrospective study, we included cases diagnosed with AGC between July 2017 to July 2022. All slides were reviewed and subclassified according to the Bethesda 2014 classification system (TBS). The predetermined cytomorphological features observed in the smears were recorded. The follow-up histopathological diagnoses of the cases were retrieved. The significant cytomorphological and clinicopathological findings for malignancy were determined. Results: Pearson χ2 test with SPSS software version 22 to compare cytologic features of cases with benign and malignant follow-up. The significant cytomorphological features observed in neoplastic cases were cells in 3-dimensional clusters, nuclear overlapping, reniform nucleus, irregular nuclear membrane, increased nuclear size, single macronucleoli, engulfed neutrophils, and prominently vacuolated cytoplasm. Conclusions: The diagnosis of AGC on cytology is associated with clinically significant lesions, and cytomorphologic parameters can be used to predict the benign and malignant outcome.

When to settle for SETTLE! A lesson learned from our cases.

Spindle epithelial tumor with thymic like elements (SETTLE) is a biphasic tumor composed of epithelial and spindle cell components. It is an uncommon indolent tumor arising in the thyroid gland and most commonly affects the children and young adults. This entity is mostly overlooked because of its rarity and diagnostic difficulty on morphology. We discuss two cases of SETTLE with varied presentation, diagnostic challenges and lessons learnt from them.SETTLE should be considered as a differential especially when dealing with a thyroid lesion in young and adolescent. The article discusses the histologic details and common mimickers to be borne in mind aiding in arrival at the final diagnosis on biopsy specimens.

International medullary thyroid carcinoma grading system: an Indian tertiary care centre experience.

INTRODUCTION: Medullary carcinoma (MTC) is a rare neuroendocrine thyroid neoplasm. The international medullary thyroid carcinoma grading scheme (IMTCGS), which has prognostic significance, has been introduced recently. The present study graded MTC cases using the IMTCGS and evaluated it in our study cohort. METHODS: All MTC thyroidectomy cases over 6 years were evaluated. Low-grade (LG) and high-grade (HG) were compared. Survival analysis included overall survival (OS), loco-regional free survival and distant metastasis free survival (DMFS). RESULTS: Of 32 cases, 31.25% were HG and 68.75% LG. The mean age was 44.0 years and M:F ratio 1:1.146. HG patients were older and had tumour cells with high-grade nuclear features and prominent nucleoli and showed distant metastasis. Necrosis was found more in patients with high grade nuclear features. There was discordance between the high Ki67 (60%) and increased mitotic activity (20%). Univariate survival analysis revealed poor DMFRS and OS in the cohorts with high grade, Ki67 > 5% and coagulative necrosis. The multivariate cox regression analysis showed IMTCGS significantly associated with overall survival (HR 28.30, p = 0.009) and DMFS (HR 15.70, p = 0.02). DISCUSSION AND CONCLUSION: This is the first Indian study evaluating IMTCGS, a very simple and convenient grading system that can be readily used in any tertiary health care centre. IHC for Ki 67 should mandatorily be done irrespective of the low mitotic activity on the HPE and necrosis should be diligently searched in cases with high-grade nuclear morphology. HG MTC cohorts were associated with poor OS as well as DMFRS.

Does an excision of needle bone biopsy tract affect the prognosis in patients with primary bone tumor?

Background: Opinion remains divided as to whether excision of needle biopsy tract is beneficial and affect the prognosis. The aim of the study was to compare the outcomes in patients of primary malignant bone tumor who had undergone surgery with or without biopsy tract excision. Methods: From January 2017 to June 2020, 240 patients with primary malignant bone tumors who underwent percutaneous needle biopsy followed by surgery were included. We categorized patients into Biopsy tract excision (Group1:185 patients) and Non Biopsy tract excision (Group 2:55 patients). Median follow-up of patients was 58.6 months (range; 12-61.8months). Results: Demographics, histopathological type, tumor location, type of surgery were similar in biopsy tract excision and non excision group. We found biopsy tract seeding in two cases out of 185 (1.1 %). Local recurrence in biopsy tract excision and non excision group was observed in 3.2 % and 1.8 % respectively with p value 0.58. The mean local recurrence free survival rate in group 1 and 2 was 60 and 44 months respectively. Limb salvage was performed in 71.6 % and in amputation in 28.3 % cases. The local recurrence in limb-salvage and amputation group was observed in 3.4 % (6/172) and 1.4 % (1/68) respectively. Conclusion: There was no significant difference in the rate of local recurrence between patients who were treated by biopsy tract excision or non tract excision. Percutenous needle bone biopsy tract leads to minimal risk of tumor seeding during surgical resection of primary bone tumors.We recommend the further multi centre studies with more number of patients to reach a consensus on resection of needle biopsy tract during surgical management of primary bone tumors.

Cystic Hypersecretory Carcinoma of the Breast: A Rare Case Report with Review of Literature and Emphasis on Differential Diagnosis.

Karthik DhandapanCystic hypersecretory carcinoma (CHC) is a rare subset of in-situ breast carcinoma with or without associated invasive carcinoma. It is part of a spectrum of cystic hypersecretory lesions that includes cystic hypersecretory hyperplasia (CHH), CHH with atypia, CHC in situ, and CHC with invasion. Only 20 cases of CHC with invasion have been reported so far. A 60-year-old female presented with a palpable right breast mass. A core needle biopsy was carried out, which was reported as invasive breast carcinoma with areas of ductal carcinoma in situ (DCIS). Modified radical mastectomy was done post-neo-adjuvant chemotherapy; On microscopy, dilated cystic spaces filled with eosinophilic secretions (thyroid colloid-like), lining neoplastic cells with variable degrees of proliferation and atypia were seen. There were multiple foci of invasion; both skin invasion and axillary lymph node metastasis were present. Immunohistochemistry (IHC) was done with relevant markers; correlating all these findings, a diagnosis of CHC with invasion was made. CHC is a distinct form of DCIS with or without associated invasion. Awareness of this entity is required to rule out other differential diagnoses and to avoid misinterpretation. Little is known about the IHC profile, biological behavior, prognosis, and molecular profile of CHC due to its rarity.

A unique coexistence of a plurihormonal pituitary adenoma with granulomatous hypophysitis.

Dual pathology in the pituitary gland is a unique phenomenon. Coexistence of a pituitary adenoma with primary hypophysitis has been reported rarely with very few cases in the literature. Among the primary hypophysitis, primary granulomatous subtype has been proposed to be idiopathic and autoimmune in nature. Plurihormonal pituitary adenomas produce hormones of more than one different pituitary cell lineage. Pituitary adenoma with a single hormonal content has been documented with concurrent primary granulomatous hypophysitis. The present case describes the unique coexistence of a plurihormonal adenoma showing somatotroph, lactotroph, and corticotroph lineage with primary granulomatous inflammation in the sellar region in a 36-year-old woman.

Retinoblastoma with Isolated Parotid Gland Metastasis: A Report of 2 Cases with Review of Literature.

Retinoblastoma, the most common primary intraocular malignant neoplasm in young children, show frequent metastasis to lymph nodes, central nervous system and bones. However, retinoblastoma metastasizing to parotid gland is very rare. We here present 2 cases of isolated parotid gland metastasis in two children with unilateral retinoblastoma. Case 1 was a one-year-old child presenting with left globe lesion which was diagnosed as Retinoblastoma. Post chemotherapy, enucleation was done which on histopathology examination showed retinoblastoma with scleral invasion and anterior chamber seeding. On 3 month follow up, patient presented with left parotid swelling. He underwent Fine needle aspiration cytology (FNAC) and Core needle biopsy which confirmed retinoblastoma metastasizing to parotid following which superficial parotidectomy was done as it was a solitary hotspot on PET-CT followed by localized radiotherapy and chemotherapy. While case 2, a 6-year-old child presented with left parotid swelling with a history of undergoing enucleation 3 months earlier in an outside hospital; Enucleation slides were reviewed in addition to patient undergoing FNAC and Biopsy from parotid swelling, all of which were consistent with Retinoblastoma metastasizing to parotid; This patient was lost to follow up; Although rare with only a few case reports in literature, both the pathologist and the clinician should be aware of retinoblastoma metastasizing to parotid, which when diagnosed and treated promptly has overall better prognosis in the cases reported so far.

Clinico-Pathological Spectrum of Alveolar Soft Part Sarcoma: Case Series from a Tertiary Care Cancer Referral Centre in India with a Focus on Unusual Clinical and Histological Features.

OBJECTIVE: Alveolar soft part sarcoma (ASPS) is characterized by distinctive histomorphology of variably discohesive epithelioid cells arranged in nests and translocation of t(x;17) (p11.2;q25) resulting in ASPSCR1-TFE3 fusion. The aim of the present study is to review the clinical, histopathological, and immunohistochemical profile of ASPS with a focus on unusual histological features. MATERIAL AND METHOD: The present study is retrospective and descriptive. All cases with a diagnosis of ASPS were retrieved with clinical and radiology details. RESULTS: 22 patients of ASPS were identified. The most common site was the lower extremity and the size range was 3-22 cm. 54.5% of the patients had metastasis, with the lung as the most common site. Metastasis preceded detection of primary tumour in two cases. All cases showed similar histopathology of monomorphic epithelioid cells arranged in nests encircled by sinusoidal vasculature. Architecturally, the organoid pattern (81.8%) was followed by the alveolar pattern. 68.2% of the cases showed apple bite nuclei as the predominant nuclear feature. Rare nuclear features included binucleation (n=13), multinucleation (n=8), pleomorphism (n=4), nuclear grooves in three cases and intranuclear inclusion in one case, mitosis (n=5), and focal necrosis (n=6). All cases were positive for TFE3 and negative for AE1/AE3, EMA, HMB45, PAX8, MyoD1, SMA, synaptophysin, and chromogranin. Only two cases showed focal S100 positivity while one showed focal desmin positivity. CONCLUSION: Diffuse strong nuclear TFE3 positivity is sensitive for ASPS in an appropriate clinicoradiological context. Due to the high propensity for early metastasis, complete metastatic work-up and long term follow up is recommended.

Determination of doxepin hydrochloride in spiked human plasma and capsule after derivatization with eosin Y using resonance Rayleigh scattering, second-order scattering and frequency doubling scattering methods.

Doxepin hydrochloride (DOX) is a tricyclic antidepressant drug. Three sensitive spectrofluorimetric methods, namely resonance Rayleigh scattering (RRS), frequency doubling scattering (FDS) and second-order scattering (SOS), were developed and validated for their estimation of doxepin in spiked human plasma and formulation using liquid-liquid extraction method through the formation of an ion pair complex with eosin Y at a pH of 4.5. Various factors affecting fluorescence intensity were optimized, and the reaction kinetics was determined using the Arrhenius equation method. Different scattering methods such as RRS, FDS and SOS were developed at maximum scattering wavelengths λex /λem = 567/567 nm for RRS, 720/360 nm for SOS and 260/520 nm for FDS, respectively. The methods exhibited high sensitivities, and the detection limits for DOX were found to be 0.82, 1.20 and 1.03 ng/ml for RRS, FDS and SOS methods, respectively. The FDS method exhibited the highest sensitivity. The methods were validated using the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use guidelines and applied to determine DOX in capsule and spiked human plasma samples.

Extra-adrenal peripheral neuroblastic tumors: A clinicopathological study of 18 cases.

Background: Peripheral neuroblastic tumors arise from the sympathoadrenal lineage of the neural crest. They have been classified according to the International Neuroblastoma Pathology Committee (INPC) into Four categories according to International Neuroblastoma Pathology Committee (INPC): a) Neuroblastoma (NB) b) Ganglioneuroblastoma (GNB), nodular c) Ganglioneuroblastoma, intermixed, and d) Ganglioneuroma (GN). Because of the rarity of extra-adrenal peripheral neuroblastic tumors, limited information is available regarding the chemotherapy of NB and GNB. A few case reports or case series with a small number of patients have been documented in the literature. Aim: To describe the clinicopathological characteristics of extra-adrenal peripheral neuroblastic tumors. Materials and. Methods: Clinical, histopathological, and immunohistochemistry (IHC) findings of 18 cases were retrieved. Immunohistochemistry at the time of diagnosis was performed using Ventana Benchmark XT. The mean value was calculated using the Microsoft Office Excel 2019 software. Results: The posterior mediastinum was the most commonly affected extra-adrenal site in our study. Neuroblastoma consisted of eight cases (six in children, two in adults), of which four cases were poorly differentiated and the other four cases were differentiating. Two cases had favorable histology. The bone marrow and cervical lymph node metastasis were documented. Of the four GNB cases, one patient developed bone metastasis. All patients of NB and GNB received combination chemotherapy. One out of six GN patients presented with a large retroperitoneal mass encasing the aorta and renal vessels, mimicking a sarcoma. Conclusion: Extra-adrenal peripheral neuroblastic tumors do not pose any diagnostic issue in adequate tissue sampling. In limited material, immunohistochemistry is needed. The chemotherapy regimen has not been standardized due to rarity. Further molecular testing and targeted therapy may be of help in the future.

Transthoracic Fine-Needle Aspiration Cytology of Pulmonary Spindle and Mesenchymal Neoplasms: A Pandora's Box.

INTRODUCTION: Pulmonary spindle cell and mesenchymal lesions are paradox for pathologists due to their rarity, overlapping morphology, and differentials ranging from benign to malignant lesions, and correct diagnosis is essential due to major treatment implications. This study highlights the role of fine-needle aspiration cytology, clot core biopsy, and immunohistochemistry in diagnosis of spindle cell lesions in lung, thus playing a key role in patient management. METHODS: It is a retrospective study of lung FNA with predominantly spindle and mesenchymal cells from 2015-2020 which were classified cytomorphologically into spindle, epithelioid, small round cell, and biphasic, and IHC panels are applied accordingly. FNA from mediastinum and chest wall was excluded. RESULTS: 60 cases of lung FNA with spindle and mesenchymal cells were identified and included 6 benign and 54 malignancies which included 24 primary pulmonary malignancies and 30 metastases. Most common primary malignancy was sarcomatoid carcinoma, and most common metastasis was malignant peripheral nerve sheath tumour. FNA was paucicellular in 7 cases and was reported as benign in 7 cases and malignant in 46 cases. There were two false-negative cases. One case of pulmonary blastoma was reported as inflammatory pseudotumour on cytology, and other case of chondrosarcoma was reported as chondroid tumour. Sensitivity and specificity of FNA in distinguishing benign lesions and malignancies were 93.8% and 100%, respectively. CONCLUSION: FNA along with clot core biopsy/cell block and IHC plays a pivotal role in the subsequent pathway taken for diagnostic or therapeutic management of these patients without the need for second sampling or trucut biopsies in a low resource setting.

Tumor budding as a prognostic indicator in colorectal carcinoma: a retrospective study of primary colorectal carcinoma cases in a tertiary care center.

Colorectal carcinoma (CRC) is the third most common cancer worldwide. Along with many established prognostic factors, tumor budding is emerging as a valuable marker of prognosis. Tumor budding is not yet universally reported but it has recently been suggested in guidelines by ITBCC (International Tumor Budding Consensus Conference). Our aim is to study prognostic implications of tumor budding in CRC. Hundred cases of primary CRC specimens were retrospectively studied from January, 2016, to February, 2017. Tumor bud count and other histopathological parameters were evaluated from hematoxyline and eosin (H & E) stained slides. Survival analysis was done using Cox proportional hazards model. Association of tumor budding and cancer-specific survival was found to be statistically significant (P = 0.018 for average tumor budding and P = 0.035 for highest tumor budding) Tumor budding was found to be significantly associated with other clinicopathological parameters such as T stage, N stage, TNM stage, and lymphovascular invasion with p value < 0.05. Tumor budding is a valuable prognostic indictor for primary CRC and also significantly associated with other prognostic parameters. It should be reported routinely as a guide to prognosis and further management of patients.

Prognostic significance of STAT3 gene expression in patients with glioblastoma tumors: a study from Western India.

OBJECTIVE: Glioblastoma Multiforme (GBM), a devastating the most common primary malignant intracranial brain tumors. In India, the incidence of this malignancy is escalating, however, there are very few studies on this tumor entity from Indian population. The present study sought to investigate the prevalence and prognostic significance of Signal Transducer and Activator of Transcription 3 (STAT3) gene expression in GBM patients from Western India. METHOD: STAT3 gene expression using real-time PCR was detected in total 55 GBM patients. The impact of STAT3 aberrant expression on progression-free survival (PFS) and overall (OS) was analysed using univariate and multivariate survival analysis. The data were analysed using SPSS statistical software and p value ≤0.05 was considered as significant. RESULTS: The aberrant STAT3 expression was found in 85% (47/55) of patients with -1.12 fold change down-regulation in 49% (23/47) and 3.36 fold change up-regulation was noted in 51% (24/47) of patients. In wild type IDH tumors (n=30), down regulation and up regulation of STAT3 was noted in 63% and 27% of patients, respectively, whereas, for IDH mutant GBM tumors (n=25), the incidence of low expression and high expression of STAT3 was noted in 16% and 68% of patients, respectively. Thus, we found that incidence of STAT3 down regulation was significantly high in patients with IDH wild type tumors, whereas, in IDH mutant GBM tumors, the incidence of up-regulated STAT3 was significantly high (P=0.021, χ2=12.81, r=+0.310). In Kaplan-Meier univariate survival analysis, a part from age (P=0.006), tumor location (P=0.025), and KPS score (P=0.002), co-detection of STAT3 up regulation and presence of IDH mutation (P=0.030) remained significant prognostic factors for PFS and OS. In multivariate survival analysis also, co-detection of STAT3 high expression and presence of IDH mutation remained independent prognosticators for PFS (HR=6.45, 95% CI=1.32-31.40, P=0.021) and OS (HR=8.69, 95% CI=1.66-45.51, P=0.010). CONCLUSION: For GBM tumors, STAT3 up-regulation and presence of IDH mutations together predicts better survival. This reflects unique molecular etiology for GBM patients. Therefore, they would be useful in the future for targeted therapy and for clinicians they would be useful for better patient management. However, study on a larger sample size is required for validation.

Soft tissue aneurysmal bone cyst of left hemithorax: An extremely rare case.

Aneurysmal bone cyst (ABC) is a benign expansile cystic lesion that can affect any bone of the skeleton, especially the femur, tibia, and humerus. Lesions with histologic features of an ABC can be originated within soft tissue in exceedingly rare cases. Extra-skeletal ABC may mimic a variety of benign and malignant lesions and can be confused with other common or rare giant cell-rich tumors of soft tissue. Clinical, radiological and histologic correlation are crucial in reaching the correct diagnosis. Here we report a case of an extra-skeletal ABC arising in left hemithorax in a 13-year-old girl and discuss the common differential diagnosis of this rare entity.

The evolving role of molecular pathology in the diagnosis of salivary gland tumours with potential pitfalls.

Salivary gland tumors are diagnostically challenging owing to the morphological diversity within any tumor type and overlapping histomorphology and immunohistochemistry amongst different tumours. In past two decades, rapid progress has been made in the field of understanding the pathogenesis of these tumours with the discovery of many tumour specific translocations and rearrangements. This includes CRTC1-MAML2 and CRTC-MAML2 in mucoepidermoid carcinoma, MYBNFIB and MYBL1-NFIB fusions in adenoid cystic carcinoma, PLAG1 and HMGA2 in pleomorphic adenoma, ETV6-NTRK3 in secretory carcinoma, NR4A3 rearrangements in acinic cell carcinoma, PRKD1 mutations in polymorphous adenocarcinoma and EWSR1-ATF1 in clear cell carcinoma. This review is a lens for progress made till date in the molecular pathology of salivary gland tumours with a special focus on their role as diagnostic tools and implications on clinical management of the patient as prognostic and predictive markers.

Mucinous cystadenocarcinoma of the breast: a new entity with broad differentials-a case report.

BACKGROUND: Mucinous cystadenocarcinoma is a rare and recently described primary breast cancer with strikingly similar histomorphology to ovarian, pancreatic, and gastrointestinal counterparts. The diagnosis cannot be made until the metastatic lesion is ruled out. CASE PRESENTATION: We are reporting the case of a 65-year-old woman with primary mucinous cystadenocarcinoma of the breast while exploring clinicopathological features and approach to diagnosis. Though the immunohistochemistry panel of CK7, CK20, CDX2, SATB2, PAX8, mammoglobin, and GATA3 plays a crucial role in ruling out metastasis but aberrant CK20 positivity was seen in our case, the final diagnosis was made after a complete radiological workup. We also noted strong membranous HER2-protein expression and HER2-gene amplification by fluorescence in situ hybridization while in literature this tumor is reported to show mainly triple-negative basal type immunophenotype. CONCLUSION: A combined clinic-radio-immunohistochemical approach is essential to make a diagnosis of primary mucinous cystadenocarcinoma.