Amendments in surgical pathology reports: An 8-year institutional experience.

Surgical pathology reports may undergo revisions broadly categorized as addenda (supplementary information) or amendments (changes to finalized reports). Amendments indicate potential flaws in the diagnostic process and serve as important indicators of vulnerabilities in the histopathology workflow. This study analyzed the frequency and distribution of amendments in surgical pathology reports over 8 years to identify patterns highlighting opportunities for improvement. Surgical biopsies, excisions, and resections were included; cytology and molecular tests were excluded. Amended reports were categorized using previously used taxonomy documented in literature. Defects were classified as misinterpretations, misidentifications, defective specimens, or defective reports. Of 101,355 reports, 155 (0.15 %) were signed out with amendments. The amendment rate was approximately 1-2 cases per 1000 reports annually. Misinterpretations accounted for the majority (52 %) of amended reports, with undercalls (62 %) and overcalls (27 %) being predominant subtypes. Tumor staging was amended in 57 (37 %) cases, with 30 being upstaged and 11 downstaged clinically. The highest number of misinterpretation defects occurred in head and neck (36 %) and breast (21 %) specimens. Misinterpretation defects were present in 53 % of malignant cases versus 42 % of benign cases. In 18 cases, there were significant changes in pathological diagnosis (14 major and 4 minor). A standard taxonomy categorizing report defects is crucial for measuring and improving quality control. Accurate pathology reporting impacts patient care and guides workflow improvements. This taxonomy enables us to track variations and deficiencies in our pathology reporting processes in a reproducible way across the department.

Unmasking the Masquerade: Fine-Needle Aspiration Diagnosis of Dedifferentiated Liposarcoma Clinically Mimicking Lymphoma.

A preoperative diagnosis of dedifferentiated liposarcomas (DDLPS) on fine-needle aspiration cytology (FNAC) is rare with scarce indexed literature. Herein, we describe a case of DDLPS diagnosed on fine needle aspiration which was presumed to be a lymphoma clinically and radiologically.

Lymphoepithelial carcinoma of tongue - Devil in garbs of Hodgkin lymphoma: A case report and review of literature.

Lymphoepithelial carcinoma (LEC) of head and neck region predominantly arises in salivary gland, oral cavity, oropharynx, nasal cavity, paranasal sinuses, and larynx; those arising from tongue are rare. Morphologically, it is a poorly differentiated squamous cell carcinoma, with early regional and distant metastasis. Diagnosis of LEC can sometimes be challenging especially in small biopsy and more so when seen at unusual location. Combination of morphology and immunohistochemistry (IHC) helps the diagnosis. Herein, we report a rare third case of LEC arising from lateral border tongue, diagnosed in a 36-year-old male. The presented case highlights challenges faced during diagnosis in small biopsy. Treatment of LECs comprises of surgery followed by radiotherapy or combined chemoradiation. Though, almost 70% of LEC of oral cavity region present with cervical nodal metastasis, their prognosis remains favorable.

Extranodal follicular dendritic cell sarcoma presenting as colonic mass: A diagnostic and therapeutic challenge.

Folliclular dendritic cell sarcoma (FDCS) is an extremely rare neoplasm originating from folliclular dendritic cells, both nodally and extranodally. Its primary presentation as a large colonic mass is rare and can be misdiagnosed as epithelial tumor/soft tissue tumor both clinically and through histomorphology. Due to its rarity and limited consensus guidelines about its management, it presents as a diagnostic and therapeutic challenge for pathologists and oncologists. However, accurate diagnosis is imperative due to its distinct prognostic and therapeutic implications. Herein we report, two cases of extranodal FDCS of colon with the aim of contributing to the management of this uncommon entity.

Extraskeletal Myxoid Chondrosarcoma of Floor of Mouth-A Rare Case Report and Review of Literature.

Introduction: Chondrosarcomas are rare malignancies of the cartilage and myxoid chondrosarcoma is its variant which commonly occurs in soft tissue of extremities. Extraskeletal chondrosarcoma is a rare malignant neoplasm of bone or soft tissue origin and is characterized by the presence of spindle cells admixed with well differentiated cartilage or chondroid stroma. They are mostly radioresistant tumours and surgical resections with adequate margins is considered as the ideal treatment modality with adjuvant radiotherapy in high grade tumours and add on chemotherapy, in case of presence of poor prognostic factors. Case Report: A 51-year-old diabetic, hypertensive female patient presented to our outpatient department with difficulty in chewing food for a duration of 6 months. On clinical examination, she had an ulceroproliferative growth involving right lower alveolus and floor of mouth. MRI face and neck with contrast showed a 4.1 × 2.9 × 4.5 cm lesion involving right lower alveolus extending to floor of mouth. Biopsy showed features of extraskeletal myxoid chondrosarcoma. She was planned for upfront surgery (Right composite resection with modified radical neck dissection with free fibula flap). Patient was stable post-surgery and was discharged in stable condition. Final histopathology report was high grade myxoid chondrosarcoma. The case was presented in tumour board and the patient was planned for adjuvant radiotherapy. She has been on regular follow up for the past 2 years and shows no signs of recurrence. Conclusion: Extraskeletal myxoid chondrosarcoma of oral cavity is a rare entity and very few cases are reported. It is a malignant neoplasm which is diagnosed with the help of immunohistochemistry. Surgery is the ideal modality of treatment accompanied by adjuvant radiotherapy in cases of high-grade tumours.

Primary Oropharyngeal SMARCA4-Deficient Carcinoma: Expanding the Diagnostic Spectrum in Head and Neck Cancer.

With the advent of molecular immunohistochemistry and next generation sequencing, Switch/sucrose non-fermentable (SWI/SNF) chromatin remodeling complex altered tumors have gained recognition recently. SWI/SNF related, matrix associated, actin dependent regulator of chromatin subfamily B member 1 (SMARCB1) and SMARCA4 are the primary SWI/SNF components altered in several recently described undifferentiated malignancies in head and neck region with predilection for paranasal sinuses in SMARCB1-deficient tumors and nasal cavity in SMARCA4-deficient tumors. However, to the best of our knowledge, SMARCA4-deficient tumors of the oropharynx have not been described. We present an unusual case of SMARCA4-deficient carcinoma of the oropharynx (palatine tonsil) which is the first case in the literature, expanding the topographic distribution of SMARCA4-deficient tumors in the head and neck region and emphasizing the importance of BRG1 as an essential immunohistochemical marker for the diagnosis of this distinct entity.

Diagnostic utility of LMO2 immunohistochemistry in distinguishing T-lymphoblastic leukemia/lymphoma from thymoma.

Distinguishing T-lymphoblastic leukemia/lymphoma (T-ALL/T-LBL) from thymomas (especially B1 or B2 type) can be challenging particularly in limited trucut biopsy material where appreciating architecture is difficult or the background epithelial component does not provide tangible evidence for definite diagnosis. As a pathologist, it is important to accurately diagnose these neoplasms because they have entirely distinct management protocols. Recent studies have reported that LIM Domain Only 2 (LMO2) is expressed in neoplastic lymphoblasts of T-ALL/T-LBL and is absent in thymocytes of normal thymuses or thymomas. An observational study was done to test the sensitivity and specificity of LMO2 in differentiating neoplastic lymphoblasts from thymocytes of thymomas/normal thymuses. Our study showed that LMO2 had sensitivity of 70% and specificity of 100% in diagnosing LBL. None of the thymomas (B1 or B2 type) showed expression of LMO2 in the neoplastic cells. LMO2 is a reliable marker of transformed T-cell precursors and should be routinely included in immunohistochemical panel when evaluating thymic/mediastinal neoplasms.

Comparison of RECIST and iRECIST criteria in patients with advanced lung cancer treated with nivolumab.

Background: Systemic therapy in lung cancer is mainstay of treatment as most patients present in advanced stages, with rising importance of new immunotherapy agents. Purpose: To compare the RECIST 1.1 and the immunotherapy Response Evaluation Criteria in Solid Tumors (iRECISTs) criteria for response assessment in lung cancer patients on immunotherapy. To find the incidence of pseudoprogression and associated imaging patterns. Material and Methods: Retrospective study in 28 patients treated with immunotherapy for advanced metastatic NSCLC. End points were progression-free survival (PFS) and overall survival (OS). Response assessments were separately tabulated according to RECIST 1.1 and iRECIST and classified into dichotomous groups of responders and nonresponders. Agreement in assessments between RECIST 1.0 and iRECIST examined using Cohen kappa (κ) coefficient with 95% confidence intervals. Kaplan-Meier survival analysis was done for PFS and OS. Differences between RECIST 1.1 and iRECIST for both responder and nonresponder were evaluated by the log rank test, Breslow (Generalized Wilcoxon) test, and Tarone-Ware test. Results: Incidence of pseudoprogression was 7% (2/28). The RECIST1.1 and iRECIST were in disagreement in two patients. The agreement between RECIST and iRECIST was almost perfect. The PFS and the OS are significantly longer in duration for responders in comparison to nonresponders for both RECIST and iRECIST and the difference between two assessment criteria is not significant. Conclusion: Although iRECIST aims to monitor treatment more precisely than conventional response criteria, this must be weighed against how infrequent pseudoprogression is and the cost of this therapy, both financially and in the potential delay in changing to a more effective treatment.

Primary pulmonary NUT midline carcinoma: An elusive and a rare diagnostic entity.

Nuclear protein in testis (NUT) midline carcinoma is a poorly differentiated tumor, is more common in midline anatomic sites, and involves young adults and children mainly. Primary pulmonary NUT midline carcinoma (NMC) is a rare and poorly defined entity in the prevailing literature. Being a highly aggressive and fatal neoplasm, it gets incumbent for the oncologists and the pathologists to be aware of this entity as it holds distinct management protocol and prognosis. Currently, BET inhibitors (BETi) and histone deactylase inhibitors have shown promising results as targeted therapies in clinical trials in head and neck NMC. We present a case report of NMC of primary pulmonary location in a young male with widespread bony metastasis.

Metastatic choriocarcinoma of the kidney in the absence of existing primary uterine tumor: A rare presentation.

Gestational choriocarcinomas are malignant neoplasms generally arising in the uterus in women of childbearing age. These are aggressive tumors with a high incidence of metastasis to vascular organs such as the lung, liver, and brain. Renal metastasis is extremely rare with low incidence rate and very few cases have been reported in literature. Hereby, we report a rare case of metastatic choriocarcinoma to the kidney in a 29-year-old female 10 years after resection of a hydatidiform mole. The histopathological diagnosis was made on a nephrectomy specimen. Pelvic and abdominal scan did not show any abnormal radiological findings. She was started on first-line chemotherapy and showed a complete response. In conclusion, gestational or primary nongestational choriocarcinomas should always be considered as a differential diagnosis in young females of reproductive age group presenting with flank abdominal pain, unexplained hematuria, and atypical renal tumor histology.

A Case Series of Neurolymphomatosis: Role of Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography Scan Reiterated.

Neurolymphomatosis is rarely encountered in high-grade lymphomas. In this case series, we retrospectively analyzed six neurolymphomatosis cases to look for possible risk factors, common and uncommon presentations, and the lessons learned. Neuropathic pain was the most common symptom with mono or polyradiculopathy in this series. However, all lymphomatous infiltrated nerves diagnosed on fluorodeoxyglucose positron emission tomography-computed tomography (FDG PET/CT) were not symptomatic. The lumbar, brachial plexus, and trigeminal nerve were the most common sites and were depicted well on FDG PET/CT. Magnetic resonance imaging (MRI) of the brain better delineates cranial nerves and meningeal involvement. Cerebrospinal fluid flow cytometry was normal until meninges were involved. FDG PET/CT incrementally evaluated extra-neural disease sites, thus helping in deciding biopsy sites and further management. We concluded that a whole-body FDG PET/CT including limbs with MRI brain was the appropriate investigation for evaluating suspected neurolymphomatosis in advanced-stage diffuse large B-cell lymphoma.

Application of lean methodology to frozen section workflow - An audit of present practices at a single large oncology center.

AIM: We conducted a pilot study to analyze the frozen section workflow in the histopathology department and to construct a future state map using Lean management for a better efficiency. METHOD: We analyzed the current state of frozen section workflow in our department, from receipt of the specimen to delivery of slides to the pathologist to communication of report to the surgeon by using value-stream mapping and spaghetti diagram. Further, with the help of the fishbone diagram and Pareto's chart, root cause analysis was done, and a future state map was created with help of a spaghetti diagram to eliminate the non-value-added steps. RESULTS: Our current value-stream map identified a total specimen processing time of 3393 min of which 2880 min were value-added, translating to a process cycle efficiency of 84.88 %. Also, with the help of tools of lean management we constructed a future state map to improve process cycle efficiency. CONCLUSION: In this study, we have attempted to use a few tools of lean management systems and suggested ways for continuous improvements that can be successfully implemented in histopathology laboratories.

Correlation NKX2.2 IHC and EWSR1 break-apart FISH in the diagnosis of Ewing sarcoma: Can combined NKX2.2 and CD99 immunoexpression obviate or minimize the need of FISH testing? First assessment study from Indian tertiary cancer care center.

Context: Ewing sarcoma (ES) are malignant small round cell tumors (MSRCT) characterized by rearrangements of EWSR1 gene. Although gold standard for diagnosis is detection of specific fusion genes by molecular testing, these ancillary tests are costly and only available in limited number of settings. There is a persuasive evidence for reliability of NKX2.2 immunohistochemistry (IHC) as a surrogate marker for EWSR1 gene rearrangement in ES. Aims: The aim of this study is to correlate the NKX2.2 immuno-expression with genetically confirmed ES cases and also to assess the reliability and accuracy of NKX2.2 along with combined positivity of NXX2.2 and CD99 in diagnosing ES and differentiating it from other relevant histological mimics. Settings and Design: The present study is a retrospective study conducted over a period of 6-year duration in a tertiary cancer care center. Methods and Material: We evaluated NKX2.2 immunoexpression in 35 genetically confirmed cases of ES and also in pertaining differential entities (n = 58) of ES including rhabdomyosarcoma (n = 20), lymphoblastic lymphoma (n = 14), Wilms tumor (n = 10), poorly differentiated synovial sarcoma (n = 4), small-cell osteosarcoma (n = 4), neuroblastoma (n = 5), and mesenchymal chondrosarcoma (n = 1). CD99 was performed in the category of MSRCTs showing NKX2.2 positivity to evaluate combined specificity for the diagnosis of ES. Results: Of the 35 genetically confirmed cases of ES, 29 cases (83%) showed NKX2.2-positive expression (83% sensitivity). Compared to ES, NKX2.2 was positive in only 05% cases (3/58 cases) of non-ES MSRCT. Only two of five cases of neuroblastomas and one case of mesenchymal chondrosarcoma showed NKX2.2 positivity. CD99 positivity was seen in 100% of ES and in the single case of mesenchymal chondrosarcoma. All five cases (100%) of neuroblastoma were negative for CD99. Conclusions: The presented study, which is the first from an Indian oncology center, showed NKX2.2 IHC is quite reliable in diagnosis of ES in the right clinicopathological context. With remarkable sensitivity and specificity of NKX2.2 IHC for diagnosis of ES, we propose that combined positivity of CD99 and NKX2.2 IHC can obviate or minimize the need of EWSR1 gene rearrangement molecular testing for diagnosis of ES.

Myeloid sarcoma presenting as nasopharyngeal mass: A rare clinicopathological scenario.

Myeloid sarcoma (MS) is considered as an extramedullary manifestation of acute myeloid leukemia (AML) with or without concurrent AML. It can present at any age and any site, however, nasopharynx being an extremely rare site of manifestation. MS may precede AML by weeks, months or years, thereby necessitating an early diagnosis and timely intervention and treatment. We report a case of MS in a young female who presented with nasal obstruction and epistaxis for 3 months. The present case also highlights the significance of judicious use of immunohistochemistry panel while dealing with a hematolymphoid neoplasm devoid of expression of B-cell or T cell specific markers in head and neck region.

Macroscopic Extranodal Extension In Oral Squamous Cell Carcinoma-A Subgroup With Poor Survival.

BACKGROUND: Oral cancer portends a significant cause of morbidity and mortality worldwide. Cervical lymph node metastasis with extranodal extension (ENE) is associated with a poor prognosis. There has been accumulating evidence regarding the extent of ENE to be associated with prognosis and survival. AIM: This observational study was performed to analyze the prognostic implication of macroscopic and microscopic ENE in metastatic cervical lymph nodes of oral cavity cancer patients. METHODS: A total of 92 oral cavity cancer patients with pathologically detected ENE were included in this study. Both the groups (macroscopic and microscopic ENE) were compared in terms of overall survival and disease-free survival by using Kaplan -Meier. The pattern of failure was determined by Fischer's exact test. Univariate and multivariate analyses were calculated to determine the significant risk factors of death. RESULTS: The 2 years of disease-free survival and overall survival rates for the whole cohort were 51.2% and 53.9% respectively. The 2-year survival rate for the microscopic group (≤2 mm) and macroscopic (>2 mm) was 72.6% and 0% respectively, while the distal failure rate in microscopic ENE group and macroscopic ENE group was 22.22% and 44.83% respectively (p-value = 0.026). CONCLUSIONS: Macroscopic ENE (>2 mm) in oral cavity squamous cell cancer represents an aggressive entity with early regional and distant failure as compared to microscopic ENE (≤2 mm). Thus, macroscopic ENE (>2 mm) warrants a distinct subgroup with special consideration for intensification of treatment. LEVEL OF EVIDENCE: 3 Laryngoscope, 133:588-593, 2023.

PD-L1 expression in muscle invasive urothelial carcinoma: Comparison of SP142 and SP263 assay.

Introduction: High-grade urothelial carcinoma has a different molecular pathway than superficial low grade urothelial carcinoma, and is characterized by genomic instability. The high tumor mutation burden leads to neoantigen formation, evoking an immune response. The immune response has been keenly studied in last two decades and programmed death ligand-1 (PDL-1) has emerged as acceptable immunohistochemical marker for assessment of response to therapy, prognostication and patient selection for immunotherapy. The targeting of PD-1 and PDL-1 by checkpoint inhibitors (CPIs) is an attractive strategy to unblock the inhibitor and induce cytotoxic cell death. However, the presence of complementary and companion diagnostic testing with multiple PDL-1 assays and platforms for various CPIs make a diagnostic quagmire. Thus, it is the need of hour to harmonize these assays. In this undertaken study we evaluated the concordance in PD-L1 expression between the two PD-L1 clones: SP263 and SP142, in treatment naïve muscle invasive bladder cancer (MIBC). Methods: We evaluated Ventana PD-L1 "SP263 and SP142" qualitative immunohistochemical assay using rabbit monoclonal anti-PD-L1 clones in evaluation of PDL-1 immunoexpression on Ventana autostainer platform. The study includes 30 muscle invasive urothelial carcinomas, with 10 of 30 having nodal metastasis. Results: SP263 assay was statistically more sensitive than SP142 for tumor cell (TC) scoring (P = 0.0009), whereas SP142 was more sensitive for immune cell (IC) scoring (P = 0.0067). There was no statistical significant discordance for TC or IC scoring between primary tumor and metastatic lymph node. Conclusion: PD-L1 testing status can be done on both primary tumor and metastatic site, however in metachronous metastatic setting, testing on recent metastatic site should be preferred. The harmonization of immunoexpression between 2 PD-L1 clones could not be achieved.

Molecular stratification of high-grade urothelial carcinoma by immunohistochemistry with its histomorphological and clinical correlation.

Introduction: Urothelial carcinoma poses a significant cause of morbidity and mortality. The recent classification of Tumors of Urinary System by World Health Organization fourth edition) has elucidated its molecular subtypes and its associated prognostic significance. Methods: We used immunohistochemistry marker expression (CK5/6, CK20, CD44, EGFR) as a surrogate marker, to stratify 150 cases of high-grade urothelial carcinoma into the intrinsic molecular subtypes. A correlation was also done with immunohistochemical markers p53, p21, E-cadherin and Ki-67. Results: On subtyping, 47.3% cases were basal, 42.7% luminal and 10% remained unclassified. We did not find GATA3 useful for molecular stratification in our study. Muscle invasion was seen in 59% of basal and 31% of luminal subtype (P = 0.016). Squamous differentiation was most commonly associated with basal subtype (P < 0.001). EGFR expression was seen in 62% of basal and 38% of luminal subtype (P = 0.014), and thus can be used as an additional marker for molecular stratification. Overexpression of p53 was seen in 64% cases of muscle invasive and 36% of non-muscle invasive high-grade carcinomas (P < 0.0001). An inverse relationship was observed between p53 and p21 immunoexpression (r = -0.494) (P < .0001). The overall survival at 1- and 2-year interval was more in the luminal subtype, suggesting an early mortality in basal group, (P = 0.827), and at 6 years both the groups had almost similar results. Conclusion: High-grade urothelial carcinoma is challenging in terms of therapeutic strategy. Increased understanding of underlying molecular basis helps identifying targetable treatment options, and newer biomarkers will enhance predictive and prognostic stratification.