Variant Of Carcinoma Research Articles

Morphology, immunohistochemistry characteristics, and clinical presentation of microcystic urothelial carcinoma: a series of 10 cases

BackgroundMicrocystic urothelial carcinoma (MUC) is a rare variant of urothelial carcinoma with histological appearances similar to begin lesions. Thus far, approximately 50 cases have been reported. Here, we investigated the clinicopathological features of MUC.MethodsClinical data and paraffin-embedded tissue blocks were collected. Immunohistochemical staining and polymerase chain reaction–Sanger sequencing were performed to detect the phenotype and TERT mutation status of MUC, respectively.ResultsThe mean patient age was 58.8 ± 14.5 years, with a male predominance (8:2). The pathological stage was T1 in one case, T2 in three cases, T3 in four cases, and T4 in two cases. Tumor metastases or death occurred in all five patients who were followed up within 1–3 years. Histological analyses revealed microcystic, tubular, cribriform, and occasionally cord-like structures, which generally lacked interstitial reactions. The lumens were empty, contained eosinophilic secretion, or were filled with mucin. The microcysts/tubules/cribriform patterns were lined by flat, cuboid, signet ring, or columnar types of epithelia. The cuboid, signet ring, and columnar types represented “glandular metaplasia” or glandular differentiation of urothelial carcinoma. Immunohistochemistry analyses revealed distinct co-expression patterns involving the luminal markers FOXA1 and GATA3, as well as the basal markers CK5/6 and CD44. All 10 cases exhibited a luminal phenotype according to the GATA3+/CK14- criterion, whereas nine cases exhibited a luminal phenotype according to the FOXA1+/CK14- criterion. The telomerase reverse transcriptase-C228T mutation was detected in seven cases.ConclusionsMUC is a rare variant with a deceptively benign form of urothelial carcinoma, which is generally identified as a late-stage tumor with a poor prognosis. It exhibits distinct co-expression of luminal and basal markers, along with the TERT-C228T mutation.

Cytological Diagnosis of Follicular Patterned Lesion of Thyroid Nodule and its Follow-up Histopathology

The follicular patterned lesion of thyroid nodules is an exciting topic because it is not clear whether the lesion is benign or malignant. It comprises hyperplastic/adenomatoid nodules, follicular adenoma, follicular carcinoma and follicular variant of papillary carcinoma. The cytological diagnosis of atypia of undetermined significance/Follicular lesion of undetermined significance, follicular neoplasm/suspicious for follicular neoplasm and suspicious for malignancy remains controversial in terms of management. The study aimed to examine the extent of invasion of malignant lesions in follow-up histopathology diagnosed as undetermined lesions cytologically. A total of 256 cases were included in this study; among these, 199 cases were benign lesions, 15 cases were non-diagnostic and 42 cases were diagnosed either of uncertainty for malignancy with cellular atypia or malignancy. Subsequent follow-up resection and histopathology were done with 48 cases (18.75%), which comprises 1 non-diagnostic, 10 benign lesions, 21 atypia of undetermined significance/Follicular lesion of undetermined significance, 7 Follicular neoplasm/Suspicious for a follicular neoplasm, 5 suspicious for malignancy and 4 malignancies. Also, 6 Follicular variant of papillary thyroid carcinoma, 6 classic papillary carcinoma, 5 follicular carcinoma and 1 anaplastic carcinoma were diagnosed in follow-up resection histopathology of 48 cases. Thirty eight cases were of undetermined significance of malignancy with cytological features of the follicular lesion. Four Follicular variant of papillary thyroid carcinoma, 2 follicular carcinoma and 1 papillary carcinoma were diagnosed in 21 resected cases cytologically reported as Atypia of undetermined significance/Follicular lesion of undetermined significance with malignancy risk of 33.33%. Three malignancies in follicular neoplasm/suspicious for a follicular neoplasm with a risk of 42.85% and 4 malignancies in suspicious malignancy group with a risk of 80% were found. The average risk of malignancy of these three undetermined categories was reduced to 24.24% from 42.42% upon reclassification of the Follicular variant of papillary thyroid carcinoma. All the Follicular variants of papillary thyroid carcinoma diagnosed by histopathology were non-invasive regarding lymph node involvement and microvascular or capsular invasion. Mediscope 2023;10(2): 68-77

HER2 Oncogene as Molecular Target in Uterine Serous Carcinoma and Uterine Carcinosarcoma.

Uterine serous carcinoma (USC) and uterine carcinosarcoma (UCS) are two rare histologic variants of uterine carcinoma, with distinct molecular profiles and aggressive metastatic potential. As the effectivity of traditional platinum-based chemotherapy for USC and UCS is low, and there are high rates of resistance and recurrence, the development of novel targeted therapeutics is needed. Human epidermal growth factor receptor 2 (HER2) has proven to be an oncogene of increasing interest in these cancers, as HER2 protein overexpression and/or c-ERBB2 gene amplification ranges from ~30 to 35% in USC, and between ~15 and 20% in UCS. This review summarizes the existing clinical and preclinical evidence, as well as ongoing clinical trials of HER2-targeting therapeutics, and identifies potential areas of further development and inquiry.

Rare cutaneous verrucous carcinoma in the femoral region: a case report

BackgroundVerrucous carcinoma (VC) is a well-differentiated variant of squamous cell carcinoma (SCC) characterized by slow growth and low metastatic potential. Cutaneous verrucous carcinoma (CVC) or papillomatosis cutis carcinoides is the term used for VC in other locations than the oral, anogenital, and plantar regions. This rare tumor has a contradictory “benign” histology, but markedly aggressive clinical behavior. We present this case as background knowledge to corroborate clinical course, diagnosis, histopathology, and treatment options for this infrequent disease. Case DescriptionWe report a verrucous carcinoma on a 79-year-old man’s left thigh. Clinical examination showed a fungating mass with cauliflower-like appearance measuring 5x3x1 cm. Excisional biopsy revealed exo-endophytic proliferation of well-differentiated squamous epithelium invading the dermis with marked hyperkeratosis, parakeratosis, acanthosis, papillomatosis, pushing margins, and minimal cellular atypia (T2N0M0). It was successfully treated by wide local excision, inguinal lymph node dissection, and adjuvant radiotherapy. Follow-up after 1 year showed good wound healing without any loss of function or recurrence. ConclusionCutaneous verrucous carcinoma is a subtype of a low-grade SCC and is not an SCC with a verrucous presentation. Identification of the clinicopathological features is essential to distinguish CVC from its mimics and to make an early diagnosis. Although slow growth and confusing early-stage appearances can lead to delay in diagnosis or to misdiagnosis, this case has not raised many diagnosis problems regarding the cardinal manifestations of CVC. Regardless of any available therapeutic methods, surgical excision with safety margins is still a priority and CVC requires aggressive treatment.

Ultrasound features and risk stratification system in NIFT-P and other follicular patterned thyroid tumors.

NIFT-P (non-invasive follicular thyroid neoplasm with papillary-like nuclear features) is an encapsulated follicular variant of papillary thyroid carcinoma (PTC) with non-aggressive clinical behavior. However, since its diagnosis is exclusively possible after surgery, it represents a clinical challenge. Neck ultrasound (US) shows good sensitivity and specificity in suggesting malignancy in thyroid nodules. However, few information is available about its ability in identifying NIFT-P. The aim of this study was to evaluate the US features of NIFT-P, comparing them with other follicular patterned thyroid tumors, and to test the ability of the main US risk stratification system (RSS) in identifying NIFT-P. We retrospectively evaluated 403 consecutive patients submitted to thyroid surgery, with positive histology for at least one nodule being NIFT-P, follicular variant of PTC (FV-PTC), follicular thyroid carcinoma (FTC) or follicular adenoma (FA). The US features of NIFT-P (n=116), FV-PTC (n=170), FTC (n=76) and FA (n=90) were reported. FV-PTC and FTC more frequently showed irregular margins, presence of calcifications, "taller than wide" shape, and the absence of halo compared to NIFT-P. Furthermore, FTC but also FA were larger and more frequently hypoechoic than NIFT-P. Most cases (77%) showed an indeterminate cytology. Regardless of the US RSS considered, NIFT-P and FA were less frequently classified in the high-suspicious category compared to FV-PTC and FTC. US features of NIFT-P are frequently superimposable to those of nodules with low-suspicious of malignancy. NIFT-P is almost never classified in the high-suspicious category according to the main US RSS. Therefore, although the pre-operative identification of NIFT-P remains a challenge, neck US can be integrated in the algorithm of management of nodules with indeterminate cytology, suggesting a possible conservative approach in those with low-suspicious features.

Clinicopathologic and Immunophenotypic Classification of Invasive Lobular Carcinoma with Histiocytoid Features.

Histiocytoid lobular breast carcinoma is a rare subtype of invasive lobular carcinoma characterized by relatively bland, uniform nuclei, single small eosinophilic nucleolus, and ample granular cytoplasm. These cancers are typically triple negative, show frequent androgen receptor (AR) positivity, and are therefore theorized to represent a variant of apocrine differentiation in invasive lobular carcinoma. Anecdotal evidence suggests that these tumors have excellent outcomes, though some studies suggest a variable clinical outcome. Inclusion criteria included women with a histologic diagnosis of invasive lobular carcinoma with histiocytoid features, regardless of immunohistochemical profile, diagnosed at our institution between 2008 and 2021 with additional tissue still available for ancillary studies. We reviewed patients meeting these criteria and investigated hematoxylin and eosin-stained slides and a panel of immunohistochemical stains (estrogen receptor, progesterone receptor, human epidermal growth factor receptor 2 [HER2], AR, endothelial growth factor receptor, and keratin 5/6), as well as outcomes including survival and metastatic disease. Overall, 12 eligible patients were identified. The classical immunophenotype (triple negative with AR positivity) was noted in 4 out of 12 tumors. The majority of the remaining tumors (7 out of 12) showed a luminal B immunohistochemical profile, while 1 out of 12 was HER2-enriched. No patients in the cohort died from disease-related causes and 2 out of 12 presented with distant metastatic disease during their disease course. Histiocytoid lobular breast carcinoma is a morphologic variant of lobular carcinoma with apocrine features that shows a variable immunohistochemical profile and variable clinical behavior. Further subclassification and stricter diagnostic criteria may be helpful in the distinction between truly indolent tumors and those with more aggressive clinical features.

Desmoplastic small round cell tumor of the liver: diagnosing a rare case on liver biopsy

Desmoplastic small round-cell tumors (DSRCT) frequently develop in the retroperitoneum, pelvis, omentum, and mesentery. Here, we present an unusual case of primary DSRCT in the liver. The patient was an 11-year-old boy with multiple solid masses in the liver parenchyma. The tumor in the needle biopsy had a histology revealing a small round cell morphology and desmoplasia. It shows the immunohistochemical features of DSRCT and documentation of EWSR1-WT1 fusion.A potential diagnostic pitfall is exerted when evaluating liver biopsy, in which DSRCT is a great mimicker and may be easily confused with more common liver malignancies of childhood, such as hepatoblastoma, calcifying nested stromal-epithelial tumor, undifferentiated embryonal sarcoma, and other small round cell tumors, as well as the fibrolamellar variant of hepatocellular carcinoma. This distinction is critical because an accurate therapeutic approach requires a correct diagnosis.

Perianal Cutaneous Spindle Cell Squamous Cell Carcinoma With Myxoid Stroma: Case Report and Literature Review.

Spindle cell squamous cell carcinoma with myxoid stroma is a rare variant of squamous cell carcinoma with sarcomatoid morphology. We report a case of a 75-year-old woman with an ulcerated polypoid cutaneous mass in the perianal area. The patient had a history of clear cell renal cell carcinoma. Microscopy revealed an invasive myxoid spindle cell carcinoma without the classic squamous cell carcinoma component. The immunohistochemical study demonstrated diffuse positive reactions for p63, AE1/3, and CK5/6. The tumor cells were negative for desmin, smooth muscle actin, S100, and CD34. Fluorescent in situ hybridization was negative for EWSR1 gene rearrangement. Follow-up was remarkable for recurrence of tumor in 2 months after complete resection with negative surgical margin. This is the first case report of perianal spindle cell squamous cell carcinoma with myxoid stroma with a literature review of previous case reports from different locations.

Comparative Study of FNAC and Histopathology in Diagnosis of Thyroid Swelling

Background: Neck swelling is a common clinical presentation in ENT practice and it carries significant morbidity and even mortality if not managed properly. Thyroid swelling being the most common type among them. We conducted a study to assess the role of FNAC in diagnosing the nature of thyroid swelling and comparing its result with histopathology finding. The aim and objectives of this study is to observe the correlation between preoperative Fine Needle Aspiration Cytology (FNAC) and post operative histopathology in the diagnosis of thyroid lesions.
 Materials and methods: A cross sectional study was done in the Department of Otolaryngology-Head & Neck Surgery and Department of Pathology, Chittagong Medical College, Chattogram from January 2018 to December 2020. Eighty (80) patients, both male and female of different age groups were included. The selected patients were subjected to clinical examination, routine hematological investigation, thyroid hormone test, USG, thyroid Scan, FNAC and histopathological examinations of the thyroidectomy specimens. Correlation between FNAC and histopathology reports were done in those patients.
 Results: In this study, age range of the patients were 11 years to 70 years. Out of 80 patients of thyroid swelling, the most of the patients 28(35%) were 31-40 years of age groups. out of 80 patients of thyroid swelling, 26(26.25%) were male and 59(73.75%) were female and male female ratio was1:2.81. On FNAC 64(80%) were non neoplastic and 16(20%) were neoplastic. Out of 64(80%) of non neoplastic lesions, 62(77.50%) were nodular goitre and 2(2.5%) were lymphocytic thyroiditis and out of 16(20%) neoplastic thyroid swelling, 2(2.50%) were follicular lesion, 12(15%) were papillary carcinoma, 1(1.25%) was follicular carcinoma and 1(1.25%) was suspicious for malignancy. On histopathology, out of 80 patients of thyroid swelling 60(75%) were non neoplastic and 20(25%) were neoplastic. out of 60(75%) non neoplastic, 59 (73.75%) were nodular, 1(1.25%) was Lymphocytic thyroiditis and out of 20(25%) neoplastic lesions, 3(3.75%) were follicular adenoma,13(16.25%) were papillary carcinoma,3(3.75%) were follicular variant of papillary carcinoma and 1(1.25%) was follicular carcinoma.
 Conclusion: It is concluded from the present study that female are more affected in our region. Non neoplastic lesions of the thyroid were more common (Nodular goitre being the commonest) than neoplastic lesions (Papillary carcinoma being the commonest). FNAC is essential diagnostic tool for thyroid swelling but final diagnosis to rule out thyroid cancer is surgical excision and histopathology.
 Chatt Maa Shi Hosp Med Coll J; Vol.22 (1); January 2023; Page 19-22

Basaloid squamous cell carcinoma: A rare and aggressive cancer of the oral cavity

Basaloid squamous cell carcinoma (BSCC) is an uncommon and severe variant of squamous cell carcinoma (SCC). The tumor arises most commonly in the region of the head-and-neck. It is normally seen in the epiglottis, pyriform fossa, and the base of the tongue. It also occurs less frequently in areas like the palate, buccal mucosa, gingiva and the floor of mouth. Once compared to SCC, BSCC is documented for its aggressiveness in the head-and-neck area, along with its recurrence in local and cervical lymph nodes for its distant metastasis to the lungs. In addition, local lymph nodes are more common in regular recurrence rates. BSCC in the head and neck is more likely to spread to other parts of the body. It has an increased tendency to metastasize when compared with other tumors. We report a rare case of a BSCC arising in the buccal mucosa in a 65-year-old male patient and explain its clinicopathologic characteristics.

Immunohistochemical characterization of clear cell variant of hepatocellular carcinoma in a sheep

The cadaver and viscera of a mature female sheep (Ovis aries) underwent routine abattoir meat inspection. The liver was expanded by an infiltrative neoplastic mass comprising multifocal to coalescing, well-demarcated, pink to white–yellow nodules, up to 25 mm in diameter. An unencapsulated, moderately densely cellular, infiltrative neoplasm was present within the hepatic parenchyma. The neoplastic cells were arranged in solid sheets and acini supported by a moderately fine collagenous vascularized stroma. The neoplastic cells were moderately sized and polygonal, with clearly delineated cell borders and a moderate amount of cytoplasm that was clear or exhibited either globular eosinophilic deposits or fine fibrillar eosinophilic strands. The neoplastic cell nuclei were round and centrally located. The chromatin was lightly stippled and there was frequently a single, prominent, basophilic nucleolus. There were eight mitoses in 10 high-power fields (2.37 mm2). Most of the neoplastic cells had intense cytoplasmic immunolabelling for arginase 1, with frequent concurrent nuclear positivity, and mild to moderately intense punctate cytoplasmic labelling for hepatocyte specific antigen (Hep Par-1). The neoplastic cells did not label with anti-cytokeratin 19 antibody. Based on the histological appearance and the immunolabelling pattern, the neoplasm was diagnosed as the clear cell variant of a hepatocellular carcinoma.

A sneak peek into the diagnostic conundrum of neuroendocrine neoplasms of the breast: An updated review with a brief illustrative case series

Abstract Neuroendocrine neoplasms (NENs) of the breast are uncommon tumours that have been a hitherto poorly and variably defined entity. In the recent fifth Edition World Health Organisation (WHO) classification of breast tumour, NENs are dichotomously classified into neuroendocrine tumours (NETs) and neuroendocrine carcinomas (NECs), mirroring the classification of NENs in other organ systems. Both NETs and NECs are invasive tumours in the breast. However, the clinical significance of neuroendocrine differentiation (NED) in breast cancers, especially in NETs of the breast, is not yet fully understood, and a large overlap appears to exist between breast cancers showing NED and invasive breast carcinoma of no special type (IBC-NST). Although breast NECs show distinct clinical and morphological features and show overlapping molecular features with their counterpart in other organs, especially the high-grade component. Diagnosis of NETs based on the morphological characteristics alone can be challenging; one reason is that breast NETs do not necessarily have the same morphological characteristics as those of NENs arising in other organs and are genetically heterogeneous and harbour molecular alterations that differ from IBC, NST. The keynote changes in the current WHO are the exclusion of other histological subtypes that is, solid papillary carcinoma and a hypercellular variant of mucinous carcinoma which are strong immunohistochemical mimickers of NED and the inclusion of large cell neuroendocrine carcinoma (LCNEC). Thus, the heterogeneity of breast tumours with NED and the changes in their classifications over the years have left many open issues that still need to be resolved. Data regarding the prognostic significance of NED is conflicting and histologic grade and tumour stage remain the main prognostic parameters. Current management of NENs is similar to that of IBC of NST. In this review article, we will summarise the journey of NENs of the breast with an update on the recent WHO classification and discuss their differences from NENs arising in other organs by highlighting an interesting case series depicting their clinical, radiological, histological and molecular features.

Sertoliform endometrioid carcinoma of the right ovary.

Endometrioid carcinomas of the ovary are a subtype of epithelial ovarian tumors, with sertoliform endometrioid carcinomas being a rare variant. We report a case of a previously healthy premenopausal woman presenting with androgenic symptoms in the form of hirsutism and male pattern alopecia. On further testing, she was found to have high levels of luteinizing hormone and total testosterone levels, and imaging revealed a large pelvic abdominal mass in the right ovary. She underwent total hysterectomy with bilateral salpingo-oophorectomy. Microscopy and histopathology confirmed the diagnosis of sertoliform endometrioid carcinoma. Her symptoms improved significantly on follow-up. Androgenic tumors might not be common in premenopausal women; however, it is important to maintain a high level of suspicion in patients presenting with virilizing symptoms especially of rapid progression. Our 47-year-old patient presented with virilizing symptoms that were rapidly progressing, which raises the suspicion of an underlying androgen secreting neoplasm. Sertoliform endometrioid carcinoma (SEC) is an extremely rare variant of endometrioid carcinomas and tend to present at an earlier stage as compared to most endometrioid carcinomas of the ovary. Recognition of SEC in virilizing patients is important as it is a well-differentiated, low-grade malignancy with a good prognosis when confined to the ovary.

The Difference in Clinical Behavior of Gene Fusions Involving RET/PTC Fusions and THADA/IGF2BP3 Fusions in Thyroid Nodules.

Molecular testing has been used as an adjunct to morphological evaluation in the workup of thyroid nodules. This study investigated the impact of two gene fusions, RET/PTC and THADA/IGF2BP3, that have been described as oncogenic events in thyroid neoplasms. We performed a retrospective, single-centered study at a McGill University teaching hospital in Montreal, Canada, from January 2016 to August 2021. We included patients who underwent surgery for thyroid nodules that pre-operatively underwent molecular testing showing either RET/PTC or THADA/IGF2BP3 gene fusion. This study included 697 consecutive operated thyroid nodules assessed using molecular testing, of which five had the RET/PTC fusion and seven had the THADA/IGF2BP3 fusion. Of the five nodules in the RET/PTC group, 100% were malignant and presented as Bethesda V/VI. Eighty percent (4/5) were found to have lymph node metastasis. Twenty percent (1/5) had extrathyroidal extensions. Sixty percent (3/5) were a diffuse sclerosing variant of papillary thyroid carcinoma, and the rest were the classical variant. Of the seven THADA/IGF2BP3 nodules, all presented as Bethesda III/IV and 71.4% (5/7) were malignant based on the final pathology analysis, and 28.6% (2/7) were NIFTP. All the THADA/IGF2BP3 fusion malignancies were a follicular variant of papillary thyroid carcinoma. None had lymph node metastasis or displayed extrathyroidal extensions. RET/PTC nodules presented as Bethesda V/VI and potentially had more aggressive features, whereas THADA/IGF2BP3 nodules presented as Bethesda III/IV and had more indolent behavior. This understanding may allow clinicians to develop more targeted treatment plans, such as the extent of surgery and adjuvant radioactive iodine treatment.

Expression of pY397-FAK and Its miR Regulators Drive Dedifferentiation in the Thyroid Neoplasia Spectrum.

Thyroid carcinomas are growing malignancies worldwide. They encompass several diagnostic categories with varying degrees of dedifferentiation. Focal adhesion kinase is involved in cellular communication and locomotion. It is regulated on a posttranscriptional level by miR-7, miR-135a, and miR-138 and on a posttranslational level by autophosphorylation at Y397 (pY397-FAK). We related regulators of FAK with histologic dedifferentiation, clinicopathological factors, and differential diagnosis in the thyroid neoplasia spectrum. We classified 82 cases into 5 groups with increasing aggressiveness: healthy tissue, follicular and classical variants of papillary thyroid carcinoma (PTC), dedifferentiated PTC, and anaplastic carcinoma. MiRs were analyzed by RT-qPCR. Protein expression of pY397-FAK was analyzed by immunohistochemistry (separately in the membrane, cytoplasm, and nuclear compartment) and Western blot. All three miRs were upregulated in healthy tissue compared to malignant, while pY397-FAK was downregulated. MiRs and pY397-FAK were not mutually correlated. MiR-135a-5p was decreasing while membranous and cytoplasmic pY397-FAK increased with dedifferentiation. Neither miR correlated with clinicopathological factors. MiR-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK discriminated the follicular from the classical variant of PTC. Disturbances of FAK regulation on different levels contribute to neoplastic dedifferentiation. pY397-FAK exerts its oncogenic role in the membrane and cytoplasm. Diagnostically, miRs-135a-5p, miR-138-5p, and membranous and cytoplasmic pY397-FAK differentiated between classical and follicular PTC.

Update on Molecular Diagnostics in Thyroid Pathology: A Review.

Thyroid nodules are quite common, and the determination of a nodule of concern is complex, involving serum testing, radiology and, in some cases, pathological evaluation. For those nodules that raise clinical concern of neoplasia, fine needle aspiration biopsy is the gold standard for evaluation; however, in up to 30% of cases, results are indeterminate for malignancy, and further testing is needed. Advances in molecular testing have shown it to be of benefit for both diagnostic and prognostic purposes, and its use has become an integral part of thyroid cancer management in the United States and in several global nations. After The Cancer Genome Atlas (TCGA) consortium published its molecular landscape of papillary thyroid carcinoma (PTC) and reduced the "black matter" in PTC from 25% to 3.5%, further work ensued to clarify the remaining fraction not neatly attributed to the BRAFV600E-like or RAS-like phenotypes of the TCGA. Over the past decade, commercial molecular platforms have been refined as data accrues, and they increasingly cover most genetic variants of thyroid carcinomas. Molecular reporting focuses on the nodule tested, including related clinical information for that nodule (size of nodule, Bethesda category, etc.). This results in a comprehensive report to physicians that may also include patient-directed, clear language that facilitates conversations about nodule management. In cases of advanced or recurrent disease, molecular testing may become essential for devising an individual therapeutic plan. In this review, we focus on the evolution of integrated molecular testing in thyroid nodules, and how our understanding of tumor genetics, combined with histopathology, is driving the next generation of rational patient management, particularly in the context of emerging small, targetable therapeutics.

Chromophobe-like carcinoma of the thymus: A clinicopathological and immunohistochemical correlation of 5 cases

Five cases of primary thymic carcinoma with distinct histopathological features resembling chromophobe carcinomas are presented. The patients were four men and one woman ranging in age between 43 and 72 years. Clinically, the patients presented with non-specific symptoms of dyspnea and chest pain. Diagnostic imaging revealed the presence of anterior mediastinal masses. All patients underwent complete surgical resection of their tumors via thoracotomy. Grossly, the tumors measured between 4.0 and 5.5 cm in greatest diameter and were ill-defined neoplasms with infiltrative borders; they were light brown in color and had a lobulated surface. Areas of hemorrhage and necrosis were not identified. Histologically, all tumors shared similar histopathological features, mainly the presence of infiltrative tumor islands separated by a fibrocollagenous stroma. At higher magnification, the neoplastic cellular proliferation was composed of medium-sized, round to polygonal cells with eosinophilic or granular cytoplasm and a clear perinuclear cytoplasmic halo, which imparted a chromophobe-like appearance. Nuclear atypia and mitotic activity were identified. Histochemical stains for colloidal iron were negative while immunohistochemical stains for pancytokeratin, cytokeratin 5/6, and p40 were positive in all cases, supporting squamous differentiation in these tumors. Clinical follow-up information was obtained in three patients all of whom died between 3 and 5 years after initial diagnosis, while two patients were lost to follow-up. The cellular characteristics of these tumors represent an unusual variant of thymic carcinoma that may pose a diagnostic challenge in small biopsies and that could be easily confused with other primary or metastatic tumors.

Appendiceal collision tumor presented as acute appendicitis: A dissonant scenario

Renal cell carcinoma arises from the epithelium of the renal tubules and accounts for approximately 3% of adult malignancies. Tumours occur most often in older individuals usually in sixth and seventh decades of life. Bilateral multifocal papillary type of RCC is rare and its presence should prompt the suspicion of some underlying hereditary genetic predisposition thus thorough cytogenetic evaluation and detailed family history could help in finding the etiology. Bilateral RCC could be synchronous or metachronous. We hereby present the autopsy findings of a case of sudden death of a 65 years old male. On histopathological evaluation, both kidneys showed papillary variant of renal cell carcinoma as an incidental finding.

Bilateral multifocal papillary renal cell carcinoma on autopsy: A case report

Renal cell carcinoma arises from the epithelium of the renal tubules and accounts for approximately 3% of adult malignancies. Tumours occur most often in older individuals usually in sixth and seventh decades of life. Bilateral multifocal papillary type of RCC is rare and its presence should prompt the suspicion of some underlying hereditary genetic predisposition thus thorough cytogenetic evaluation and detailed family history could help in finding the etiology. Bilateral RCC could be synchronous or metachronous. We hereby present the autopsy findings of a case of sudden death of a 65 years old male. On histopathological evaluation, both kidneys showed papillary variant of renal cell carcinoma as an incidental finding.

Primary mucinous cystadenocarcinoma of breast with sternal metastasis: A diagnostic challange

The WHO categorizes the breast tumors in various distinct histological types based on cell morphology and architecture. A widely accepted fact that the aggressive nature of the breast cancer can be determined by its histological type, grade, nodal status, and metastasis holds the ground even in the era of immunohistochemistry (IHC) and molecular. An extremely rare variant of primary breast carcinoma belongs to the family of mucin producing carcinoma sharing the same histology as the mucinous cystadenocarcinoma of the ovary and pancreas. The tumour typically occurs in postmenopausal women with a median patient age of 61 years. Due to the rarity of these tumors, there is an extreme paucity of literature on this topic. We report a case of 35 year old female with left breast lump and presternal swelling. Breast lumpectomy and total sternectomy was done and final diagnosis was given as Primary mucinous cystadenocarcinoma with sternal metastasis and Estrogen receptor (ER) and Progesterone receptors (PR) positivity.