International Journal of Surgical Pathology

Background. Gastric intestinal metaplasia increases the risk of gastric cancer by nine times. Although attempts are made to diagnose it using endoscopic methods, the final diagnosis is established by examining and reporting biopsy samples. Although there are studies in the literature that do not recommend routine special staining, many laboratories routinely perform alcian blue/periodic acid Schiffs (AB/PAS) staining, in addition to hematoxylin and eosin (H&E) staining. In this study, we examined the need for performing routine special staining. Methods. Seven hundred forty-one consecutive gastric biopsies obtained from the archive of our laboratory in 2019 were included in the study. One day after evaluating the cases using H&E, they were evaluated with AB/PAS without examining the H&E results. Result. All of the intestinal metaplasia lesions detected in H&E were observed with AB/PAS. However, we missed 14 (13.73%) of 102 intestinal metaplasia lesions with H&E that we detected using AB/PAS. We found the sensitivity and specificity of H&E in detecting intestinal metaplasia were 86.3% and 99.7%, respectively. When we retrospectively examined the 14 missed lesions in H&E staining, we could observe intestinal metaplasia in six biopsies, but it was not possible in eight (7.8%). Conclusion. Considering that gastric intestinal metaplasia is a precancerous lesion, we think that this ratio (13.73%) is high and that the number of malignancies can be reduced with a low-cost special stain. In this context, we advocate and recommend routinely performing inexpensive special staining such as AB/PAS to detect intestinal metaplasia in all gastric biopsies.

Background. Fibroadenoma (FA) and benign phyllodes tumor (PT) of the breast often have similar appearances on imaging. While an exact diagnosis of biopsy specimens is required to choose adequate treatment, including surgical procedures, it is sometimes difficult to pathologically differentiate these 2 tumors due to histological resemblances. To elucidate markers for distinguishing FA from benign PT, we analyzed clinical samples immunohistochemically. Methods. We retrospectively investigated 80 breast fibroepithelial lesions. As a discovery set, 60 surgical excision samples (30 FA and 30 benign PT) were examined. Twenty biopsy samples (10 FA and 10 benign PT) were examined as a validation set. To determine targets for immunohistochemistry, we first tested some proteins based on previous reports. As a result, Ki67 was chosen for differentiating FA and PT; thus further examinations were conducted with this protein. Results. Among the proteins examined, stromal Ki67 was significantly higher in PT than in FA. Benign PT had significantly higher stromal Ki67 expression both at random and at hotspots (p < .001 and <.001, respectively). The receiver operating characteristic curve analysis identified 3.5% and 8.5% (at random spots and hotspots, respectively) as the optimal cutoff values of stromal Ki67 for distinguishing between these 2 tumors. In the validation cohort employing needle biopsy specimens, we confirmed that these 2 cutoff values properly classified these 2 tumors (p = .043 and .029, respectively). Conclusion.We revealed that stromal Ki67 might be a potential marker for distinguishing FA from benign PT.

Introduction. Small cell carcinoma can arise from various sites. Herein, we analyze the ability of 2 thyroid transcription factor-1 (TTF-1) antibodies (SPT24 and 8G7G3/1) to separate pulmonary from nonpulmonary small cell carcinoma. Materials and Methods. We analyzed 26 pulmonary and 83 nonpulmonary small cell carcinomas, and 14 Merkel cell carcinomas. Each tumor was stained with SPT24 and 8G7G3/1. Extent of nuclear staining was scored as diffuse (>50%), focal (11%-50%), rare (1%-10%), or negative (<1%). Results. All pulmonary small cell carcinomas were positive for SPT24 and 8G7G3/1. Four Merkel cell carcinomas (29%) were positive for SPT24 (ranging from rare-to-diffuse), while 2 (14%) showed rare expression with 8G7G3/1. For nonpulmonary small cell carcinomas, 69 (83%) were positive for SPT24 and 40 (48%) were positive for 8G7G3/1. For SPT24 positive tumors, the extent of 8G7G3/1 expression was equal in 17 (25%) and less in 52 tumors (75%), including 29 (42%) that were negative for 8G7G3/1. No nonpulmonary small cell carcinoma had more staining with 8G7G3/1 compared to SPT24. The differences in staining between 8G7G3/1 and SPT24 in the nonpulmonary cohort were statistically significant (P < 0.0001) with no significant difference between primary and metastatic lesions for 8G7G3/1 (P  =  0.66) or SPT24 (P  =  0.77). Conclusion. Most pulmonary small cell carcinomas are diffusely positive for both SPT24 and 8G7G3/1, whereas most nonpulmonary small cell carcinomas exhibit focal-to-no staining with 8G7G3/1 and significantly less staining with 8G7G3/1 compared to SPT24. However, these trends are not absolute and should be interpreted in conjunction with clinical and radiological findings.

Introduction. Triple negative breast carcinomas are characterized by a lack of hormone receptor and HER2 expression and inconsistent expression of breast-specific immunohistochemical markers. The expression of many site-specific markers in these tumors is largely unknown. The objective of the study was to examine the expression of widely used immunohistochemical markers on a large cohort of triple negative breast cancer. Methods. Sections from tissue microarrays were stained with 47 markers using routine protocols. Most markers were scored using a modified Allred method. ATRX, BAP1, SMAD4, e-cadherin, and beta-catenin were scored as retained or lost. Mammaglobin was considered positive if there was at least moderate intensity staining in any tumor cells. P16 was scored as overexpressed or not overexpressed; p53 was scored as wildtype, overexpressed, null, or cytoplasmic. Results. The cohort consisted of 639 tumors including 601 primary and 32 metastases. Overall, 96% expressed GATA3, mammaglobin, and/or SOX10 while 97% of no special type tumors expressed this panel. Carcinoma of apocrine differentiation demonstrated an AR positive, SOX10 negative, K5 negative/focal immunophenotype. PAX8 (SP348), WT1, Napsin A, and TTF1 (8G7G3/1) were never or rarely expressed while CA9, CDX2, NKX3.1, SATB2 (SATBA410), synaptophysin, and vimentin were variably expressed. Conclusions. Almost all TNBC express at least 1 of the 3 IHC markers: GATA3, mammaglobin, and/or SOX10. Carcinoma of apocrine differentiation is characterized by an AR positive, SOX10 negative, K5 negative or focal immunophenotype. Cautious interpretation of so-called site-specific markers, with knowledge of antibody clones, is required in excluding the diagnosis of triple negative breast cancer.

Background. Dermatopathic lymphadenopathy is a well-defined histopathological entity with an underestimated prevalence in the general population. Objective. The present study was conducted to analyze the characteristics of histologically diagnosed cases of dermatopathic lymphadenopathy at our unit. We also aimed to investigate any association between the clinical features of the patients and the histological findings. Methods. A total of 39 lymph node samples from 39 patients diagnosed with dermatopathic lymphadenopathy were included in this prospective cohort study. Results. Thirty-four (87%) patients had a dermatological disorder. The presence of paracortical eosinophils were significantly higher in patients with dermatological disorders (P = .001), while the presence of dilated sinuses was significantly more common in patients without a dermatological disorder (P = .035). The presence of dilated sinuses and medullary histiocytes were significantly more common in patients with lower body surface area involvement of the disease compared to the ones with a higher body surface area (P = .003, P = .034; respectively). Conclusion. Most of the patients included in the study had one of a broad spectrum of undiagnosed dermatological disorders. The clinical significance of the relation between histological and clinical findings in dermatopathic lymphadenopathy remains to be explained. Dermatopathic lymphadenopathy should always be considered in differential diagnoses of patients with persistent lymph node enlargement even when absolute dermatological disorders are not present. Since various skin disorders may be the cause of lymphadenopathy, performing a full-body examination before lymph node excision might prevent unneccessary procedures.

Increasing survivorship in kidney cancer patients has shifted treatment strategies to optimize renal function preservation. In 2010, the College of American Pathologists (CAP) updated their synoptic reporting guidelines for tumor nephrectomies to require evaluation of the nonneoplastic kidney parenchyma. We conducted this study to understand current practice behaviors regarding the evaluation of the nonneoplastic kidney parenchyma in tumor nephrectomy specimens. We emailed a 14-item multiple-choice survey to members of the Renal Pathology Society and Genitourinary Pathology Society. We also emailed a 12-item survey to program and associate program directors of American pathology residencies to assess the current state of renal pathology education. Ninety-eight genitourinary and 104 renal pathologists responded to the survey on the nonneoplastic kidney parenchyma. Ninety-five percent of respondents who examine tumor nephrectomies reported evaluating the nonneoplastic kidney parenchyma. Seventy-five percent of genitourinary pathologists and 67% of renal pathologists use synoptic reporting, and 81% use the CAP protocol. Thirty-nine percent of respondents report always contacting the clinician when they find evidence of medical renal disease. Forty-two program leaders responded to our renal pathology education survey, and 64% of them have a mandatory renal pathology rotation that on average lasts about 2 to 4 weeks. The majority of pathologists examine the nonneoplastic kidney parenchyma of tumor nephrectomies and frequently report incidences of new medical renal disease directly to clinicians, but there remains room for improvement and educational gaps during residency training. Further efforts to standardize both this evaluation and renal pathology education will improve patient care.

Renal cell carcinoma (RCC) is occasionally associated with vena cava involvement. Despite recent advances in therapeutic modalities, the 5-year survival in this population continues to be poor. Therefore, further studies are required to better characterize this patient population, especially from the clinicopathologic standpoint. A comprehensive review of patients with RCC and vena cava involvement managed at our institution from 2014 to 2022 was performed. Multiple clinicopathologic parameters including follow-up were obtained. A total of 114 patients were identified. The mean patient age was 63 years (range: 30-84 years). The cohort consisted of 78/114 (68%) males and 36/114 (32%) females. The mean primary tumor size (excluding tumor thrombus) was 11 cm. The majority of tumors (104/114, 91%) were unifocal. Tumor stages were categorized as follows: pT3b (51/114, 44%), pT3c (52/114, 46%), and pT4 (11/114, 10%). Most of the tumors were clear cell RCC 89/114 (78%), although other more aggressive RCC subtypes were also present. Most tumors were WHO/ISUP grade 3 (44/114, 39%) or 4 (67/114, 59%) with sarcomatoid differentiation present in 39/67 (58%). Necrosis was present in 94/114 (82%) tumors. Twenty-three of 114 (20%) tumors were categorized as pM1 and the ipsilateral adrenal gland was the most common site of metastasis. Of the 91 patients categorized as pM, not applicable at nephrectomy, 42/91 (46%) subsequently developed metastasis, most frequently to the lung. Of all patients, only 16/114 (14%) had positive vascular margins and 7/114 (6%) had positive soft tissue margins despite having very advanced disease and a subset considered inoperable at other centers.

Introduction. Cardiac amyloidosis is a lethal disease, the incidence of which is increasing every year. Early diagnosis and treatment are the keys to reducing the mortality of this disease. Methods. Relevant English literature published in Embase, PubMed, Cochrane Library, and Web of Science were searched until December 1, 2022. Meta-analysis was performed with Stata 17.0 software. Results. A total of 1060 patients with 5 articles were included in this study. The sensitivity of abdominal fat aspiration biopsy for the diagnosis of cardiac amyloidosis was 0.66 (0.48–0.84) and the sensitivity for light chain amyloidosis cardiomyopathy and transthyretin amyloidosis cardiomyopathy was 0.90 (0.80–0.97) and 0.39 (0.18–0.60), respectively. Conclusion. Abdominal fat aspiration biopsy has high sensitivity and clinical value in the diagnosis of light chain amyloidosis cardiomyopathy, whereas there are limitations in the diagnosis of transthyretin amyloidosis cardiomyopathy.

Background. Tumor budding is a poor prognostic factor in colorectal adenocarcinoma, but the underlying mechanism remains unclear. Interleukin-6 (IL6) is one of the main cytokines produced by cancer-associated fibroblasts. IL6 is linked with cancer progression and poor prognosis by activating cancer cells and modifying the cancer microenvironment. However, little is known about the expression of IL6 in tumor budding and its association with tumor budding in colorectal adenocarcinoma. Methods. The clinicopathological and prognostic significance of IL6 in tumor budding was examined using a tissue microarray consisting of 36 patient samples of tumor budding in colorectal adenocarcinoma. IL6 mRNA was detected by RNAscope. Patients were stratified into negative and positive IL6 expression groups. Results. IL6 expression was overwhelmingly observed in cancer stroma but was negligible in cancer cells. Tumor budding grade was higher in the IL6-positive group in cancer stroma than in the IL6-negative group (P = .0161), while the IL6-positive group significantly exhibited the epithelial–mesenchymal transition phenotype compared with the IL6-negative group in cancer stroma (P = .0301). There was no significant difference in overall survival between colorectal adenocarcinoma patients in the IL6-positive and -negative groups in cancer stroma. Conclusion. Tumor budding may be affected by IL6 expression, and IL6 expression in cancer stroma at tumor budding may be an important prognostic marker.

The differential diagnosis for oncocytic renal tumors spans the spectrum from benign entities to more aggressive renal cell carcinomas (RCC). Recent work has characterized a provisional renal oncocytic neoplasm, namely the low-grade oncocytic tumor (LOT), which demonstrates overlapping morphologic features with oncocytoma and chromophobe RCC, but also has a unique immunoprofile (ie, diffusely positive for KRT7, negative for KIT) and a high rate (80% to 100%) of mTOR pathway gene alterations. Given the diagnostic overlap among oncocytic tumors, we looked for concordance between mTOR pathway mutations and LOT. Thirty low-grade renal oncocytic neoplasms underwent histologic review and immunohistochemistry for KRT7 and KIT. Tumors were classified as “determinate” (eg, LOT) for tumors with solid, nested or vaguely tubular growth and diffuse KRT7 staining and negative KIT, or “indeterminate” if the morphology and/or immunostains did not fully support a definitive LOT diagnosis. Next-generation sequencing was performed without any knowledge of the diagnoses, and identified mTOR pathway mutations in 80% (12/15) of the determinate tumors, compared with 7% (1/15) in the indeterminate group. One determinate tumor was reclassified as papillary RCC (MTOR mutation negative) and 6 indeterminate tumors were confirmed to be oncocytoma (N = 4), clear cell RCC or papillary RCC with reverse polarity, respectively. Overall, integration of morphology, immunohistochemistry, and molecular data enabled a final definitive diagnosis for 70% of tumors (21 of the total 30), with a high concordance (93%) for LOT specifically in the determinate group; the remaining 9 tumors (30%) were classified as renal oncocytic neoplasm, not otherwise specified.

Deficiency of fumarate hydratase (FH) protein expression in uterine corpus leiomyomas may be attributable to either germline or somatic mutations of the FH gene, the former being definitional for the hereditary leiomyomatosis and renal cell cancer syndrome. The authors assess whether, using previously reported FH-associated morphologic features, FH protein-deficient uterine corpus leiomyomas associated with a pathogenic germline mutations of the FH gene (group 1) are distinguishable from FH protein-deficient uterine corpus leiomyomas without such mutations (and whose FH protein loss is presumed to be attributable to somatic/epigenetic inactivation or other unknown phenomena: group 2). Groups 1 and 2 were compared regarding a variety of clinicopathologic features, including 7 core “FH-associated” tumoral morphologic features: staghorn vasculature; alveolar-type edema; bizarre nuclei; chain-like tumor nuclei; hyaline cytoplasmic globules; prominent nucleoli, intranuclear inclusions, and perinucleolar halos; and prominent eosinophilic/fibrillary cytoplasm. Among 2418 patients diagnosed with uterine corpus leiomyoma during the study period, FH-associated morphologic features were reported in 1.5% (37 patients), and FH immunohistochemistry was performed in 29 (1.19%). Fourteen (48.27%) of the 29 patients showed FH protein deficiency by immunohistochemistry. Twelve patients underwent germline testing, of which 8 (66.7%) were classified as group 1 and 4 (33.3%) as group 2. FH protein-deficient tumors were larger (10.44 vs 4.08 cm, P  =  0.01) and associated with younger patients (42.05 vs 47.97, P  =  0.004) than 370 randomly selected uterine leiomyoma controls. Groups 1 and 2 showed no significant differences in patient age and tumor size. In group 1 tumors, the FH-associated morphologic features were generally present diffusely; all group 1 tumors displayed ≥5 FH-associated features, whereas all group 2 tumors displayed <5 FH-associated features (means 6.5  ±  0.53 vs 3.5  ±  1.00, P < 0.001). Notably, eosinophilic/fibrillary cytoplasm and alveolar-type edema were each significantly more prevalent in group 1 tumors than group 2 tumors (P  =  0.018 for both). No single morphologic feature was found to be completely sensitive and specific in making the distinction between group 1 and 2 tumors. Our findings suggest that groups 1 and 2 are unlikely to be morphologically distinguishable by individual morphologic features. Whether there is a combination of features that can reliably make this distinction is unclear and will require additional studies with larger cohorts.

Undifferentiated carcinoma of the esophagus is an entity that is included in WHO classification of digestive systems fifth edition (2018). The definition of this entity is a malignant esophageal epithelial tumor that lacks definite microscopic features of squamous, glandular, or neuroendocrine differentiation. It is a challenging diagnosis to make due to lack of diagnostic criteria. We report a case from a 45 years old man with a mass in the lower third of esophagus. Biopsy showed an epitheloid neoplasm with sheet like growth pattern and no glandular formation. The tumor cells had prominent nucleoli and indistinct cell borders. There were occasional rhabdoid cells. By immunostains, tumor cells were focally positive for pankeratin, keratin 7, synaptophysin, negative for CDX2 and p40, INSM1, chromogranin, and CD56. Background intestinal metaplasia (Barrett esophagus) was present. Next generation sequencing of the tumor revealed SMARCA4 deep deletion. The tumor showed loss of SMARCA4 by immunostain. This case demonstrates that undifferentiated carcinoma of the esophagus with SMARCA4 deletion can express synaptophysin. Awareness of this entity is important for the correct classification of this tumor.

Primary angiosarcoma of the breast is very rare and difficult to pathologically diagnose especially on core needle biopsy. Only 11 cases of breast primary angiosarcoma diagnosed on core needle biopsy have been reported in English literature of last 5 years. We reported a case of primary angiosarcoma of the breast diagnosed on core needle biopsy and summarized the useful morphological clues in literature which prompted the diagnosis of angiosarcoma. A 50-year-old woman presented with a palpable mass in her left breast for a year. She never received breast surgery or radiotherapy before. Microscopically, the core needle biopsy specimen displayed interanastomosing vascular spaces that dissected through the mammary stroma and adipose tissue. The vascular channels were mostly lined by a single layer of endothelial cells with a mild degree of nuclear atypia, whereas focally, the endothelia were multilayered, with tufting and formation of glomerulus-like structures. CD31, CD34, and ERG immunochemical stain highlighted the endothelial cells lining on the vascular spaces. The Ki67 index was about 10%, and MYC was negative. Primary angiosarcomas have significant overlaps of morphological features with benign and borderline vascular lesions. Anastomosing vascular spaces, cytologic atypia, endothelial mitotic activity, infiltration of glandular parenchyma, elevated Ki-67, and high cellularity are all useful clues to diagnose angiosarcomas. Among them, anastomosing vascular spaces with infiltrated growth pattern especially invasion into the breast intralobular stroma and adipose tissue was the most common character of angiosarcomas which alert the possibility of malignancy in core needle biopsy. However, an accurate diagnosis demands integration of various histological clues and multidisciplinary discussion.

Malignant gastrointestinal neuroectodermal tumor (GNET), also referred to as clear cell sarcoma-like tumor of the GI tract is a rare mesenchymal tumor of the gastrointestinal tract. It has to be distinguished from various mimickers including gastrointestinal stromal tumor (GIST) due to its aggressive course and different natural history and therapeutic approach. Here we report a case of GNET arising in the small intestine with aberrant DOG1 expression posing a diagnostic challenge. In this context, the combination of clinical, histomorphological, immunohistochemical, and molecular features helped to establish a proper diagnosis.

Melanotic neuroectodermal tumor of infancy (MNTI) is a rare, benign neoplasm of neural crest origin that predominantly involves the craniofacial region, involvement of the epididymis being extremely rare, with about 30 cases reported. We report an unusual case of a 5-month-old male with MNTI in the epididymis. The patient underwent orchiectomy. Half a year later, there was no sign of recurrence. Whether preoperative examination or intraoperative frozen examination, the tumor may easily be misdiagnosed as malignancy. Melanotic neuroectodermal tumor of infancy should be included in differential diagnosis in infants presenting with fast-growing scrotal swelling.

Peutz-Jeghers syndrome (PJS) is associated with female genital lesions, such as cervical gastric-type adenocarcinoma and lobular endocervical glandular hyperplasia (LEGH). However, ovarian mucinous borderline tumors (OMBT) with atypical LEGH-like histology have not been described. The patient was a 60-year-old female with PJS clinically diagnosed at 23 years old with gastrointestinal polyposis. Abdominal distension was noted, and computed tomography scan revealed bilateral breast masses, multiple lung nodules, and a multicystic ovarian tumor. A needle biopsy revealed invasive ductal carcinoma of the breast. For the ovarian tumor, simple hysterectomy and bilateral salpingo-oophorectomy were performed. The left ovarian tumor was 25 × 20 × 12 cm in size and a multicystic tumor containing yellowish mucus without a solid part. Histologically, the cyst wall was covered with mucus cells with focal mild-to-moderate cellular atypia, forming LEGH-like architectures. The glandular cells were immunohistochemically positive for MUC5AC, MUC6 (focal), HIK1083 (focal), and HNF4α. Stromal invasion was not observed. Cervical lesions were not observed. The final pathological diagnosis was OMBT showing atypical LEGH morphology. Targeted sequencing of nontumor tissues revealed the germline STK11 p.F354L variant. Six months later, peritoneal dissemination of adenocarcinoma showing features similar to those of the ovarian tumor was observed, and the patient died of the disease. In summary, we report a case of OMBT with an atypical LEGH-like appearance in a patient with germline STK11 p.F354L variant. This case provides us with unresolved questions regarding the pathogenicity of this STK11 variant and the malignant potential of OMBT with this unusual morphology.

Background. Ganglioneuroblastoma is a borderline tumor of sympathetic origin that is considered a childhood disease, with the majority of patients occurring in children less than five years old and few patients occurring in adults. There are no treatment guidelines for adult ganglioneuroblastoma. Here, we report a rare patient of adult gastric ganglioneuroblastoma that was completely resected by a laparoscopic approach. Case presentation. A 73-year-old man presented with dull pain in the upper abdomen along with abdominal distension for one month. Gastroscopy examination revealed chronic gastritis and submucosal tumors of the gastric antrum. Endoscopic ultrasonography showed a hypoechoic mass in the gastric antrum arising from the muscularis propria. An abdominal computed tomography scan revealed an irregular soft tissue mass in the gastric antrum with heterogeneous enhancement in the arterial phase. The mass was completely resected by laparoscopic surgery. Postoperative histopathology revealed that the mass contained differentiated neuroblasts, mature ganglion cells and ganglioneuroma components. The pathological diagnosis was ganglioneuroblastoma intermixed, and the patient was determined to be in stage I. The patient received no adjuvant chemotherapy or radiotherapy. At his two-year follow-up, the patient was doing well and showed no signs of recurrence. Conclusion. Despite the rarity of gastric ganglioneuroblastoma as a primary site of origin, it should be considered in the differential diagnosis of gastric masses in adults. Radical surgery is sufficient for the treatment of ganglioneuroblastoma intermixed, and long-term follow-up should be performed.

Sinonasal glomangiopericytoma is an uncommon mesenchymal tumor with a perivascular myoid phenotype, which is categorized as a borderline/low-grade malignant soft tissue tumor by the current World Health Organization Classification of Head and Neck tumors. Here, we present the case of a 53-year-old woman with an unusual spindle cell morphology of sinonasal glomangiopericytoma arising in the nasal cavity, mimicking solitary fibrous tumor. Microscopically, the tumor showed a cellular proliferation of spindle cells in fascicles including a focal long sweeping arrangement or whorls, or with a storiform growth pattern, associated with hemangiopericytoma-like gaping blood vessels embedded in a fibrous stroma. This arrangement of the spindle cells faintly indicated a solitary fibrous tumor rather than sinonasal glomangiopericytoma. Immunohistochemically, the tumor was positively reactive to not only beta-catenin (in the nuclei) but also CD34, although signal transducers and activators of transcription 6 was negative. Mutational analysis using Sanger sequencing detected a CTNNB1 mutation. We finally diagnosed the tumor as a sinonasal glomangiopericytoma, showing an unusual spindle cell variant. Such unusual spindle cell morphology with CD34-immunoreactivity potentially leads to an incorrect diagnosis of solitary fibrous tumor because such prominent fascicles including long sweeping structures, reminiscent of desmoid-type fibromatosis, have scarcely been described in the literature. Hence, careful morphological scrutiny using appropriate diagnostic adjuncts is necessary for correct diagnosis.

Percutaneous image-guided biopsies are becoming increasingly common in routine pathology practice, with the greater omentum emerging as a common target. We present herein an account of a middle-aged lady with a complex ovarian mass, omental thickening, and raised serum CA125; clinically suspected to have advanced ovarian malignancy. Fine needle aspiration cytology (FNAC) from the ovarian mass was inconclusive. Omental biopsy revealed only refractile, birefringent crystalline material with surrounding foreign body giant cell reaction; thus surprising the clinical team. Subsequent resection of the ovarian mass showed a teratoma composed exclusively of thyroid tissue, diagnosed as struma ovarii. The omental crystals, interpreted as calcium oxalate crystals, were possibly a consequence of colloid seeding during the ovarian mass FNAC.

Papillary hemangioma is a novel variant of intravascular hemangioma. It is more common in adults and has a male predominance. Most tumors reported so far are solitary and cutaneous. Here we present a rare case of an intraosseous papillary hemangioma involving the frontal bone. Brain imaging in a 69-year-old man with a slowly enlarging swelling on the right frontal area following an accidental fall demonstrated a 4.5 cm × 1.7 cm × 4.2 cm mass originating from the right frontal bone, with a tiny defect on the orbital roof. A malignant process was favored, and the mass was removed. Histopathology revealed a vascular lesion showing intraosseous distribution with foci of extension into the fibrous connective tissue. There were areas of plump endothelial cells with intracytoplasmic hyaline globules arranged in papillary configuration. The lesional cells were immunoreactive with CD34. AE1/AE3, EMA, PR, D2-40, inhibin, and S100 stains were negative. Ki-67 was low. This is the first intraosseous and second noncutaneous papillary hemangioma. Clinically it differs from other cases by the presence of trauma as a preceding event. Since its prognosis is unknown such patients should be monitored for recurrence or malignant transformation.

Background. Enteric duplication cysts are rare but can occur in various parts of the gastrointestinal tract, including the pancreas. Most enteric duplication cysts are benign; however, neoplastic transformation has been reported in a few cases, with adenocarcinoma being the most common malignant transformation. Case Presentation. We present an adult with a pancreatic enteric duplication cyst and low-grade mucinous neoplasm. The patient did not exhibit any clinically significant symptoms or physical signs. Imaging revealed a cystic mass in the pancreatic head. Upon pathological examination, the cyst was found to have a bilayered muscular wall with an inner surface lined with pseudostratified mucinous columnar epitheliums. High-power microscopy revealed low-grade dysplasia in epithelial cells. The final pathological diagnosis confirmed an enteric duplication cyst with a low-grade mucinous neoplasm. Conclusion. To the best of our knowledge, this is the first reported case of a low-grade mucinous neoplasm occurring in an enteric duplication cyst in the pancreas. The importance of complete surgical resection and adequate pathological sampling is emphasized to avoid the missed detection of dysplasia or malignancy in these duplication cysts.