Orbital extranodal marginal zone lymphoma arising during pregnancy: a case report.

A 37-year-old, previously healthy woman presented during her first trimester of pregnancy with a two-week history of rapidly progressive proptosis in the left eye. Clinical examination revealed limited left supraduction and diplopia in upward gaze. Orbital magnetic resonance imaging showed a medial orbital mass adjacent to the globe with secondary proptosis. Pathologic examination of a biopsied specimen of the orbital mass and subsequent immunophenotyping by flow cytometry revealed an extranodal marginal zone B-cell lymphoma. Clinical and histological features as well as a review of the literature are described.

Low-Volume Lymph Node Metastases in Endometrial Carcinoma.

OBJECTIVE: The aim of this study was to determine the histopathologic characteristics of patients with endometrial carcinoma with low-volume metastases (micrometastases and isolated tumor cells) compared with macrometastases. METHODS: We performed a retrospective review of patients with endometrial carcinoma. RESULTS: Among 350 robotic-assisted hysterectomies for endometrial cancer, 187 (53%) underwent attempted sentinel lymph node (SLN) biopsy. At least 1 SLN was detected in 185, a 99% overall detection rate; 108 (58%) also had non-SLNs removed. Among 91 patients with SLNs and non-SLNs from the ipsilateral hemipelvis, both were negative in 74 (81%) and positive in 7 (8%), and 10 (11%) had a positive SLN with negative non-SLNs. Among 17 patients with SLNs and non-SLNs from the contralateral hemipelvis, both were negative in 12 (71%), both were positive in 3 (18%), and 2 patients (12%) had negative SLNs with contralateral positive non-SLNs. Among 79 patients with only a SLN dissection, 4 (5%) were positive; among 69 patients with only a non-SLN dissection, 14 (20%) had positive lymph nodes. Among 24 patients with metastatic SLNs, 9 (38%) had isolated tumor cells, 3 (13%) had micrometastases, and 12 (50%) had macrometastases. Among the 40 total patients with metastatic lymph nodes, low-volume metastases represented the largest metastatic deposit in one third of patients, all of which had SLN dissection. All 12 with low-volume metastases had endometrioid histology compared with less than half (46%) of those with macrometastases (P < 0.01). Grade 1 carcinoma was present in 7 (58%) of the patients with low-volume metastases compared with 4 (14%) of those with macrometastases (P < 0.01) Furthermore, significantly more patients with low-volume metastases versus macrometastases had less than 50% myometrial invasion (67% vs 4%, P < 0.001). CONCLUSIONS: Low-volume disease was present in one third of patients with nodal metastases, the largest metastatic deposit only in patients who had SLN dissection; these patients were significantly more likely to have grade 1 endometrioid carcinoma with less than 50% myometrial invasion, traditional "low-risk" features.

Atypical presentation of bilateral Epstein-Barr virus dacryoadenitis: a case report of corticosteroid resistant orbital inflammation.

Epstein-Barr virus is a known cause of dacryoadenitis that is typically sensitive to corticosteroid treatment. When affecting the orbit, particularly the lacrimal gland, Epstein-Barr virus may cause chronic proptosis and a bilateral lacrimal mass effect. We provide a case of bilateral Epstein-Barr virus associated dacryoadenitis initially resistant to corticosteroid treatment requiring biopsy and confirmation by polymerase chain reaction of lacrimal tissue. Herein, we discuss the presentation with associated magnetic resonance imaging and histopathologic images, diagnostic dilemma, and treatment of an atypical case.

Low grade intracranial meningioma presenting with pulmonary metastasis: Case report and literature review.

Meningioma is a common neoplasm in the central nervous system. Even though most meningiomas tend to have a benign, indolent clinical course, metastasis can occur. We describe a case of a 59-year-old woman who presented with an incidental finding of multiple lung masses. The patient underwent a wedge lung excision, and a diagnosis of meningioma was rendered. Magnetic resonance imaging of the brain revealed an extra-axial mass with left transverse venous sinus involvement, supporting the diagnosis of metastatic meningioma to the lung. Metastatic meningioma can be a challenging diagnosis in a patient with no previous diagnosis of an intracranial lesion. Thus, it should be considered in the differential diagnosis when encountering a spindled cell proliferation with a whorled pattern and psammoma bodies. Positive immunohistochemical staining with epithelial membrane antigen (EMA) and vimentin may be helpful in achieving the diagnosis.

Intraoperative Squash and Touch Preparation Cytology of Brain Lesions Stained with H+E and Diff-Quik™: A 20-Year Retrospective Analysis and Comparative Literature Review.

OBJECTIVE: Squash preparation (SP) is a rapid technique for the intraoperative assessment of brain lesions. Only a few studies have employed touch preparation (TP) cytology and Diff-QuikTM (DQ) staining in conjunction with SP. Our study aimed to assess the diagnostic efficacy of SP of brain lesions at our institution, ascertain the additional effect of TP and DQ staining, examine factors affecting the sensitivity and specificity of our methods, and compare our findings with those of previous investigations. STUDY DESIGN: Our database was searched for all SP/TP of brain lesions examined from January 1996 to December 2016. RESULTS: During this 20-year study period, our search revealed 400 brain lesions diagnosed by SP/TP cytology. There were 338 (84.5%) neoplasms and 62 (15.5%) nonneoplastic lesions. The most common neoplasms were glioblastoma multiforme (24.6%), metastatic cancer (18.3%), meningioma (16.9%), astrocytoma (11.5%), lymphoma (8.3%), oligoastrocytoma (3.3%), and pituitary adenoma (3.3%). There was discordance between the SP/TP and histological diagnoses in 19/338 (5.6%) cases, i.e., 12 misclassifications of tumor subtype and 7 sampling errors. No false-positive cases were detected. CONCLUSION: Brain SP/TP stained with H+E/DQ demonstrated high sensitivity (97.9%), specificity (100%), and overall diagnostic accuracy (95.3%). The combined methods, in particular, aided in the diagnosis of brain tumors prone to smearing artifacts and certain metastatic malignancies.

The Clinical Significance of Endometrial Cells Detected on Pap Testing: The Impact of Revisions to the 3rd Edition of the Bethesda System for Reporting Cervical Cytology.

GOALS: This study aims to examine the effects of raising the reporting age for benign endometrial cells (BEC) on Papanicolaou (Pap) tests according to the 2014 3rd edition of the Bethesda System for Cervical Cytology, as well as the sequelae of the 2012 American Society of Colposcopy and Cervical Pathology (ASCCP) guidelines recommending endometrial asessment only for postmenopausal or symptomatic premenopausal women. PROCEDURES: We retrospectively examined clinical and histologic data from 4438 women aged ≥40 with BEC on Pap tests, of whom 608 (14%) were biopsied. RESULTS: Fifty-three (8.7%) histologic abnormalities were discovered upon biopsy. There was no significant difference (p=0.52) in abnormalities found between premenopausal women aged ≥40 and premenopausal women aged ≥45. Furthermore, there were no high-grade cancers in women between ages 40-44. There were also 3 high-grade cancers in patients aged 46, 46, and 49. Each of these women was asymptomatic and premenopausal. CONCLUSION: Our results affirm the raising of the reporting age of BEC on Pap tests from 40 to 45 in our patient population. Because there were 3 asymptomatic, premenopausal patients with high-grade cancers in our 45-49 age group, we cannot completely adhere to the ASCCP guidelines nor can we advocate raising the reporting age further to 50. Other laboratories must review their own follow-up data to validate appropriate reporting criteria for BEC for their patients.

Ovarian needle aspiration in the diagnosis and management of ovarian masses.

OBJECTIVE: Ovarian needle aspiration and biopsy (ONAB) may be employed for pretreatment diagnosis of ovarian malignancies or intraoperatively to facilitate removal of ovarian masses. However, there is reluctance to utilize this procedure due to potential cyst rupture or seeding of malignant cells. The objective of this study was to examine the efficacy of ONAB over a 13-year period at our institution. METHODS: Between 2000 and 2013, all ONAB specimens were identified from the Queen's Medical Center Pathology Department database. All cytologic specimens were reviewed and correlated with histopathologic findings. A retrospective chart review was conducted to retrieve data on clinical course and treatment. RESULTS: This study identified 144 cases of ovarian masses sampled by aspiration or needle biopsy between 2000 and 2013. Ninety-two (64%) cases had corresponding histopathology, 84 (91%) of which were obtained concomitantly. On histology, 12 (13%) cases were malignant and 80 (87%) benign. Three false negative cases were noted; 2 serous borderline tumors and 1 mucinous cystadenocarcinoma. These were sampling errors; no diagnostic tumor cells were present in the aspirates. Sensitivity and specificity of ONAB in the detection of malignancy were 75% and 100%, respectively. The positive and negative predictive values were 100% and 96%, respectively. CONCLUSION: ONAB represents a valuable tool in the diagnosis of malignancy and treatment of ovarian masses. In our study, it was highly specific, with excellent positive and negative predictive value.

Metastatic neoplasms to the thyroid diagnosed by fine-needle aspiration/core needle biopsy: Clinicopathologic and cytomorphologic correlation.

BACKGROUND: Although thyroid fine-needle aspiration (FNA) and core needle biopsy (CNB) are commonly utilized modalities in the evaluation of thyroid nodules, metastatic tumors to the thyroid are only rarely encountered. We aspired to determine the incidence and primary origin of metastases to the thyroid at our institution and to examine their clinicopathologic and cytomorphologic features. MATERIALS AND METHODS: A search of our database was undertaken to review all thyroid FNA and/or CNB examined between January 2004 and December 2013. RESULTS: During our 10 year study period, 7497 patients underwent 13,182 FNA and/or CNB. Four hundred sixty one (6%) patients were diagnosed with neoplasms. Only five (1.1%) were found to have metastatic tumors to the thyroid involving three females and two males. Two were diagnosed by FNA, one by CNB, and two by both FNA and CNB, with rapid on-site evaluation (ROSE) employed in all cases. The primary malignancies in the five cases were pulmonary and nasopharyngeal squamous cell carcinomas, renal cell carcinoma, pancreatic adenocarcinoma, and olfactory neuroblastoma. The cytomorphologic features of these metastases to the thyroid aided in their distinction from primary thyroid carcinoma. Two of these metastases, a renal cell carcinoma and pancreatic adenocarcinoma, were the first clinical manifestations of cancer. CONCLUSION: Metastases to the thyroid diagnosed by FNA and/or CNB are exceedingly rare in our institution, comprising only 0.04% of total FNA/CNB and only 1.1% of all thyroid neoplasms. We report the first known case of metastatic olfactory neuroblastoma to the thyroid diagnosed by aspiration cytology. In addition, an occult primary may present as a thyroid mass on FNA or CNB as occurred with two of our cases. FNA/CNB proved to be highly effective in the diagnosis of metastases to the thyroid, with ROSE proving valuable in assuring specimen adequacy. Thyroid FNA and CNB demonstrated great utility in the setting of metastatic disease, obviating the need for more invasive procedures.

Placental site trophoblastic tumor with sole metastasis to breast: A case report.

Placental site trophoblastic tumor (PSTT) is a rare form of gestational trophoblastic neoplasia (GTN). It most commonly occurs after a delivery but may arise after any type of pregnancy. PSTT arises after neoplastic transformation of intermediate trophoblastic cells. The most commonly reported symptoms are abnormal bleeding or amenorrhea. Due to the rarity of this disease, evidence on prognostic factors as well as optimal treatment is limited. While treatment for early-stage disease is usually limited to surgery, multimodal treatment with chemotherapy and surgery may be important for metastatic disease. Metastatic disease may be associated with minimal elevations of human chorionic gonadotropin (hCG). Here we present an unusual case of a patient with PSTT and an isolated breast metastasis who was successfully treated with surgical resection and single-agent chemotherapy.

Metastatic genitourinary cancer diagnosed by body fluid cytology: clinicopathologic and cytomorphologic correlation.

INTRODUCTION: Malignant effusions secondary to genitourinary cancers constitute less than 5% of metastatic malignancies. Because of their rarity, definitive cytodiagnosis may be challenging. Our study aims to examine the incidence of malignant fluids secondary to genitourinary cancers in our institution, and to characterize their clinicopathologic and cytomorphologic features. METHODS: A search of our database was undertaken for all body fluids reviewed from January 2003 through April 2014 at our institution. RESULTS: During this 11.3-year study period, our search revealed 8255 body fluids. Of these, 1341 (16.2%) were malignant with only 15 (0.2%) due to a genitourinary primary, constituting a mere 1.1% of all malignant fluids. Eight cases (53%) were urothelial carcinomas, 6 (40%) were renal cell carcinomas, and 1 was a bladder leiomyosarcoma (7%). No prostate cancers were found. Seven (47%) involved the pleura, 6 (40%) were in the peritoneum, and 2 (13%) were in the cerebrospinal fluid (CSF). None were detected in the pericardium. Genitourinary metastases comprised 1.9% of peritoneal, 0.8% of pleural, 1.9% of CSF malignant fluids. CONCLUSION: Metastatic genitourinary cancers in body fluids are rare, comprising only 0.2% of all fluids and 1.1% of all malignancies. The cytomorphologic features of metastatic urothelial and renal cell carcinoma, although similar to those described in the literature, are nonspecific. To our knowledge, this is the first reported case of metastatic bladder leiomyosarcoma in ascites diagnosed by effusion cytology. Because leiomyosarcoma in body fluids can demonstrate epithelioid features and cohesiveness, it may be confused with metastatic carcinomas.

Metastatic neoplasms to the pancreas diagnosed by fine-needle aspiration/biopsy cytology: A 15-year retrospective analysis.

BACKGROUND: Metastatic tumors to the pancreas are rarely encountered and diagnostically challenging. We aspired to determine the incidence and origin of all metastases to the pancreas at our institution, and to examine their clinicopathologic and cytomorphologic features. We also sought to ascertain the effect of endoscopic ultrasound (EUS) guidance implementation. METHODS: A search of our database was undertaken to review all pancreatic FNA and/or CNB examined from January 2000 through December 2014. RESULTS: During our 15-year study, 636 patients underwent pancreatic FNA/CNB, including 252 (40%) computerized tomography (CT) and 384 (60%) EUS-guided biopsies. Malignancy was diagnosed in 221 (35%). Only 16 had metastases to the pancreas, comprising 2.5% of pancreatic biopsies and 7.2% of malignancies. Three (18.8%) presented with their first manifestation of cancer. EUS guidance was utilized in 50%, with rapid on-site evaluation (ROSE) employed in 14 (88%). The most common primary site was lung (6,38%), followed by 3 (19%) each of renal and gastrointestinal malignancies. The remaining included malignant melanoma, Merkel and gallbladder small cell carcinomas, and olfactory neuroblastoma. CONCLUSION: Cytologic diagnosis of metastasis to the pancreas is rare in our institution, comprising only 2.5% and 7.2% of total and malignant pancreatic FNA/CNB, respectively. FNA/CNB with ROSE proved to be an effective diagnostic modality, thereby obviating the need for more invasive procedures in the setting of pancreatic metastases. EUS-FNA was equally effective as CT-guided biopsies in achieving specimen adequacy and definitive diagnoses. We also present the first known case of a metastatic olfactory neuroblastoma to the pancreas diagnosed by imprint cytology.

A Combined Deposition of Lanthanum and ß2-Microglobulin-Related Amyloid in the Gastroduodenal Mucosa of Hemodialysis-Dependent Patients: An Immunohistochemical, Electron Microscopic, and Energy Dispersive X-Ray Spectrometric Analysis.

Lanthanum carbonate (LC) is a new type of phosphate adsorbent used to treat patients with hyperphosphatemia caused by chronic kidney diseases. Recent studies have pointed out that lanthanum deposition can be found in the cytoplasm of histiocytes in the gastroduodenal mucosa of these patients. On the other hand, it is well known that patients on long-term hemodialysis can develop deposition of ß2-microglobulin-related amyloid (Aß2M) mainly around joints. However, involvement of the gastrointestinal tract by hemodialysis-associated amyloidosis has been thought to be rare, and therefore only Aß2M, if any, has been reported to accumulate in the vascular walls of the submucosa and muscularis propria. Thus, in contrast to AA amyloid, biopsy from gastrointestinal mucosa has long been considered to have little significance in detecting amyloid. We present unusual histologic findings on biopsy specimens taken from the gastroduodenal mucosa of 7 hemodialysis-dependent patients taking LC for more than a year. These findings were due to a combined deposition of lanthanum and ß2-microglobulin-related amyloid in the cytoplasm of histiocytes. The deposition of amyloid was confirmed by conventional histochemistry, immunohistochemistry, and transmission electron microscopy, and that of lanthanum by transmission electron microscopy and scanning electron microscopy/energy dispersive X-ray spectrometry. This is the first report of such a peculiar combined deposition of lanthanum and amyloid in the gastroduodenal mucosa of hemodialysis patients. Although the exact mechanism of combination and pathogenesis is unclear, we believe that histologic examination of the gastrointestinal mucosa should be considered in the careful follow-up and observation of hemodialysis patients taking LC.

Efficacy of endoscopic ultrasound-guided fine-needle aspiration and core needle biopsy in the diagnosis of upper gastrointestinal submucosal lesions.

INTRODUCTION: Endoscopic ultrasonographically guided fine-needle aspiration (EUS-FNA) has been increasingly utilized to evaluate submucosal lesions of the upper gastrointestinal (UGI) tract. Our study aims to determine the efficacy of UGI EUS-FNA/core needle biopsy (CNB), including the frequency and cytomorphologic features of encountered submucosal lesions, and to investigate contributing factors including the role of rapid on-site evaluation (ROSE). METHODS: We analyzed all UGI submucosal lesions diagnosed at our institution by EUS-FNA/CNB from September 2008 through August 2015. RESULTS: During this 8-year study period, 94 patients underwent 110 UGI EUS-FNA/CNB, including 89 (81%) gastric, 11 (10%) duodenal, and 10 (9%) esophageal lesions. Twenty-seven (25%) were gastrointestinal stromal tumors (GISTs), followed by 13 (12%) leiomyomas, 5 (5%) schwannomas, 4 (4%) gastric adenocarcinomas, 3 (3%) neuroendocrine tumors (NETs), and 3 (3%) pancreatic heterotopias. All GISTs, leiomyomas, and NETs were ultimately diagnosed by EUS biopsies, as well as 75% of adenocarcinomas, 60% of schwannomas, and 33% of pancreatic heterotopias. The specificity of EUS-FNA/CNB for these 6 most commonly encountered lesions was 100%, with sensitivity of 82%. Sensitivity was 100% for esophageal and duodenal biopsies, and 80% and 75% for gastric and gastroesophageal procedures, respectively. Factors that contributed to poor yield included the lack of ROSE, small lesional size, lesion location and histology, and needle type. Neither number of needle passes nor operator experience appeared to influence specimen adequacy. CONCLUSION: EUS-FNA/CNB is an effective modality for diagnosing UGI submucosal lesions. Awareness of potential errors due to sampling of the bowel wall, lesional cystic degeneration, as well as pancreatic heterotopia and Brunner gland hamartoma is essential in order to avoid false diagnoses.

A Rare Case of Lateral Canthal Gouty Tophus Presenting as an Eyelid Mass.

A 41-year-old man with a history of gout presented with an enlarging eyelid growth. Clinical examination revealed a mildly indurated nodule at the lateral canthus. Following resection, histopathological examination revealed needle-shaped, crystalline material surrounded by multinucleated giant cells, findings consistent with gouty tophus. This represents just the sixth case of gouty tophus of the eyelid reported in the literature.

Volume of lymphatic metastases does not independently influence prognosis in colorectal cancer.

PURPOSE: To evaluate the prognostic relevance of the volume of nodal metastatic disease in colorectal cancer patients. PATIENTS AND METHODS: One hundred node-positive patients with T2 or T3 carcinoma of the colon or rectum after routine histologic examination of the regional nodes were studied. The metastatic tumor was measured with an ocular micrometer, and the tumor volume was determined. RESULTS: The mean lymph node metastatic tumor volume was 5.1 +/- 4.99 mm(3) (range, 0.05 to 83,434 mm(3)). There was only a weak positive correlation with number of nodes involved with metastatic disease and tumor volume in nodes (r =.45). Median follow-up was 39 months (range, 1 to 87 months). The number of nodes was highly predictive of outcome. Individuals with one to three positive nodes had a substantially better survival than individuals with four or more positive nodes (P <.001). The volume of nodal metastatic disease correlated with outcome (P =.019). Patients dying as a result of disease had substantially greater mean metastatic nodal volume than those who were alive (3,705 v 1,783 mm(3); P =.036). However, the total metastatic nodal volume did not, independent of positive nodes or number of positive nodes, predict outcome. Individuals with micrometastatic nodal volume did not have improved survival when compared with individuals with macrometastatic nodal volume (P =.79). CONCLUSION: The number of nodes involved with metastatic tumor, rather the volume of metastatic involvement of the regional lymph nodes, predicts outcome. These results suggest that micrometastatic disease may have a similar prognosis as macrometastatic disease when the same number of lymph nodes are involved with metastatic tumor.

Recurrent papillary thyroid carcinoma with pleural metastasis diagnosed by effusion cytology: a report of cases with clinicopathologic correlation.

Papillary thyroid carcinoma (PTC) is typically an indolent disease characterized by slow growth and a favorable prognosis. In rare instances, this disease may metastasize to the pleura and manifest as a malignant pleural effusion. We report 3 female patients of Japanese/Okinawan ancestry with a history of PTC who presented with hydrothorax. Cytologic examination in conjunction with immunohistochemical staining enabled a definitive diagnosis of metastatic PTC. Molecular analysis of the mitogen activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K) pathways demonstrated the presence of the v-raf murine sarcoma viral oncogene homolog B (BRAF)(V600E) mutation in 2 of our 3 patients, with the absence of any other clinically significant mutations in all cases. Further investigation is necessary to elucidate the molecular and environmental mechanisms involved in this aggressive manifestation of PTC.

Pleomorphic adenoma of breast: a radiological and pathological study of a common tumor in an uncommon location.

Pleomorphic adenoma occurs commonly in the major salivary glands but is uncommonly encountered in the breast. In both of these locations, the tumor is typically grossly circumscribed and has a "mixed" histological appearance, being composed of myoepithelial and epithelial components amid a myxochondroid matrix. Herein, we report a case of pleomorphic adenoma of the breast which was preoperatively thought to represent a fibroadenoma on clinical and radiological grounds. It is the rarity of the tumor in the breast, rather than its histological appearance, that causes diagnostic difficulty.

The LAST guidelines in clinical practice: implementing recommendations for p16 use.

OBJECTIVES: To determine the impact of implementing p16 Lower Anogenital Squamous Terminology Standardization Project for HPV-Associated Lesions (LAST) guidelines, we compared p16 use and follow-up data before and after implementation of the guidelines. METHODS: We reviewed all cervical biopsy specimens diagnosed by two pathologists before and after implementation of the LAST guidelines and calculated the rate of and reason for p16 use across all biopsy specimens, high-grade squamous intraepithelial lesion (HSIL) detection, and follow-up. RESULTS: In total, 1,829 and 1,623 cervical biopsy specimens were reviewed in periods A and B, respectively. Overall p16 use increased from 2.8% to 6.2% (P < .001). Recommendations 2 and 4 increased from 0.16% and 0% of all cervical biopsy specimens in period A to 1.4% and 1.9% in period B, respectively (P < .0001). p16+ HSIL increased from 1.4% to 2.3% (P < .05). The positive predictive value of p16+ HSIL increased from 48% to 76% (P < .05). CONCLUSIONS: Implementation of the p16 LAST guidelines resulted in a significant increase in p16 use and a significant increase in the positive predictive value of p16+ HSIL.

Tibial bone metastasis as an initial presentation of endometrial carcinoma diagnosed by fine-needle aspiration cytology: A case report and review of the literature.

Endometrial cancer is the most common gynecologic malignancy in the United States. However, bony metastasis is infrequent and exceptionally rare as the initial presentation. We report a case of a 77-year-old female with a clinically silent endometrial carcinoma who presented with a left tibial metastasis as the first manifestation of her disease. Ours is only the third case diagnosed by fine-needle aspiration (FNA) cytology, and the first to detail the cytomorphologic features of metastatic endometrial cancer to bone. These microscopic findings, including three-dimensional cohesive clusters with cellular overlapping and cuboidal to columnar cells exhibiting low nuclear: cytoplasmic ratios and partially vacuolated cytoplasm, differ significantly from those of endometrial carcinoma on a Papanicolaou test. The tumor bore similarity to the more commonly encountered metastatic colon cancer, but immunohistochemical staining enabled reliable distinction between these entities. A review of osseous metastases of endometrial cancer demonstrates a predilection for bones of the lower extremity and pelvis with a predominance of the endometrioid histologic subtype. In about a quarter of the cases, the bony metastasis was the first manifestation of the cancer. FNA was an effective diagnostic modality for this unusual presentation of a common malignancy. Awareness of this entity and its differential diagnosis is essential for accurate and timely diagnosis.

The number and distribution of eosinophils in the adult human gastrointestinal tract: a study and comparison of racial and environmental factors.

There are surprisingly limited data regarding normal counts or distribution of eosinophils in the gastrointestinal tract, despite the increasing incidence of eosinophilic gastrointestinal tract diseases. Moreover, there are no published reports on the eosinophil number throughout the gastrointestinal tract of adults or Asian populations, or those investigating the effect of race on eosinophil count. First, in our study, the number of eosinophils from each portion of the gastrointestinal mucosa was quantified on biopsy slides from a Japanese adult population (132 samples). Next, the surgical resections from Japanese (110 samples), Japanese Americans (64), and Caucasians (57) were used to investigate the racial and environmental effects. Our results with the Japanese biopsy samples showed a significant increase in the number of eosinophils from the esophagus to the right colon (mean±SD/mm: 0.07±0.43 for the esophagus, 12.18±11.39 for the stomach, and 36.59±15.50 for the right colon), compared with a decrease in the left colon (8.53±7.83). Investigation using surgical samples showed that the distribution patterns in the gastrointestinal tract were very similar among the 3 ethnic groups, and there were no significant differences in the number of eosinophils among these groups, except in the esophageal epithelium. This study is the first report on the normal numbers and distribution of eosinophils throughout the gastrointestinal tract not only of an Asian population but also of adults. Our data suggest that a cutoff value for eosinophil counts, when rendering a diagnosis of eosinophilic gastrointestinal tract disease, should be individualized to the different biopsy sites. Interestingly, race and environmental factors did not seem to have a significant effect on eosinophil densities and distributions.