Mass-forming Lesion Research Articles

Extra-Axial Poorly Differentiated Chordoma Initially Misdiagnosed as Epithelioid Sarcoma.

Poorly differentiated chordoma is an exceedingly rare, aggressive subtype of chordoma. These tumors typically arise in the axial skeleton of young patients, most commonly the skull base, followed by the cervical spine. Herein, we present a 60-year-old patient with longstanding knee pain and nondiagnostic imaging, initially thought to be due to osteoarthritis. No discrete mass-forming lesion was identified by radiology. Synovial histology at the time of arthroplasty revealed a multinodular proliferation of epithelioid-to-histiocytoid cells with a moderate amount of eosinophilic-to-clear, vacuolated cytoplasm. Scattered cells with high-grade nuclear atypia were present. A diagnosis of metastatic carcinoma was considered due to immunohistochemical positivity for keratin and GATA3. However, a diagnosis of epithelioid sarcoma was rendered based on clinical context, morphology, and loss of immunohistochemical expression for SMARCB1 (INI1). However, upon re-review of the tumor, brachyury was retrospectively added to the immunohistochemistry panel and showed strong positivity, thus prompting amendment of the initial diagnosis of epithelioid sarcoma to extra-axial poorly differentiated chordoma. Given the rarity of this diagnosis, molecular testing was performed which revealed a unique SMARCB1 molecular profile with a single-nucleotide variant in addition to the commonly reported loss of chromosome 22q. This report of an ultra-rare sarcoma in an uncommon anatomic site highlights multiple potential pitfalls in the diagnosis of poorly differentiated chordoma, emphasizes the importance of brachyury immunohistochemistry in rendering a correct interpretation, and underscores an opportunity for further molecular analysis to better define the molecular profile of this entity.

Perinephric Myxoid Pseudotumor of Fat: A Series of 13 Cases and Literature Review

Perinephric myxoid pseudotumor of fat (PMPF) is a recently described and rare retroperitoneal mass-forming lesion whose clinical significance chiefly involves mimicry of a variety of soft tissue tumors. For unknown reasons, it commonly occurs in male patients with underlying non-neoplastic renal diseases and/or type 2 diabetes (DMT2). A total of 55 cases have been reported in the literature. Recently, we have encountered 13 such masses with peculiar histologic features; thus, we sought to investigate our experience and review the clinicopathologic characteristics of the literature. Our series confirms that PMPF frequently occurs in adult male patients (11/13, 85%), with an average age of 66 years, and commonly co-occurs with renal disease, such as DMT2 (2/13, 15%), end-stage renal disease (ESRD) (5/13, 39%), renal cysts (4/13, 31%), concurrent or prior renal neoplasia (2/13; 15%), and myeloma/lymphoma (2/13; 15%). Histologic evaluation shows lipomatous masses commonly showing variable amounts of fat necrosis, myxoid degeneration, lymphoplasmacytic inflammation and lacking atypical hyperchromatic stromal spindle cells. Unusual histologic features include extramedullary hematopoiesis (1/13, 8%), hemosiderin deposition (4/13, 31%), and small wisps of mature smooth muscle (6/13, 46%). All cases tested were negative for MDM2 and did not show an increased ratio of IgG4+/IgG+ plasma cells. Our study confirms the clinical and pathologic features of PMPF and expands its histologic spectrum, underscoring the importance of this entity as a benign pseudotumor which should be included in the differential diagnosis of other fat-containing retroperitoneal masses, particularly well-differentiated liposarcoma.

Colorectal metastases with intrabiliary growth: incidence, treatment, and outcomes.

Intrabiliary growth (IG) is an unusual modality for colorectal metastases to spread. Relatively little is known about this condition because large series are lacking. The aim of the study was to compare the surgical and oncological outcomes of patients with or without IG. From 01/2010 to 12/2020, 999 patients underwent hepatectomy for colorectal metastases. Clinicopathological variables were retrospectively analyzed from a prospective-collected database of patients with or without IG. A propensity score matched (PSM) analysis to compare OS and DFS was performed. At first hepatectomy, 29 patients (2.9%) had IG: 7 isolated IG and 22 mixed-type (mass-forming lesion with IG). 4 patients presented IG at repeat hepatectomy for recurrence, of whom 3 had no biliary invasion at initial surgery. IG resulted to be more common in older patients (median age 70 in IG vs 60years of no-IG, p = 0.004). Mean time from colorectal tumor was longer in IG (20.4months) than no-IG (12.9months), p = 0.038. Major hepatectomies (55.2% IG vs 29.7% no-IG, p = 0.003) and anatomic resections (89.7% vs 58.2%, p = 0.001) were more frequently required to treat IG. In 5 (17%) of IG, a resection of main bile duct was performed. Overall postoperative mortality and complications were similar in the two groups, while bile leak was 17.2% IG vs 5.6% no-IG (p = 0.024). Median margin width was comparable in IG (1.4mm) and no-IG (2mm). Five-year overall survival (IG 45.9% vs no-IG 44.5%) and Disease-Free Survival (IG 35.9% vs no-IG 36.6%) were similar in the two groups. According to PSM, 145 patients with no-IG were compared to 29 of IG group. After PSM, OS and DFS did not show any statistically significant difference. IG has similar oncological outcomes of resected colorectal metastases without IG, although it affects surgical management.

Rosai-Dorfman disease of the breast: a clinicoradiologic and pathologic study

Rosai-Dorfman disease (RDD) is an uncommon histiocytic disorder typically involving lymph nodes and less frequently extranodal tissues. RDD involving the breast is rare and may clinically and radiologically mimic neoplastic and non-neoplastic disorders. We report seven patients with breast RDD, describe their clinicoradiologic and pathologic features, and discuss the differential diagnosis. Patients, ranging from 15 to 74 years of age, presented with unilateral and unifocal (5/7) or bilateral and multifocal (2/7) masses. RDD was either confined to the breast (6/7) or concurrently involved a lymph node (1/7). Masses ranged from 8 to 31mm, categorized as Breast Imaging-Reporting and Data System (BI-RADS) 4 (6/7) or 5 (1/7). All cases showed similar morphology with many large histiocytes displaying emperipolesis with associated fibrosis and dense lymphoplasmacytic infiltrate. The abnormal histiocytes co-expressed CD68/CD163, S100, OCT2, and Cyclin D1 (7/7), and were negative for CK AE1/AE3 (7/7), CD1a (7/7), and BRAF V600E (6/6). Flow cytometry (n=3), kappa/lambda in situ hybridization (n=5), and IgG4/IgG immunohistochemistry (n=1) did not reveal lymphoma or IgG4-related disease. No mycobacterial or fungal organisms were identified on acid-fast bacillus (AFB) and Grocott methenamine silver (GMS) stains (n=5). Three patients underwent complete excision and none recurred or progressed to systemic disease during follow-up (88-151 months). In summary, breast RDD should be included in the differential diagnosis of a mass-forming breast lesion. Histopathology with ancillary studies and clinicoradiologic correlation is essential for accurate diagnosis and optimal clinical management. Patients with RDD of the breast have an excellent prognosis after complete excision.

Mass-forming ductal carcinoma in situ: An ultrasonographic and histopathologic correlation study

Ultrasound (US) guided core needle biopsy (CNB) for mass lesions resulting in a diagnosis of ductal carcinoma in situ (DCIS) is often considered radiologically discordant and generates surgical planning difficulty. One hundred cases of US-guided CNB for mass lesions diagnosed as DCIS were collected from 2013 to 2021. Histological features were reviewed and correlated with radiology and surgical excision findings. Thirty (30%) were high-grade (HG), and seventy (70%) were low- to intermediate-grade. Seventy-one (71%) cases had a histological correlate of a mass-forming lesion, including 26 (26%) were associated with benign mass-forming lesions (category 1) such as papilloma, complex sclerosing lesion/radial scar, fibroadenoma, sclerosing adenosis, and ruptured cyst; 23 (23%) were HG with solid pattern, comedo necrosis, and stromal desmoplasia (category 2); and 22 (22%) had predominantly papillary architecture (category 3). Twenty-nine (29%) were discordant with no histologic correlate of a mass lesion (category 4). Follow-up excisions were available in 79 cases. Invasive carcinoma was identified in 14 cases (18%), of which 8 were from the radiologically discordant category (35%), 3 (17%) associated with HG DCIS with desmoplasia, 2 (10%) associated with benign mass lesion and 1(5%) was predominantly papillary architecture. US-guided CNB for mass-forming lesions with a DCIS diagnosis on CNB can be grouped into four categories. Radiology-pathology correlation is essential. This categorization emphasized rad-path correlation and had a clear difference in upgrade rate on follow-up excision. Rad-path discordant biopsy cases were more likely to be associated with a missed invasive carcinoma (p < 0.05).

CT findings and diagnostic performance of upper urinary tract carcinoma in situ.

To evaluate the CT characteristics and detectability of carcinoma in situ (CIS) of the upper urinary tract. Between January 2007 and March 2020, 28 patients (mean age: 73years, 25 male and 3 female) with 29 pure CIS lesions of the upper urinary tract (i.e., without concomitant non-CIS lesion) who underwent nephroureterectomy were identified. The most recent CT scan performed before ureteroscopy, systemic neoadjuvant chemotherapy, or nephroureterectomy was selected for analysis. Twenty-eight patients without upper tract malignancy were selected as a control group. All images were evaluated for presence of upper urinary tract CIS using confidence levels ranging from 1 to 100 by two radiologists. The confidence level of 75 was used as a cutoff threshold for calculating sensitivity and specificity. The median interval between CT scan and nephroureterectomy was 96days. The number of true-positive lesions (per-lesion sensitivity) was 41% (12/29) and 52% (15/29) by readers 1 and 2. The true-positive lesion appeared as wall thickening in 83% (10/12) by reader 1 and 80% (12/15) by reader 2, and as a mass in 17% (2/12) by reader 1 and 20% (3/15) by reader 2. All mass-forming lesions were located in the renal collecting system. The per-patient sensitivity and specificity were 42% and 100% in reader 1, and 54% and 96% in reader 2. The common abnormal finding of pure CIS in the upper urinary tract was wall thickening. Pure CIS could also appear as a mass-forming lesion when it is located in the renal collecting system. • The common abnormal finding of pure CIS in the upper urinary tract is wall thickening. Gradually progressive urothelial wall thickening and/or worsening symptoms should raise the suspicion of CIS. • Pure CIS in the upper urinary tract also appears as a mass-forming lesion when it is located in the renal collecting system. • Hydronephrosis and fat stranding play an auxiliary role in detecting pure CIS in the upper urinary tract.

Hepatic Secondary Syphilis Can Cause a Variety of Histologic Patterns and May Be Negative for Treponeme Immunohistochemistry.

The rate of syphilis in the United States has been increasing steadily in the past decade, but it remains an uncommon diagnosis in tissue biopsies. Most of the pathology literature on hepatic syphilis consists of older series or case reports. This study aimed to systematically characterize the histologic spectrum of hepatic syphilis in a contemporary cohort. Clinicopathologic features of 14 hepatic syphilis cases between 2012 and 2018 were analyzed to characterize the broad spectrum of histologic changes. Thirteen patients were men (age range: 19 to 59 y); 6 had known human immunodeficiency virus, 7 were men known to have sex with men, and no patient had known prior syphilis. Hepatic syphilis was the primary clinical suspicion in only 1 patient. Common symptoms included jaundice, rash, and abdominal pain. Thirteen had elevated transaminases, and 12 had elevated alkaline phosphatase. Pathologic changes were grouped into 5 histologic patterns: biliary-pattern injury (n=5), acute hepatitis (n=4), autoimmune hepatitis-like (n=1), fibroinflammatory mass-forming lesion (n=2), and no particular pattern (n=2). Nearly all showed portal and lobular lymphocytes and plasma cells; 12 had prominent histiocytes/Kupffer cells, 9 had ductular reaction, and 7 had duct inflammation. Occasional focal findings included dropout (n=7), phlebitis (n=7), and loose granulomata (n=5). Treponeme immunohistochemistry was positive in 10 and negative in 4, though treatment was given before biopsy in 3 of those 4. Thirteen patients had rapid plasma reagin testing either before or after biopsy, with 1:64 or higher titer. All patients who received treatment recovered. Hepatic syphilis is rare but likely underrecognized. It exhibits a variety of histologic appearances and therefore should be considered in several hepatic differential diagnoses, especially in men who have sex with men. Kupffer cells, granulomata, and phlebitis may suggest the diagnosis regardless of predominant histologic pattern. Negative treponeme immunohistochemical staining does not exclude the diagnosis, including in untreated patients.

Suture granuloma with hydronephrosis caused by ileostomy closure after rectal cancer surgery: a case report

BackgroundSuture granuloma with hydronephrosis after abdominal surgery is extremely rare. We herein report a successfully treated case of suture granuloma with hydronephrosis caused by ileostomy closure after rectal cancer surgery.Case presentationA 63-year-old male underwent laparoscopic low anterior resection with covering ileostomy. Two months after primary operation, ileostomy closure was performed with two layered hand-sewn suture (Albert–Lembert method) using absorbable suture. In that operation, marginal blood vessels in the mesentery were ligated with silk suture. The patient had remained in remission with no evidence of tumor recurrence, however, 2 years and 5 months after primary surgery, a contrast-enhanced computed tomography (CT) scan showed a mass-forming lesion on the right external iliac artery (43 × 26 mm) and hydronephrosis. Positron emission tomography/computed tomography (PET/CT) showed a mass-forming lesion without high accumulation, which obstructed the right ureter. Recurrence could not be ruled out due to the rapid appearance of tumor and hydronephrosis in the short-term period. Thus, the patient underwent laparotomy. The tumor located in the mesentery near the anastomosis of ileostomy closure and it was strongly adherent to the retroperitoneum, which obstructed the right ureter. The adhesion between the tumor and ureter was carefully dissected and tumor resection with partial small bowel resection was then performed with preservation of the ureter using ureteral stents. Pathological examination of the tumor revealed fibrous proliferation of foreign body granuloma. In the resected tumor, sutures with foreign giant cells were found. Therefore, we diagnosed the tumor as silk suture granuloma, which was caused by the silk suture used to ligate blood vessels of the mesentery at the ileostomy closure. The patient remained well with no evidence of tumor recurrence as 5 years after the primary operation of rectal cancer.ConclusionsSuture granuloma is a rare surgery-related complication in the postoperative surveillance of patients with colorectal cancer. If suture granuloma mimicking local recurrence is a differential diagnosis, it would be important to consider to avoid unnecessary extended resection.

Sclerosing angiomatoid nodular transformation in a child

Abstract Sclerosing angiomatoid nodular transformation (SANT) is a spleen-specific benign mass-forming vascular lesion. Although there have been several reports of cases in the adult population, data in the pediatric population are exceedingly rare. Herein, we present a case of SANT with hypersplenism and investigate the unique features of this disease in pediatric patients. A 14-year-old girl visited a nearby physician with fatigue that had lasted for several months and was diagnosed with severe anemia and thrombocytopenia. Computed tomography revealed marked splenomegaly and a mass on the spleen. A malignant tumor could not be ruled out by blood and imaging tests, and splenectomy was therefore performed with laparotomy. Histopathologically, hemangiomatous nodules with a mixture of multiple vascular components were found, resulting in a diagnosis of SANT. The patient recovered and experienced no recurrence of her previous symptoms in the 18 months following the operation. Accumulation of further cases is desired to improve diagnosis and treatment for children with this extremely rare condition.

Lacrimal Gland Intravascular Micrometastasis From a Human Papillomavirus-Driven Anorectal Squamous Cell Carcinoma With a Review of Metastatic Disease to the Lacrimal Gland

To document a unique case of anorectal squamous cell carcinoma that was metastatic to the microvasculature of the lacrimal gland in a patient with human immunodeficiency virus and to review previously reported cases of metastases to the lacrimal gland. Both a retrospective chart review and comprehensive literature review were performed. The unusual histopathologic pattern of the current case was illustrated with immunohistochemical studies (CD31, D2-40, pancytokeratin, p16, and p63) and in situ hybridization studies for high-risk human papillomavirus types 16 and 18. The authors describe the first case of metastatic anorectal squamous cell carcinoma to the lacrimal gland. Only 24 cases of metastatic disease to the lacrimal gland have been reported, the majority from breast carcinomas. The metastasis did not form a macroscopic lesions, instead was composed of microscopic intravascular and intraparenchymal tumor deposits, a subtle phenomena. Immunohistochemistry confirmed the presence of the intravascular neoplastic cells. p16 served as a surrogate marker for human papillomavirus-associated squamous cell carcinoma and was confirmed with in situ hybridization for human papillomavirus 16 and 18. This testing, combined with the clinical history, defined the diagnosis and confirmed human papillomavirus as the tumor driver. Metastases to the lacrimal gland remain rare, but clinicians and pathologists alike must be attuned to the possibility of subtle microscopic foci of tumor as a pattern of metastasis in scenarios without a discrete mass-forming lesion, as this may portend a poor prognosis.

IgG4-related focal retroperitoneal fibrosis in ureter suggestive of colon cancer recurrence and resected laparoscopically: a case report

BackgroundImmunoglobulin G4-related disease (IgG4-RD) is a novel disease concept of unknown cause that is characterized by abundant infiltration of IgG4-positive cells, mass-forming lesions, and elevated serum IgG4 levels. The infiltration of IgG4-positive plasma cells and lymphocytes causes swelling, inflammation, fibrosis, and obliterative phlebitis in multiple organs. On the other hand, IgG4-RD occurring in the ureters has rarely been reported. To our knowledge, this is the first report of laparoscopic partial ureteral resection for IgG4-related focal retroperitoneal fibrosis in a ureter with suspected colon cancer recurrence.Case presentationA 72-year-old man with a history of sigmoid colon cancer visited Shiga University of Medical Science Hospital for regular follow-up in December 2019. Enhanced abdominal computed tomography revealed a mass involving the left ureter. Furthermore, fluorine-18 fluorodeoxyglucose positron emission tomography showed significant accumulation of fluorodeoxyglucose uptake in the same region. Due to the possibility of colon cancer recurrence, a laparoscopic excisional biopsy with partial ureteral resection was performed. Histologically, IgG4-positive plasma cell infiltration exceeding 10 cells per high-power field and a high ratio of IgG4-positive/IgG-positive cells exceeding 40% were observed. The postoperative serum IgG4 level was 384 mg/dL. With the application of these findings to the diagnostic algorithm in the comprehensive diagnostic criteria for IgG4-RD, the mass-forming lesion was diagnosed as definitive IgG4-related focal retroperitoneal fibrosis.ConclusionsIgG4-RD should be considered in the differential diagnosis of retroperitoneal lesions. Moreover, laparoscopic surgery may be useful for making the diagnosis in difficult-to-biopsy cases.

Immunoglobulin G4-Related Disease Mimicking Malignant Bowel Obstruction

A 40-year-old man with ankylosing spondylitis and left buccal cancer presented to our emergency department with periumbilical pain, nausea, and abdominal distention for 3 days. He denied undergoing abdominal surgery. His vital signs were normal. Physical examination showed a distended abdomen with periumbilical tenderness. Routine blood testing showed mild neutrophilic leukocytosis (white blood cell count, 10,400/μL; neutrophils, 82%). Computed tomography imaging showed a mass-forming lesion involving the ileocecal valve (Figure A, arrow).

Endoscopic ultrasound-guided fine needle aspiration of accessory spleen: Cytomorphologic features and diagnostic considerations.

Accessory spleen/or splenule (AS) can involve pancreas/or peripancreatic tissue and present as a mass-forming lesion, and on imaging studies, it stimulates concern for a neoplastic process. The current study reported the largest cohort of AS cases evaluated by endoscopic ultrasound-guided fine needle aspiration (EUS-FNA). We retrospectively reviewed our data base system for cases underwent EUS-FNA for pancreatic/or peripancreatic lesions, with "AS" in diagnosis or in note/or with a clinical concern in the history, from January 2010 to August 2019. Corresponding cytology slides were re-reviewed to identify the key cytomorphologic features. We identified 25 AS cases from 15 female and 10 male patients with a mean age of 55 years. Most patients presented with non-specific clinical symptoms or were identified as an incidental mass lesion. Majority of the lesions were located in or around the pancreatic tail region (68%) while the remainder in perisplenic region (32%). Rapid on-site evaluation (ROSE) was performed in nearly half of the cases (48%). Cytologically, AS shows a mixed population of medium to small-sized lymphocytes, clusters of lymphoid cells (LC), prominent vascularity (PV), scattered mixed inflammatory cells including eosinophils, and large platelet aggregates (LPAs). Among them, LC (P = .0079), PV and LPAs were the most helpful features for cytological diagnosis. AS is a benign entity and may pose a diagnostic challenge due to its resemblance to a neoplastic process on imaging studies. EUS-FNA is an important tool to recognize AS by identifying its key cytologic features, thus may help to avoid unnecessary surgical management.

Smooth muscle hyperplasia of the testicular adnexa: a clinicopathologic study of 12 cases

Smooth muscle hyperplasia of the testicular adnexa (SMH-TA) is a rare mass-forming intrascrotal lesion. Although benign, it can be a diagnostic challenge, as we have seen in our consult practice. Herein, we discuss our experience with these lesions over 14 years. Twelve SMH-TA cases were identified in our institutional records between 2005 and 2019. The morphologic features were reviewed. Clinical information was obtained from physicians' notes. The mean age was 51 years (range, 24-82 years). Six cases were on the left side, five on the right, and one was bilateral. The most common presentations were orchialgia (n=10) and mass (n=6). Two patients had a concurrent incarcerated inguinal hernia, and one had a recent groin trauma. Past medical history included 5 patients with previous surgeries in the inguinal region, 2 with a history of treated infections, and 1 with persistent chronic orchitis. Eight patients have undergone ultrasound imaging which showed lesions (n=4), hematoma (n=1), undescended testis (n=1), or no abnormalities (n=2). Grossly, the mean size was 1.7cm (range, 1.0-3cm). The lesions had ill-defined, focally cystic, pink-tan nodular surface. Microscopically, the lesions were comprised of an ill-defined smooth muscle proliferation arranged in fascicles or haphazard fashion, growing in a periductal, perivascular, interstitial, or most commonly in a mixed pattern. SMH-TA is a rare benign entity that can present clinically as orchialgia and/or a suspicious intrascrotal mass. As suggested in previous studies, we believe that this lesion represents a reactive process.

The role of T2*-weighted gradient echo in the diagnosis of tumefactive intrahepatic extramedullary hematopoiesis in myelodysplastic syndrome and diffuse hepatic iron overload: a case report and review of the literature

BackgroundExtramedullary hematopoiesis is the proliferation of hematopoietic cells outside bone marrow secondary to marrow hematopoiesis failure. Extramedullary hematopoiesis rarely presents as a mass-forming hepatic lesion; in this case, imaging-based differentiation from primary and metastatic hepatic neoplasms is difficult, often leading to biopsy for definitive diagnosis. We report a case of tumefactive hepatic extramedullary hematopoiesis in the setting of myelodysplastic syndrome with concurrent hepatic iron overload, and the role of T2*-weighted gradient-echo magnetic resonance imaging in differentiating extramedullary hematopoiesis from primary and metastatic hepatic lesions. To the best of our knowledge, T2*-weighted gradient-echo evaluation of extramedullary hematopoiesis in the setting of diffuse hepatic hemochromatosis has not been previously described.Case presentationA 52-year-old white man with myelodysplastic syndrome and marrow fibrosis was found to have a 4 cm hepatic lesion on ultrasound during workup for bone marrow transplantation. Magnetic resonance imaging revealed diffuse hepatic iron overload and non-visualization of the lesion on T2* gradient-echo sequence suggesting the presence of iron deposition within the lesion similar to that in background hepatic parenchyma. Subsequent ultrasound-guided biopsy of the lesion revealed extramedullary hematopoiesis. Six months later, while still being evaluated for bone marrow transplant, our patient was found to have poor pulmonary function tests. Follow-up computed tomography angiogram showed a mass within his right main pulmonary artery. Bronchoscopic biopsy of this mass once again revealed extramedullary hematopoiesis. He received radiation therapy to his chest. However, 2 weeks later, he developed mediastinal hematoma and died shortly afterward, secondary to respiratory arrest.ConclusionsMass-forming extramedullary hematopoiesis is rare; however, our report emphasizes that it needs to be considered in the initial differential diagnosis of hepatic lesions arising in the setting of bone marrow disorders. We also show that in the setting of diffuse hepatic iron overload, tumefactive extramedullary hematopoiesis appeared isointense to background liver on T2* gradient-echo sequence, while adenoma, hepatoma, and hepatic metastasis appear hyperintense. Thus, T2*-weighted gradient-echo sequence may have a potential role in the imaging diagnosis of mass-forming hepatic extramedullary hematopoiesis arising in the setting of diffuse iron overload.

IgG4-Related Disease with lymphadenopathy Presenting as a Cervical lymph node enlargement

During the course of evaluation and management of neck masses, consideration for Immunoglobulin G4-related disease (IgG4-RD) should be given. IgG4-RD is relatively a new growing entity of immune-mediated origin, characterized by a mass-forming lesion, the infiltration of IgG4-positive plasma cells and occasionally elevated serum IgG4. The most common manifestations are parotid and lacrimal swelling, lymphadenopathy and autoimmune pancreatitis.A previously healthy 72-year-old man was referred to our clinic with a 2-month history of left cervical lymph node enlargement without systemic manifestations . A cervical lymph node biopsy was planned because of elevated serum IgG4 levels. Pathological findings showed prominent infiltration of IgG4-postive plasma cells in the lymph node. After steroid therapy, a computed tomography scan revealed a decrease in the cervical lymph node size.This case illustrates the importance of including IgG4-RD in the differential diagnosis of a cervical lymph node enlargement.

Implications of Intrahepatic Cholangiocarcinoma Etiology on Recurrence and Prognosis after Curative-Intent Resection: a Multi-Institutional Study.

We sought to investigate the prognosis of patients following curative-intent surgery for intrahepatic cholangiocarcinoma (ICC) stratified by hepatitis B (HBV-ICC), hepatolithiasis (Stone-ICC), and no identifiable cause (conventional ICC) etiologic subtype. 986 patients with HBV-ICC (n=201), stone-ICC (n=103), and conventional ICC (n=682) who underwent curative-intent resection were identified from a multi-institutional database. Propensity score matching (PSM) was used to mitigate residual bias. HBV-ICC patients more often had cirrhosis, earlier stage tumors, a mass-forming lesion, well-to-moderate tumor differentiation, and an R0 resection versus stone-ICC or conventional ICC patients. Five-year recurrence-free survival among HBV-ICC and conventional ICC patients was 23.9 and 17.8%, respectively, versus a recurrence-free of only 8.3% among patients with stone-ICC. Similarly, 5-year overall survival among patients with stone-ICC was only 18.3% compared with 48.9 and 38.0% for patients with HBV-ICC and conventional ICC, respectively. On PSM, patients with stone-ICC group had equivalent long-term outcomes as HBV-ICC patients. In contrast, on PSM, stone-ICC patients had a median overall survival of only 18.0months versus 44.0months for patients with conventional ICC. Median overall survival after intrahepatic-only recurrence among patients who had stone-ICC (6.0months) was worse than OS among HBV-ICC (13.0months) or conventional ICC (12.0months) (p=0.006 and p=0.082, respectively). While HBV-ICC had a better prognosis on unadjusted analyses, these differences were mitigated on PSM suggesting no stage-for-stage differences in outcomes compared with stone-ICC or conventional ICC. In contrast, patients with stone-ICC had worse long-term outcomes. These data highlight the relative importance of ICC etiology relative to established clinicopathological factors in the prognosis of patients with ICC.

간세포암종으로 오인된 면역글로불린 G4-연관 염증 가성종양

Immunoglobulin G4-related disease is a recently recognized entity characterized by a massforming or regional lesion that contains an extensive infiltration of IgG4-producing plasma cells with dense fibrosis. Immunoglobulin G4-related disease can affect any organ system, but solitary hepatic lesion of Immunoglobulin G4-related disease is very rare. This entity mimics primary malignant hepatic tumor, such as hepatocellular carcinoma or intrahepatic cholangiocarcinoma. We experienced a case of hepatic IgG4-related inflammatory pseudotumor in a 50-year-old woman, mimicking hepatocellular carcinoma.

Pancreatic hamartoma, a rare benign disease of the pancreas: A case report.

Pancreatic hamartoma is an extremely rare, non-neoplastic, mass-forming lesion that may be mistaken for malignancy, and the pre-operative diagnosis is particularly challenging. The published literature contains only 23 cases of pancreatic hamartoma. The majority of the cases reported patients with a single benign tumor-like disease that received a pancreatectomy. Immunohistochemical findings confirmed the diagnosis following surgery. The current study reports the case of a 53-year-old female who presented to the Department of Abdominal Surgery, Chinese Academy of Medical Sciences, Cancer Hospital (Beijing, China), due to abdominal pain. Abdominal magnetic resonance imaging revealed a 22×14-mm mass in the head of the pancreas. The patient was pre-operatively diagnosed with a pancreatic space-occupying lesion, and subsequently underwent a pancreaticoduodenectomy. The post-operative course was uneventful. Histological examination of the resected lesion resulted in a diagnosis of pancreatic hamartoma. There were no signs of recurrence at 55 months post-surgery.

Healthy and tumoral tissue resistivity in wild-type and sparc-/- animal models.

Despite the technological improvement of radiologic, endoscopic and nuclear imaging, the accuracy of diagnostic procedures for tumors can be limited whenever a mass-forming lesion is identified. This is true also because bioptical sampling cannot be properly guided into the lesions so as to puncture neoplastic tissue and to avoid necrotic areas. Under these circumstances, invasive and expensive procedures are still required to obtain diagnosis which is mandatory to plan the most appropriate therapeutic strategy. In order to test if electrical impedance spectroscopy may be helpful in providing further evidence for cancer detection, resistivity measurements were taken on 22 mice, 11 wild-type and 11 sparc-/- (knock out for the protein SPARC: secreted protein acidic and rich in cysteine), bearing mammary carcinomas, by placing a needle-probe into tumor, peritumoral and contralateral healthy fat areas. Tumor resistivity was significantly lower than both peritumoral fat and contralateral fat tissues. Resistivity in sparc-/- mice was lower than wild-type animals. A significant frequency dependence of resistivity was present in tissues analyzed. We conclude that accurate measurements of resistivity may allow to discriminate between tissues with different pathological and/or structural characteristics. Therefore, resistivity measurements could be considered for in vivo detection and differential diagnosis of tumor masses.