Nodal mycobacterial spindle cell pseudotumor: A diagnostic pitfall

Inflammatory pseudotumor (IPT) is a rare benign mass forming lesion that has been reported in virtually every organ, and can closely mimic spindle cell neoplasms. Mycobacterial spindle cell pseudotumor (MSP) represents a small proportion of IPT of the lymph node, which occur in immunocompromised patients, posing a diagnostic challenge. We report three cases of MSP involving two AIDS patients who presented with generalized lymphadenopathy, and one immunosuppressed patient with a mediastinal mass. Biopsy in these cases revealed effaced architecture replaced by proliferating fibrohistiocytic spindle cells, fibrosis and polymorphic inflammatory infiltrate. Inflammatory pseudotumors and other spindle cell neoplasms of the lymph node can show overlapping morphologic features, resulting in diagnostic confusion. A differential diagnosis of Mycobacterial spindle cell pseudotumor should be kept in mind when approaching localized or generalized lymphadenopathy in an immunocompromised patient.

Bovine Papillomatosis in a One-Year-Old Kedah Kelantan Cross Cattle Calf

Bovine papillomatosis is an infectious disease, characterized by the presence of multiple benign mass that can regress spontaneously or progress into malignant neoplasia caused by bovine papillomavirus. Epidermal proliferation causes the lesion to have the keratotic surface that resembles a cauliflower. In this case report, bovine papillomatosis that was encountered in a farm at UMK Bachok, Kelantan will be discussed. A year-old male Kedah Kelantan (KK) cross cattle calf was presented with a presence of multiple, circular, around 1-2cm in diameter, wart-like lesion localized on the ventral part of the mandible and on the chin. A series of diagnostic approaches had been conducted to reach the definitive diagnosis, which includes biopsy for histopathology, polymerase chain reaction (PCR) and fecal examination.

Alternative cause for hypoglycaemia in insulin-treated diabetes mellitus

We present a case of a 73-year-old woman who developed recurrent hypoglycaemia during a prolonged hospital stay following a mechanical fall. She had a complex history of insulin-treated diabetes mellitus, hypothyroidism, diffuse systemic cutaneous sclerosis, Raynaud’s disease, previous breast cancer, Barrett’s oesophagus and previous partial gastrectomy for a benign mass. Hypoglycaemia persisted despite weaning of insulin. She had no clinical features of adrenal or pituitary insufficiency with an acceptable cortisol on stopping prednisolone and had an optimal thyroid replacement. A 72-hour fast elicited hypoglycaemia with corresponding low insulin level. Although the C-peptide was detectable, there were no clinical, biochemical or radiological features suggestive of insulinoma. Reactive hypoglycaemia post partial gastrectomy was ruled out based on limited relation of the hypoglycaemia to meals and the low insulin levels. Hydroxychloroquine (HCQ)-induced hypoglycaemia was considered based on previous case reports and the recent literature, with a successful resolution of hypoglycaemia on discontinuation of HCQ.

GFAP-Negative Subcutaneous Sacrococcygeal Extraspinal Ependymoma

Ependymomas are slowly growing glial tumors derived from the ependymal cells and usually occur in the central nervous system (CNS). Ependymomas rarely occur outside of the CNS and they are called extraspinal ependymomas. In spite of their metastatic potential, extraspinal ependymomas can be misdiagnosed for other benign mass like pilonidal cysts. The diagnosis is confirmed by histopathology and most of the cases are known to show glial fibrillary acidic protein (GFAP), S-100 protein, and keratin (AE1AE3) immunoreactivity. Herein, we present a case of GFAP-negative ependymoma, which presented as asymptomatic subcutaneous tumor of the left buttock and was clinically misdiagnosed as epidermal cyst. Our case indicates that ependymomas cannot be ruled out by lack of GFAP immunoreactivity and an asymptomatic subcutaneous mass could be a malignant tumor like ependymomas, which requires careful examinations.

Paranasal Mass in a Healthy Male Toddler

Head and neck tumors are rare in pediatric patients but should be kept in the differential when a patient presents with a new swelling or mass. One of these tumors is a myxoma, which is an insidiously growing, benign mass originating from the mesenchyme. They most commonly arise in the myocardium but can also develop in facial structures, particularly in the maxilla and mandible. When arising in facial structures, ocular, respiratory, and digestive systems can be affected based on local invasion. Complete surgical resection is curative but can lead to significant morbidity as well. Here, we present a case of a 15-month-old toddler presenting with a paranasal mass, which was ultimately diagnosed as a maxillary myxoma. This tumor is very rare in the pediatric population, especially in the toddler age-group, reminding clinicians to broaden the differential diagnosis when a patient’s course is atypical.

Classical Lobular Carcinoma In Situ Arising From an Intraductal Papilloma of the Breast: A Case Report

Intraductal papilloma of the breast is a benign, mass-forming, proliferative lesion with a papillary architecture confined within a duct. Lobular neoplasia can rarely arise from an intraductal papilloma of the breast. In this article, we report the morphologic features of a rare case of classical LCIS (lobular carcinoma in situ) arising from an intraductal papilloma in a 76-year-old woman. The monomorphic dyscohesive cells were present between the myoepithelial and luminal epithelial layer in the periphery of the papilloma. These cells partially obliterated the spaces between the papillae forming solid sheets. The monomorphic dyscohesive cells showed lack of E-cadherin expression and uniform staining for estrogen receptor. We review the histologic differential diagnosis and stress the importance of correct classification to ensure optimal care for patients. We also propose a new criterion for the distinction of lobular neoplasia within a papilloma.

Do Benign Mass Lesions in the Superficial Lobe of Parotid Gland Influence Landmark-Based Search for Facial Nerve Trunk at Surgery?

Objective: To assess the influence of benign mass lesions in the superficial lobe of parotid on the known anatomic landmarks for identifying the facial nerve trunk. Method: Patients with unilateral biopsy-proven benign mass lesions in the superficial parotid were selected for this observational study. During superficial/partial superficial parotidectomy, distance of the facial nerve trunk from each landmark was assessed using spring calliper and correlated with the lesion’s volume (measured from the pre-operative imaging). At least two identifiers among tragal pointer (TP), posterior belly of digastric muscle (PBDM) and tympanomastoid suture (TMS) were considered. Results: The study involved 32 patients. The lesions mostly involved the parotid tail (50%) and pretragal region (34.3%), and constituted of pleomorphic adenoma (~66%) and Warthin’s tumor (~9%), the rest being various cysts and hamartomas. TP was universally uncovered, while PBDM and TMS were exposed in 26 and 25 patients, respectively. Average distances between the facial nerve trunk and TP, PBDM and TMS were 12.79 mm (SD=2.33), 9.78 mm (SD=1.21) and 7.58 mm (SD=1.33), respectively. Correlation coefficients between the lesion’s volume and the distance of facial nerve from a given landmark were -0.11, 0.04 and -0.16 for TP, PBDM and TMS, respectively. Conclusions: TP was the most easily available landmark on surgical dissection, while PBDM was the most consistent and the least variable when volumetric data of the benign mass lesions in the superficial lobe of parotid were considered as a factor influencing the distance from the facial nerve trunk.

Diagnostic Value of the Microbiome in the Bronchoalveolar Fluid of Patients with Lung masses and its Relationship with their Clinical Features

Background: Bacterial communities were demonstrated to be correlated with patients with several respiratory diseases. Although some studies have been performed on the composition of the microbiota in lung cancer, the issue has not been fully addressed. Therefore, we characterized the microbiomes of patients with lung cancer and benign mass-like lesions and evaluated the relationship between microbiota and clinical features.Methods: Bronchoalveolar fluid of patients with lung masses was collected and analyzed by 16S rRNA-based next-generation sequencing. Then, the relationships between the composition of the microbiota and clinical features were evaluated. Results: The relative abundance of two genera, Megasphaera and Norank_p_saccharibacteria, and two phyla, Firmicutes and Saccharibacteria, were significantly increased, while one phyla Proteobacteria was decreased in patients with lung cancer. The genera Atoprevotella and 1 phylum, Bacteroidetes, were increased in patients with SCLC, while 1 phylum, Chloroflexi, was more abundant in patients with NSCLC than those with SCLC. Moreover, the patients whose BALF was enriched with the genus Capnocytophaga seemed to have a better response to cisplatin-based chemotherapy. The area under the curve of a combination of two genera (megasphera and norank_p_Saccharibacteria) used to predict lung cancer was 0.803. The area under the curve of the genus Capnocytophaga in predicting the response to chemotherapy was 0.850.Conclusions: There are differences in the composition of the microbiome of patients with lung cancer and those with benign mass-like lesions. The lung microbiota may be used as a biomarker for diagnosing lung cancer and differentiating the cancer subtype and might have an impact in the response to cisplatin-based chemotherapy among patients with lung cancer.

Histologic Correlation of Breast Biopsies Presenting as Non-Mass Enhancing Lesions on Magnetic Resonance Imaging: A Contemporary Single Institutional Series

Introduction/Objective Non-mass enhancement (NME) in breast tissue is an area of enhancement on MRI that appears distinct from background breast parenchyma, but lacks definitive features of a mass. NME is characterized by its internal enhancement pattern and distribution, and can represent benign, high risk, or malignant pathology. Given this considerable overlap, a core biopsy is often necessary for diagnosis and management. We aimed to elucidate the most frequent histologic findings found on breast biopsies for MRI NME. Methods Using our institutional database we identified 70 female patients with high risk status for breast cancer with MRI screen detected NME (BIRADS-4-suspicious for malignancy) that underwent subsequent biopsy procedure during the period of 01/2016-12/2017. Primary pathologic diagnoses were subcategorized as follows: malignant, atypical, benign mass-like lesions, fibrocystic changes (proliferative, nonproliferative), or “other” primary diagnoses. Results The median age of patients was 48 years (range: 22-76 years). Of the 70 patients, 66 underwent MRI-guided core biopsy, 3 underwent ultrasound-guided core biopsy and 1 underwent excisional biopsy. The primary diagnosis was analyzed. Of these 70 cases, 8 (11.4%) were malignant (7 with ductal carcinoma in situ and 1 with invasive ductal carcinoma), 1 (1.4%) had atypical lobular hyperplasia, and the remaining 61 (87.1%) showed benign findings (36 with fibrocystic changes (FCC), 22 benign mass-like lesions, 3 with other non-specific findings). The FCC were subcategorized as proliferative (usual ductal hyperplasia, columnar cell change, incidental radial scar, incidental intraductal papilloma, sclerosing adenosis, focal pseudoangiomatous stromal hyperplasia (PASH)) or nonprolifeative (stromal fibrosis, duct ectasia, apocrine metaplasia). Majority (61.1%) of FCC were both proliferative and nonproliferative, 22.2% proliferative only and 16.7% nonproliferative only. Benign mass-like lesions included PASH (45.4%), fibroadenomatoid nodule (22.7%), fat necrosis (18.2 %) and remaining had the diagnosis of clustered apocrine cysts, papillomatosis, and radial sclerosing lesion. Conclusion Less than a third of cases showed malignant findings and more than two-third of cases showed benign findings with a high rate of detection of proliferative lesions and PASH.