Bronchiolar adenomas (BA) - A detailed radio-pathologic analysis of six cases and review of literature.

Bronchiolar adenomas (BAs)/ciliated muco-nodular papillary tumors (CMPTs), are small, peripheral lung nodules arising predominantly in the elderly that follow a benign course. They can be mistaken for adenocarcinomas on frozen section. Immunohistochemistry (IHC) for basal cell markers highlights the continuous layer of basal cells underlying the tumor cells in BAs. BAs are further subdivided into proximal-type and distal type. Six BAs were retrieved from the pathology archives. The cases were classified based on morphology into proximal and distal BAs. The clinical and radiological features were reviewed. Immunohistochemistry and special stains were performed. The most common radiological picture of BA/CMPT was of a solid nodule with SUVmax < 3 as seen in 60% cases. 40% cases showed cavitation on CT. On histological examination, four cases were morphologically classified as proximal BAs and two as distal BAs. In proximal BAs, TTF1 was focally positive only in the basal cells in three of four. The mucin stained acidic. In distal BAs, TTF1 was diffusely positive in both basal and luminal cells. There was scant intracellular neutral mucin. Both the distal BAs had concomitant neuroendocrine tumors in the same lobe. Though the number of cases evaluated in this study is too low to be statistically significant, this study provides additional evidence to the concept of BA classification based on site specific histology and supplementary immunohistochemistry and reiterates the radiological features that may help distinguish it from malignant lesions.

Primary Histiocytic Sarcoma in Adult Polycystic Kidney Disease: Case Report and Review of Literature.

Genetically driven tissue destruction followed by remodeling in adult polycystic kidney disease (APKD) raises the possibility of malignant transformation. Renal cell carcinoma (RCC) associated with APKD has been frequently reported in the literature; however, only a few cases of nonepithelial neoplasms arising in APKD have been described so far. Histiocytic sarcoma (HS) is a lymphohematopoietic malignant neoplasm that accounts for less than 1% of hematologic malignancies. In this article, we describe a case of primary HS occurring in a 61-year-old man with end-stage renal disease secondary to APKD. This is the first reported case of primary HS in the setting of APKD. The aberrant h-caldesmon expression seen in this case is another novel finding that has previously not been described. This case highlights the importance of morphology in guiding diagnostic workup and reiterates the necessity of maintaining a high index of suspicion for neoplastic entities in APKD.

Lost in the Clinics and Found in the Morgue: A Case of Peripheral T-cell Lymphoma Masquerading as Pneumonia.

In modern medicine, there is an increasing dependence on noninvasive imaging modalities, for diagnosis and management of diseases. Though there are definite advantages to this, they are at times offset by diagnostic pitfalls especially in entities with elusive clinical presentation.Peripheral T-cell lymphoma-not otherwise specified (PTCL-NOS) is an aggressive subtype of T-cell lymphomas that does not meet criteria for a specific subtype. Peripheral T-cell lymphoma usually has varied clinical presentations depending on the site of involvement. Vast majority of PTCL patients present with systemic disease, generalized lymphadenopathy and constitutional symptoms. Pulmonary involvement is relatively rare and is seen in approximately 10% of patients.Here in we highlight a rare case of PTCL, masquerading as pneumonia due to extensive pulmonary involvement that went undiagnosed and was discovered at autopsy. This case of malignant lymphoma of T-cell origin involving the lung, which is very rare, highlights the continued importance of medical autopsies not only as a teaching tool but also as an important adjunct to investigative medicine in uncovering lapses that can subsequently be avoided to improve patient care and decrease mortality.

Paraduodenal Pancreatitis: A Deceptive Abdominal Mass with Unique Histologic Findings.

Paraduodenal pancreatitis (PP) is an uncommon abdominal pathology characterized by scarring of the pancreaticoduodenal space. Diagnosis of this inflammatory process is challenging as its clinical presentation is similar to that of pancreatic cancer. Currently, no definitive radiologic or pathologic features have been established to permit diagnosis of PP without surgical resection. However, the presence of eosinophilic concretions has been reported with increasing frequency in the histologic evaluation of PP. To the best of our knowledge, these concretions are distinctive for PP and not reported in neoplasms commonly involving the pancreaticoduodenal space. Herein, we discuss the case of a 60-year-old man who was found to have PP after pancreaticoduodenectomy for a paraduodenal mass with an initially nondiagnostic biopsy. Retrospective review of the preoperative FNA samples revealed eosinophilic concretions like those found in the final surgical specimen. If the identification of eosinophilic concretions in a background of inflammatory changes was to be accepted as a diagnostic criterion for PP, patients such as ours could be spared the morbidity associated with surgical resection.

Tracheal agenesis with esophageal atresia: an autopsy case report of a variant incompatible with life.

Background: Tracheal agenesis/atresia (TA) presents with respiratory distress at birth and subsequent difficulty in endotracheal intubation. The antenatal course is complicated by polyhydramnios and premature labor. Case report: We present a newborn baby boy with respiratory distress and unsuccessful intubation. Postmortem neck dissection revealed tracheal atresia with esophageal atresia and high tracheoesophageal fistula. Conclusion: In this variant of tracheal atresia, the coexistent esophageal atresia precluded the establishment of a functional air passage. This variant that does not fall into the any of the described categories in accepted classification systems. The lack of any distal communication makes this case inoperable and fatal.

Prostatic carcinoma with neuroendocrine differentiation harboring the EWSR1-FEV fusion transcript in a man with the WRN G327X germline mutation: A new variant of prostatic carcinoma or a member of the Ewing sarcoma family of tumors?

Since the discovery of the TMPRSS2-ERG fusion transcript in prostatic carcinoma (PCa) more than ten years ago, a long list of recurrent genomic rearrangements involving other transcription factors of the ETS family has been described. Fusions of ETS with the EWSR1 partner gene define many members of the Ewing family of tumors, including primitive neuroectodermal tumor (PNET). Although the expression of EWSR1 appears to be necessary for the oncogenic effects of ETS factors, the EWSR1-ETS rearrangement has never been reported in PCa. Herein, we discuss the pathologic diagnosis of a prostatic tumor in a 44 year-old man, recently treated with finasteride, with the EWSR1-FEV fusion (exon 7: exon 2, join in-frame) discovered by RNA-sequencing and fluorescence in situ hybridization. The tumor was morphologically and immunophenotypically equivocal for a Ewing sarcoma/PNET, and most consistent with a PCa with neuroendocrine differentiation. The patient's family history of PCa led to germline mutation testing by next-generation sequencing showing heterozygosity for the WRNG327X mutation. The WRN protein along with ATM, BRCA1, BRCA2, and RAD51 among others, comprise a DNA repair system by homologous recombination, and its alterations are associated with forms of hereditary PCa. We dispute whether the detection of EWSR1-FEV mandates one to diagnose the patient's tumor as a member of the Ewing sarcoma family.

Primary sebaceous carcinoma of the male breast: Case report and review of literature.

Primary sebaceous carcinoma of the breast is an exceedingly uncommon neoplasm that is defined as primary invasive carcinoma of the breast with sebaceous differentiation in more than 50% of cells. All confirmed cases have been reported in women. Herein, we report the case of a 70-year-old man with a primary sebaceous breast carcinoma, the first unequivocal case to be reported thus far in a man.

Pontocerebellar Hypoplasia Maps to Chromosome 7q11.23: An Autopsy Case Report of a Novel Genetic Variant.

Pontocerebellar hypoplasias are a group of autosomal recessive neurodevelopmetal disorders with varied phenotypic presentations and extensive genetic mutational landscape that are currently classified into ten subtypes. This classification is based predominantly on the genetic iterations as the phenotypic presentations are often broad and overlapping. Pontocerebellar hypoplasia type-3 (PCH3) is an autosomal recessive disorder characterized by a small cerebellar vermis, hyperreflexia, and seizures, described in Middle Eastern families in association with a homozygous truncating mutation of the PCLO gene in locus 7q11-21. This is a case of PCH, with previously unreported novel genetic alterations. The patient is a 1-week-old girl, born at term to a 26-year-old G4P0A3 woman in a nonconsanguinous relation. At birth, the baby was depressed and hypertonic with abnormal tonic-clonic movements of extremities. MRI revealed cerebellar and brainstem hypoplasia. Postmortem examination revealed a palmar simian crease. The cerebellum measured 2.5 cm from side to side and 1 cm from rostral to caudal. The vermis was rudimentary. Sectioning revealed a flattened linear fourth ventricle, scant abortive cerebellar foliae, and a markedly small cerebellum when compared with the cerebrum and with age-matched size. H&E-stained sections of cerebellum revealed scant rudimentary foliae. A rudimentary unilateral embolliform nucleus was identified. The remaining cerebellar nuclei were absent. Chromosomal microarray showed an interstitial duplication of 841 kB on chromosome 7q11.23. Locus 7q11.23 contains FGL2 and GSAP genes and is 5 MB upstream of the 7q11-21 region, suggesting a possible linkage. This novel genomic finding possibly represents a new familial variant of PCH closely associated with PCH-3 and further strengthens its association with the 7q11 locus.

Osteosarcoma presenting with malignant pleural effusion in a 55 year old.

Osteosarcoma is the most common primary malignant neoplasm of the bone with over 60% of the cases occurring in patients 10-20 years old. Osteosarcoma rarely occurs in patients older than 40 years of age, most commonly in bones affected by preexisting conditions such as Paget's disease, prior irradiated bone or osteogenesis imperfecta. Osteosarcoma presenting with pleural metastases is very rare. Herein we describe a case of metastatic osteosarcoma presenting with pleural effusion due to underlying pleural metastases in a 55 year old woman.