Dissecting a diagnostic enigma: Hypertension in a young patient from an organ of Zuckerkandl paraganglioma

Hypertension in young patients can mask rare conditions like paragangliomas, especially in the absence of conventional symptoms. A comprehensive diagnostic evaluation and multidisciplinary approach are crucial for optimal management and outcomes.

Rapid Development of Syringocystadenocarcinoma Papilliferum in an Immunosuppressed Liver Transplant Recipient

Syringocystadenocarcinoma papilliferum (SCACP) is a rare cutaneous adnexal neoplasm. To the best of our knowledge, fewer than 50 cases have been described in the literature. We describe the first reported case of an SCACP in an immunocompromised patient. We report the development of an SCACP over 3 months in a 77-year-old organ transplant recipient undergoing regular dermatological follow-up. The lesion was excised with clear margins with Mohs micrographic surgery. This lesion's rapid development and small size contrasts with the predominantly slow-growing, larger lesions described in immunocompetent patients. Lastly, this case further highlights the importance of close dermatological follow-up of immunosuppressed patients.

H2A.B is a cancer/testis factor involved in the activation of ribosome biogenesis in Hodgkin lymphoma

Testis-specific regulators of chromatin function are commonly ectopically expressed in human cancers, but their roles are poorly understood. Examination of 81 primary Hodgkin lymphoma (HL) samples showed that the ectopic expression of the eutherian testis-specific histone variant H2A.B is an inherent feature of HL. In experiments using two HL cell lines derived from different subtypes of HL, H2A.B knockdown inhibited cell proliferation. H2A.B was enriched in both nucleoli of these HL cell lines and primary HL samples. We found that H2A.B enhanced ribosomal DNA (rDNA) transcription, was enriched at the rDNA promoter and transcribed regions, and interacted with RNA Pol I. Depletion of H2A.B caused the loss of RNA Pol I from rDNA chromatin. Remarkably, H2A.B was also required for high levels of ribosomal protein gene expression being located at the transcriptional start site and within the gene body. H2A.B knockdown reduced gene body chromatin accessibility of active RNA Pol II genes concurrent with a decrease in transcription. Taken together, our data show that in HL H2A.B has acquired a new function, the ability to increase ribosome biogenesis.

Updates in the molecular pathology of non-small cell lung cancer

An understanding of the molecular pathology of non-small cell lung cancer (NSCLC) is important for pathologists as molecular characterization is now required for treatment decisions in advanced stage disease. While assessment for EGFR mutations, ALK and ROS1 fusions, and in some countries BRAF mutations, is now standard practice, other oncogenic mutations are also emerging that may impact routine clinical practice including alterations involving KRAS, NTRK, RET, MET and HER2. In addition, molecular pathology alterations of NSCLC are associated with responses to immune checkpoint therapy and are being increasingly investigated. Finally, specific molecular pathological alterations define some rarer subtypes of NSCLC such as salivary gland tumours, NUT carcinoma and SMARCA4-deficient undifferentiated tumour, and an understanding of the molecular pathology is important for their accurate diagnosis. In this review, the molecular pathology of NSCLC is discussed with a focus on clinically relevant molecular alterations.

A case of an asymptomatic sacrococcygeal teratoma diagnosed in adulthood

Sacrococcygeal teratomas are rare congenital tumours that are even more uncommon when present in adulthood. They are derived from residual stem cells in the presacral space that differentiate into clusters of somatic cell. We present the diagnosis, management and post-operative follow-up in a 37-year-old gentleman referred to our department with an incidental finding of a lobulated presacral cystic mass on computed tomography imaging. Magnetic resonance imaging and fluorodeoxyglucose (FDG)-positron emission tomography (PET) scans were performed to further characterize the lesion. The decision was then made for surgical excision and the specimen along with the coccyx was retrieved en-bloc via a trans-sacral surgical approach. Histopathology of the mass uncovered the presence of squamous, respiratory and prostatic epithelium consistent with the diagnosis of a sacrococcygeal teratoma.