WD Repeat Domain 1 (WDR1) Deficiency Presenting as a Cause of Infantile Inflammatory Bowel Disease.

Infantile and very early onset inflammatory bowel disease (VEOIBD) are a rare phenomenon wherein patients develop intestinal inflammation with typical IBD symptoms before ages 2 and 6, respectively. In recent years, there has been an increasing number of monogenetic immunological disorders identified that lead a child to develop VEOIBD. We present a case of an infant boy who presented with hematochezia and thrombocytopenia in the first week of life and developed IBD by the age of 1 month. Additional clues to his diagnosis included lymphopenia and nuclear herniation observed in his neutrophils. Compound heterozygous damaging variants were identified in WD Repeat Domain 1 (WDR1) by whole-exome sequencing (WES) and represents a novel cause of VEOIBD. Our patient's IBD and immunologic phenotype was successfully treated by hematopoietic stem cell transplant (HSCT).

Combined Tumors in Hematolymphoid Neoplasms: Case Series of Histiocytic and Langerhans Cell Sarcomas Arising From Low-Grade B-Cell Lymphoma.

We report an index case of histiocytic sarcoma arising in a 70-year-old patient with long-standing chronic lymphocytic leukemia/small lymphocytic lymphoma (CLL/SLL). The patient presented in 2017 with painful, enlarging swelling of the left neck. He had remote history of cutaneous squamous cell carcinoma with no sign of recurrence, and his CLL/SLL was thought to be in remission. Computed tomography showed mild splenomegaly and multifocal lymphadenopathy including a 3-cm left neck mass. Biopsy of the left neck mass showed CLL/SLL with associated histiocytic sarcoma. Flow cytometry demonstrated a B cell neoplasm with CLL/SLL phenotype. Despite radiation therapy, he expired 3 months after presentation. Two similar cases (CLL/SLL and histiocytic sarcoma, follicular lymphoma and Langerhans cell sarcoma) from another institution are also illustrated. The pathological features of combined tumors in lymphoid neoplasms, a general framework to the work-up to determine interrelatedness of tumor components, and the clinical relevance are discussed.

Primary squamous cell carcinoma of the distal hallux.

Squamous cell carcinoma is a common disease of cutaneous tissue with a great ability to form metastases. Squamous cell carcinoma is found most commonly on sun-damaged skin and has a rare occurrence on the toes and feet. The patient was a 68-year-old woman who was seen at a podiatric specialty office with a complaint of pain in her left great toe and toenail. Radiographs displayed erosion of the distal hallux, and magnetic resonance imaging revealed no further spread of disease in the proximal phalanx. An amputation was performed of the hallux interphalangeal joint, and pathology confirmed squamous cell carcinoma of the verrucous type.

A B-cell lymphoma diagnosed in "floater" tissue: implications of the diagnosis and resolution of a laboratory error.

Contamination of a paraffin-embedded tissue block with another patient's tissue can lead to an incorrect diagnosis. We report the use of short tandem repeats for the analysis of DNA extracted from microdissected tissue from unstained slides prepared from a decalcified block from a 33-year-old woman who was previously diagnosed with a low-grade B-cell lymphoma. This diagnosis was based on a single fragment of tissue found among bone fragments taken during orthopedic surgery at a referring hospital. Our results confirm that the B-cell lymphoma tissue was not derived from our patient. Furthermore, we suggest that in cases for which the definitive identification of a tissue contaminant can resolve clinically, therapeutically, and prognostically significant questions, short tandem repeat analysis of DNA derived from microdissected surgical pathology samples should be considered to minimize errors and enhance the quality of care.

Delayed occurrence of multiple spinal drop metastases from a posterior fossa choroid plexus papilloma. Case report.

Choroid plexus papilloma is a benign central nervous system tumor that occasionally spreads along the subarachnoid space. The authors report the case of a 49-year-old man who presented with back pain 19 years after resection of a posterior fossa choroid plexus papilloma. Magnetic resonance imaging revealed multiple spinal lesions without any residual or recurrent intracranial tumor. All spinal lesions were resected and histologically diagnosed as atypical choroid plexus papilloma. The authors suggest that patients in whom choroid plexus papilloma is diagnosed should undergo total neuraxis imaging at the time of initial diagnosis as well as periodic follow-up examinations after resection to rule out drop metastases.

Differential gene expression in anaplastic lymphoma kinase-positive and anaplastic lymphoma kinase-negative anaplastic large cell lymphomas.

Anaplastic large cell lymphoma (ALCL) is an aggressive large T- or null-cell lymphoma. Most ALCLs arising in children and young adults express a constitutively active receptor tyrosine kinase, anaplastic lymphoma kinase (ALK). Anaplastic large cell lymphomas lacking ALK are clinically heterogeneous and their pathogenesis is unknown. This study is the first complementary DNA (cDNA) microarray analysis using RNA extracted from tumor tissue (7 ALK+ ALCLs and 7 ALK- ALCLs) to identify genes differentially expressed or shared between the ALK+ and ALK- tumors. Unsupervised hierarchical clustering using the top 11 most statistically significant discriminator cDNAs correctly grouped all ALK+ and ALK- tumors. Hierarchical clustering analysis using the 44 cDNAs with the greatest differential expression between ALK+ and ALK- RNAs grouped 6 of 7 ALK+ ALCLs together and 1 ALK+ ALCL with the ALK- group. In general, ALK+ tumors overexpress genes encoding signal transduction molecules (SYK , LYN , CDC37) and underexpress transcription factor genes (including HOXC6 and HOX A3 ) compared with the ALK- group. Cyclin D3 was overexpressed in the ALK+ group and the cell cycle inhibitor p19INK4D was decreased in the ALK- group, suggesting different mechanisms of promoting G 1 /S transition. Both groups had similar proliferation rates. Genes highly expressed in both ALK- and ALK+ ALCLs included kinases (LCK, protein kinase C, vav2, and NKIAMRE) and antiapoptotic molecules, suggesting possible common pathogenetic mechanisms as well.