Genetic mutations thought to be involved in the development and/or progression of the latter disease include the L265P mutation in the MYD88 gene found in >90% of Waldenström macroglobulinaemia patients as well as various mutations in the CXCR gene found in 27% to 40% of Waldenström macroglobulinaemia patients.The clonal plasma cells involved in plasma cell dyscrasias exhibit a high degree of genetic instability. For example, the clonal plasma cell population formed by initial genetic alterations that lead to multiple myeloma contains cells that develop further genetic changes that enhance their survival, proliferation, tissue-injuring, and metastatic capacities. This allows the new cell clones to crowd out older cell clones and thereby  establish a more malignant disease. Repetition of such genetic changes underlie the evolution of a clinically silent plasma cell dyscrasia to an overt malignancy. The progressive genetic changes in clonal plasma cells include accumulating numerous single nucleotide polymorphisms, increases and decreases in gene and chromosome copy numbers, and chromosomal translocations. Genes affected include those regulating genome stability itself (e.g. KIF2B) as well as cellular activation, proliferation, and apoptosis (e.g. CIDEC, TP52, ATM, KRAS, NRAS, Wnt, and NF-κB).
Infections
Bacterial, viral, and protozoal infections may occur in the area surround the rectum. These may be the result of a sexually transmitted disease. Other
Hemorrhoids or rectal foreign body. References


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