The histological of this disease may overlap with and be difficult to distinguish from other CD30-positive T-cell lymphomas or the nodular sclerosis form of Hodgkin lymphoma. Cases in which ALK-negative ALCL is not distinguishable from the latter lymphomas are best diagnosed as peripheral T-cell lymphoma not otherwise specified (PTL, NOS). The histology of ALK-negative ALCL may also overlap with tumors of non–T-cell lineage such as various carcinomas. The differential diagnoses of ambiguous cases may be helped by examining the tumor cells for the expression of certain marker proteins. For example, expression of CD56, MUC1 (also termed EMA for epithelial membrane antigen), and clusterin and strong uniform expression of CD30 support the diagnosis of ALK-negative ALCL over PTL, NOS, while variable CD30 expression and extensive expression of T-cell receptor proteins favor PTCL-NOS over ALK-negative ALCL. Detection of certain gene abnormalities (see next section) may also help distinguishing these diseases. Gene and molecular abnormalities
ALK-negative ALCL tumor cells show products made by chimeric genes: DUSP22-IRF4 (many of which are fused at particular site and termed DUSP22-FRA7H) in 30% of the cases; TP63-TBL1XR1 in 8% of cases; and NFKB2-ROS1, NCOR2-ROS1, NFKB2-TYK2, or PABPC4-TYK2 in rare cases. They also show mutations in the JAK1 and/or STAT3 genes in 18% of cases; the MSC gene in 15% of cases, and the NOTCH1 gene in 15% of cases. About 24% of cases have a truncated ERBB4 gene. DUSP22 gene rearrangements have been associated with favorable outcomes in ALK-negative ALCL while TP63 gene arrangements are often associated with a poorer prognosis in various cancers.
The calf (PL: calves; Latin: sura) is the back portion of the lower leg in human anatomy. The muscles within the calf correspond to the posterior compartment of the leg. The two largest muscles within this compartment are known together as the calf muscle and attach to the heel via the Achilles tendon. Several other, smaller muscles attach to the knee, the ankle, and via long tendons to the toes. Etymology
From Middle English calf, kalf, from Old Norse kalfi, possibly derived from the same Germanic root as English calf ("young cow"). Cognate with Icelandic kálfi ("calf of the leg"). Calf and calf of the leg are documented in use in Middle English circa AD 1350 and AD 1425 respectively.Historically, the absence of calf, meaning a lower leg without a prominent calf muscle, was regarded by some authors as a sign of inferiority: it is well known that monkeys have no calves, and still less do they exist among the lower orders of mammals. Structure
The calf is composed of the muscles of the posterior compartment of the leg: The gastrocnemius and soleus (composing the triceps surae muscle) and the tibialis posterior. The sural nerve provides innervation. Clinical significance
Medical conditions that result in calf swelling among other symptoms include deep vein thrombosis compartment syndrome, Achilles tendon rupture, and varicose veins. Idiopathic leg cramps are common and typically affect the calf muscles at night. Edema also is common and in many cases idiopathic.