Limb–girdle muscular dystrophy (LGMD) is a genetically heterogeneous group of rare muscular dystrophies that share a set of clinical characteristics. It is characterised by progressive muscle wasting which affects predominantly hip and shoulder muscles. LGMD usually has an autosomal pattern of inheritance. It currently has no known cure or treatment. Signs and symptoms
By definition, all limb girdle muscular dystrophies (LGMD) cause progressive proximal weakness, meaning weakness of the muscles on or close to the torso that worsens over time. Explicitly, LGMD preferentially affects muscles of the hip girdle, thigh, shoulder girdle, and/or upper arm. The muscle weakness is generally symmetric. Usually, the hip girdle is the first area to exhibit weakness, manifesting as difficulty walking, going up and/or down stairs, rising from a chair, bending at the waist, or squatting. Because of these difficulties, falling can occur frequently. Weakness of the shoulder girdle can make lifting objects, or even elevating the arms, difficult or impossible. Rate of progression varies between patients. Eventually, the abilities to run and walk can deteriorate. The disease commonly leads to dependence on a wheelchair within years of symptom onset, although some patients maintain mobility. Eventually the disease can affect other muscles such as the ones located in the face. By definition, LGMDs primarily affect skeletal muscles, although cardiac muscle can be affected to a lesser degree in select subtypes, which can cause palpitations
There can be significant variability in disease features and severity between LGMD subtypes, and even within any given LGMD subtype.
In 2006 the US FDA approved (imatinib mesylate) for the treatment of DFSP. As is true for all medicinal drugs that have a name that ends in "ib," imatinib is a small molecular pathway inhibitor; imatinib inhibits tyrosine kinase. It may be able to induce tumor regression in patients with recurrent DFSP, unresectable DFSP, or metastatic DFSP. There is clinical evidence that imatinib, which inhibits PDGF-receptors, may be effective for tumors positive for the t(17;22) translocation. It is suggested that imatinib may be a treatment for challenging, locally advanced disease and in the rare metastatic cases It was approved for use by adult patients with unresectable, recurrent and/or metastatic dermatofibrosarcoma protuberans (DFSP). Metastatic disease
Distant hematogenous metastases are extremely rare. Metastases to regional lymph nodes are rarer and are most likely in patients who have had multiple local recurrences after inadequate surgical resection. Repeatedly recurring tumors have an increased risk for transformation into a more malignant form (DFSP-FS). The lungs are most frequently affected, but metastases to the brain, bone, and other soft tissues are reported. Studies
DFSP is not extensively studied due to its rarity and low mortality. The majority of studies are small size case studies or meta-analysis. The most extensive research study to date was Perspectives of Patients With Dermatofibrosarcoma Protuberans on Diagnostic Delays, Surgical Outcomes, and Nonprotuberance. The lead researcher Jerad Gardner spoke at a Ted Talk in February 2020 on the topic. History
Taylor, RW, in 1890. first identified DFSP as a keloid sarcoma.