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A class of extinct pelmatozoan echinoderms in the subphylum Crinozoa.



(or sea buds), a class of extinct invertebrate animals of the phylum Echinodermata. The body of the blastoid consisted of a crown formed by a blastoid calyx, or theca, with numerous “arms,” or brachioles, and a stem. The brachioles caught particles of food, which were directed to the mouth along sulci, or grooves, running from the brachioles to the ambulacra. Under the surface of the calyx was a system of calcareous tubes (hydrospires), which probably served for breathing. Blastoidea lived in the oceans from the Silurian to the Permian period. They were numerous in the Devonian and Early Carboniferous periods in North America and in the Permian period in Indonesia and the Ural Region. More than 300 species of Blastoidea are known. Some of them are the leading fossils of the Carboniferous and Permian periods.


Osnovy paleontologii: Iglokozhie. . . . Moscow, 1964.


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The final diagnosis was MCL, pleomorphic variant (classified under blastoid morphology by the World Health Organization classification system) with bone marrow involvement.
The blastoid types MCL are more aggressive than MCL and associated with a worse clinical outcome.
He concludes that if the ancient echinoderms had similar characteristics, snails would have been better off to treat blastoid and crinoids as long-term hosts rather than as prey.
The morphologic types of mantle cell lymphoma, including blastoid variants, are characterized by a high mitotic rate with cells resembling myeloid or lymphoid blasts.
Sequence analysis proves clonal identity in five patients with typical and blastoid mantle cell lymphoma.
B-cell malignancies include SLL/CLL, the associated Richter transformation to large B-cell lymphoma, and mantle cell lymphoma with its blastoid variant.
Mantle cell lymphoma involving skin: cutaneous lesions may be the first manifestation of disease and tumors often have blastoid cytologic features.
12,29,32] Two reports that described 100% bone marrow involvement represented cases of the leukemic phase of the blastoid variant of MCL or blastic mantle cell leukemia.