[Circular resection of the thoracic trachea for MALT lymphoma in an 81-year-old patient]. / Tsirkulyarnaya rezektsiya grudnogo otdela trakhei pri MALT-limfome u patsientki v vozraste 81 goda.

A rare clinical observation of primary tracheal MALT lymphoma is reported and difficulties of differential diagnosis are discussed. Tracheal neoplasms are rare tumors and characterized by delayed diagnosis after clinical manifestation (tracheal stenosis and associated complications). These tumors often occur an advanced age patients that complicates examination and surgical treatment. High risk is determined by type of surgery, possible postoperative complications and senile age.

[Biphasic (dedifferentiated) osteosarcoma of the lung in the light of current ideas on biphasic tumors]. / Bifaznaia ('dedifferentsirovannaia') osteosarkoma legkogo v svete sovremennykh predstavlenii o bifaznykh opukholiakh.

The paper presents a case of biphasic (dedifferentiated) osteosarcoma arising primarily on the lung, which has not previously encountered in the literature. It provides a detailed description of its clinical, instrumental, and morphological pattern. It also analyzes the literature on the study of primary pulmonary osteosarcoma and extraskeletal osteosarcoma with high-grade transformation. This clinical case is a clear example of classic biphasic sarcoma interpreted in the context of the phenomenon of biphasic tumors. Their most important aspects (terminology, morphology, biological behavior, and a mechanism of dedifferentiation) are highlighted; the key characteristics of biphasic sarcomas are listed.