Fig. 12.20 Hodgkinlymphoma—lymphnode.AbinucleateReed-Sternbergcellwithlarge,inclusion-likenucleoliandabundantcytoplasmissurroundedbylymphocytes,macrophages,andaneosinophil.(Courtesy of Dr. Robert W. McKenna, Department of Pathology, University of Texas Southwestern Medical School, Dallas,Texas.)
Classification. Five subtypes of Hodgkin lymphoma are recognized: (1) nodular sclerosis, (2) mixed cellularity, (3) lymphocyte rich, (4) lymphocyte depletion, and (5) lymphocyte predominant. In the first four subtypes the RS cells share certain morphologic and immunophenotypic features (described later), leading some researchers to lump together these entities under the rubric classical Hodgkin lymphoma. The lymphocyte predominant type is set apart by the expression of germinal center B cell markers by the RS cells. This subtype and the two most common forms of classical Hodgkin lymphoma, the nodular sclerosis and mixed-cellularity types, are discussed next.
Fig.12.20 ),averylargecell(15to45µmindiameter)withanenormousmultilobatenucleus,exceptionallyprominentnucleoli,andabundant,usuallyslightlyeosinophilic,cytoplasm.Particularlycharacteristicarecellswithtwo mirror-image nuclei or nuclear lobes, each containing a large (inclusion-like) acidophilic nucleolus surrounded by a clear zone,featuresthatimpartanowl-eyeappearance.TypicalRScellsandvariantshaveacharacteristicimmunophenotype,astheyexpressCD15andCD30andfailtoexpressCD45(leukocytecommonantigen),Bcellantigens,andTcellantigens.Asweshallsee,“classic”RScellsarecommoninthemixed-cellularitysubtype,uncommoninthenodularsclerosissubtype,andrareinthelymphocyte-predominancesubtype;intheselattertwosubtypes,othercharacteristicRScellvariantspredominate.
Nodular sclerosis Hodgkin lymphoma isthemostcommonform.Itisequallyfrequentinmenandinwomenandhasastrikingpropensitytoinvolvethelowercervical,supraclavicular,andmediastinallymphnodes.Mostpatientsare http://ebooksmedicine.net
Fig. 12.22 Hodgkinlymphoma,nodularsclerosistype—lymphnode.Alow-powerviewshowswell-definedbandsofpink,acellularcollagenthathavesubdividedthetumorcellsintonodules.(Courtesy of Dr. Robert W. McKenna, Department of Pathology, University of Texas Southwestern Medical School, Dallas,Texas.)
Fig. 12.21 Hodgkinlymphoma,nodularsclerosistype—lymphnode.Adistinctive“lacunarcell”withamultilobednucleuscontainingmanysmallnucleoliisseenlyingwithinaclearspacecreatedbyretractionofitscytoplasm.Itissurroundedbylymphocytes.(Courtesy of Dr. Robert W. McKenna, Department of Pathology, University of Texas Southwestern Medical School, Dallas,Texas.) adolescentsoryoungadults,andtheoverallprognosisisexcellent.Itischaracterizedmorphologicallybythefollowing:
Fig.12.21 ),aparticularRScellvariantthathasasinglemultilobatenucleus,multiplesmallnucleoli,andabundant,pale-stainingcytoplasm.Insectionsofformalin-fixedtissue,thecytoplasmoftenistornaway,leavingthenucleuslyinginanemptyspace(alacune).TheimmunophenotypeoflacunarvariantsisidenticaltothatofotherRScellsfoundinclassicalsubtypes.