2Lymphadenopathy (1)Lymphadenopathy is a common clinical finding with a broad differential diagnosis, and is frequently benign.In one series of 543 patients for further evaluation of lymphadenopathy,only 17.5% had an underlying malignant disorder (11.4% : lymphoproliferative disorder and 6.1% : metastatic solid tumor.The other had benign reactive lymphadenopathy and miscellaneous non-neoplastic diseases.Br J Cancer 2003;88:354–361
3Lymphadenopathy (2) Localized lymphadenopathy may suggest a local infectionsupraclavicular, axillary, or epitrochlear LNs have a greater probability of malignancyMetastatic solid tumorsGeneralized lymphadenopathyparticularly concerning for lymphoma or a systemic disease that mimics lymphoma
4Causes of Lymphadenopathy: CHICAGO CancersHypersensitivity syndromesInfectionsConnective tissue diseasesAtypical lymphoproliferative disordersGranulomatous disordersOther unusual causes of lymphadenopathy
5Cancers Hematologic malignancies: Hodgkin disease, non-Hodgkin lymphoma, acute and chronic leukemia, multiple myelomaMetastatic “solid” tumors:breast, lung, renal cell, prostate, other
15(according to excisional Bx of left neck LN) Lymphoma ?Lymphoid hyperplasia !(according to excisional Bx of left neck LN)
16Nodal FDG uptake is non-specific finding and could be seen in lymphoid hyperplasialymphadenitisbenign and atypical lymphoproliferative disordermalignancyRadiologic findings shown by the CT images of FDG PET/CT may be helpful.
17Radiologic sign (1) Signs suggestive of a benign etiology: measures < 1 cm in diameterhas a smooth, well defined bordershows homogeneous densityNormal reniform shape : C-shape thin & even cortex and intact central fatty hilum
19Radiologic sign (2) Signs suggestive of a malignant etiology: Nodal size > 2 cm (insensitive)Loss of the central fatty hilum or eccentric hilumEccentric cortical thickening/lobulationAbnormal lymph node shape: Round nodeCentral nodal necrosis: A central area of low “water” attenuationExtracapsular spread : Irregular nodal margin with infiltration around
33Lymphoma ? Sarcoidosis ! according to his clinical history: sarcoidosis diagnosed with F/U at VGH
34Sarcoidosis (1)An inflammatory multisystem granulomatous disease of unknown etiologyFormation of noncaseating epithelioid granulomas in tissues without another known cause for granulomatous disease.-- a diagnosis of exclusion.Diagnosis is established when the clinical and radiographic findings are supported by histologic evidence.
35Sarcoidosis (2)Most present with bilateral hilar lymphadenopathy, lung parenchymal disease, and eye or skin lesions.At diagnosis, 50% are asymptomatic, 25% complain of cough or dyspnea, 25% have eye symptoms or skin lesions.Can affect any organ :lung (90%), lymph node (75~90%), liver (60~90%), spleen (50~60%), joint (25~50%), bone marrow (15~40%), salivary gland (10%), heart (5%), nervous system (5%), and kidney (rare).
36Sarcoidosis (3)- Radiologic findings Typical finding:bilateral hilar and/or mediastinal LAPsAtypical finding:mediastinal LAPs unaccompanied by hilar LAP, isolated unilateral hilar LAPDytrophic calcification of involved LNs (related to duration of disease). -- amorphous, punctate, popcorn-like, eggshell.
39Lymphoma ? Kikuchi’s disease ! (Histiocytic necrotizing lymphadenitis) according to excisional Bx of neck LN
40Kikuchi’s disease (1) A self-limited, benign, reactive lymphadenitis Clinically, characterized most commonly byposterior cervical lymphadenopathyflu-like prodrome with fever (50%)resolve spontaneously within several weeks to monthsThe etiology of Kikuchi’s disease remains unclear
41Kikuchi’s disease (2)Diagnosis is confirmed only by excisional biopsy of lymph node.Histological findings,necrosis with nuclear debris (karyorrhexis)proliferation of histiocytes with crescentic nuclei.Treatment is generally conservative. Steroids may be used for severe symptoms.
42Kikuchi’s disease (3) Lymphadenopathy of Kikuchi’s disease: One location in 83% of patients, although multiple nodal chains may be occasionally involvedCervical nodes are affected in 80% of patients (60~70% involve posterior triangle cervical nodes)Less commonly affected nodes : axillary, mediastinal, celiac, abdominal, inguinal location.The nodes tend to be 2~3 cm in diameter, although larger lymph nodes may be seen
61Infectious mononucleosis ! Lymphoma ?Infectious mononucleosis !(according to clinical diagnosis and follow up at other hospital)
62Infectious mononucleosis (1) Most common cause : Epstein-Barr virus infection.Most patients are asymptomatic. Non-specific symptoms include fatigue, malaise, fever, sorethroat, nausea and anorexia.Early signs: fever, lymphadenopathy, pharyngitis, rash, and/or periorbital edema.Late signs: hepatomegaly, splenomegaly, palatal petechiae.Presence of typical syndrome and positive result on a heterophilic antibody test (Monospot test) confirm the diagnosis.
63Infectious mononucleosis (2) Lymphadenopathy in infectious mononucleosis:Any or all chains may be enlarged, bilateral posterior cervical adenopathy is most commonAlways bilateral and symmetricalSplenomegaly is usually accompanied by lymphadenopathyGeneralized adenopathy with prominent splenomegaly should include EBV infectious mononucleosis in the differential diagnosis.
64Hypermetabolic adenopathy seen frequently in the FDG PET images – Imaging mimics of lymphoma In the case of more generalized lymphadenopathy, in addition to the more common lymphomas, benign etiologies & benign and atypical lymphoproliferative disorders need to be considered.Diagnosis only on basis of PET findings is almost impossible. Clinical, laboratory, radiologic and histopathologic findings should be included for final diagnosis.