Spleen
The spleen is a forgotten organ.
Normal histology
- Capsule.
- Red pulp - red blood cells.
- White pulp - white blood cells.
Splenic enlargement
- Portal hypertension (often due to cirrhosis).
- Lymphoma:
- Hairy cell leukemia.
- Splenic marginal zone lymphoma.[1]
- Splenic diffuse red pulp small B cell lymphoma.[2]
- Mononucleosis (EBV infection).
- Hemophagocytic syndrome.[3]
DDx by compartment
Red pulp benign
- Polycythemia rubra vera (AKA polycythemia vera).
- Outflow obstruction.
- Cirrhosis.
- Budd-Chiari syndrome (AKA hepatic vein obstruction).
- Splenic vein thrombosis.
- Congestive heart failure.
Red pulp malignant
- Hairy cell leukemia.
- Acute leukemia.[4]
- Hepatosplenic T-cell lymphoma[5] (AKA Hepatosplenic γδ T-cell lymphoma).
Specific disorders
Hyaloserositis
- Properly referred to as hyaloserositis of the spleen.
- Capsule of the spleen is white - resembles sugar-coating; also known as sugar-coated spleen.[6]
- Importance: none - benign.
Image(s):
Mononucleosis
General
- EBV infection.
- Massive splenic enlargement.
Microscopic
Features:
- Atypical lymphoid cells.
- Abundant basophilic cytoplasm.
- Cells indented by adjacent RBCs on blood smears.[7]
Image: Mononucleosis (med.utah.edu).[7]
Littoral cell angioma
- For angioma see vascular malformations.
- AKA littoral cell angioma of the spleen.
General
Features:[8]
- Rare.
- Benign.
- Pyrexia (fever), splenomegaly, weight loss, solitary hypodense lesion on imaging.
Note:
Microscopic
Features:[8]
- Anastoming, small vascular channels.
- Cystic spaces.
- May have papillary projections.[9]
DDx:[8]
- Vascular lesions:
Images:
- LCA - low mag. (webpathology.com).
- LCA - high mag. (webpathology.com).
- LCA - very low mag. (WC).
- LCA - intermed. mag. (WC).
- LCA - very high mag. (WC).
IHC
Features:[8]
- CD68 +ve.
- CD31 +ve
Splenic hamartoma
General
- Benign.
- Women > men.[12]
Microscopic
Features:[13]
- Variable size irregular vascular channels
- Red pulp-like disorganized stroma
- +/-Lymphoid follicles.
IHC
Features:[13]
- CD8 +ve endothelial cells.
Weird stuff
- Dendritic cell tumours.[4]
- Interdigitating dendritic cell tumour.
- Follicular dendritic cell tumour.
Follicular dendritic cell tumour
- AKA follicular dendritic cell sarcoma,[14] dendritic reticulum cell sarcoma, (???) follicular dendritic cell neoplasm. (???)
General
- Very rare.
- Behave like a low-grade sarcoma.[15]
- Reported association with Castleman disease (hyaline-vascular type).[15]
Microscopic
Features:[15]
- Oval or spindle-shaped cellular & nuclear morphology.
- Variable architecture (sheets, fascicles, whorles, storiform pattern).
- Nuclei:
- Small nucleoli.
- Clear or dispersed chromatin.
- Multinucleated cells.
- Interspersed small lymphocytes - distinctive feature.
- +/-Necrosis.
- +/-Marked nuclear atypia.
- +/-Abundant mitoses.
Images:
IHC
Features:[15]
- CD21 +ve.
- CD35 +ve.
- Ki-M4p +ve
- Ki-FDRC1p +ve.
- Vimentin +ve.
- S-100 +ve/-ve.
- Muscle-specific actin +ve/-ve.
- EMA +ve/-ve.
Hepatosplenic T-cell lymphoma
- AKA hepatosplenic γδ T-cell lymphoma.
- Abbreviated HSTL.
General
- Rare.
Clinical triad:
- Hepatosplenomegaly.
- Cytopenias (anemia, thrombocytopenia).
- Sinusoidal tropism.
Microscopic
Features:[5]
- Small cell lymphoma.
DDx:
IHC
Features:[5]
- CD4 -ve.
- CD8 -ve.
See also
References
- ↑ Bennett, M.; Schechter, GP. (Apr 2010). "Treatment of splenic marginal zone lymphoma: splenectomy versus rituximab.". Semin Hematol 47 (2): 143-7. doi:10.1053/j.seminhematol.2010.01.004. PMID 20350661.
- ↑ Baseggio L, Traverse-Glehen A, Callet-Bauchu E, et al. (March 2011). "Relevance of a scoring system including CD11c expression in the identification of splenic diffuse red pulp small B-cell lymphoma (SRPL)". Hematol Oncol 29 (1): 47–51. doi:10.1002/hon.957. PMID 20677173.
- ↑ Maakaroun, NR.; Moanna, A.; Jacob, JT.; Albrecht, H. (Mar 2010). "Viral infections associated with haemophagocytic syndrome.". Rev Med Virol 20 (2): 93-105. doi:10.1002/rmv.638. PMID 20127750.
- ↑ 4.0 4.1 Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 596. ISBN 978-0781765275.
- ↑ 5.0 5.1 5.2 Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 595. ISBN 978-0781765275.
- ↑ URL: http://www.drugs.com/dict/sugar-coated-spleen.html. Accessed on: 1 September 2010.
- ↑ 7.0 7.1 URL: http://library.med.utah.edu/WebPath/EXAM/IMGQUIZ/hpfrm.html. Accessed on: 4 December 2011.
- ↑ 8.0 8.1 8.2 8.3 8.4 8.5 Tan, YM.; Chuah, KL.; Wong, WK. (Jul 2004). "Littoral cell angioma of the spleen.". Ann Acad Med Singapore 33 (4): 524-6. PMID 15329769. http://www.annals.edu.sg/pdf200408/V33N4p524.pdf.
- ↑ 9.0 9.1 Dascalescu, CM.; Wendum, D.; Gorin, NC. (Sep 2001). "Littoral-cell angioma as a cause of splenomegaly.". N Engl J Med 345 (10): 772-3. doi:10.1056/NEJM200109063451016. PMID 11547761. http://www.nejm.org/doi/full/10.1056/NEJM200109063451016.
- ↑ URL: http://www.merriam-webster.com/dictionary/littoral. Accessed on: 24 July 2011.
- ↑ URL: http://dictionary.reference.com/browse/littoral. Accessed on: 24 July 2011.
- ↑ Sankar, S.; Thanka, J.; Jagdishchandrabose, S.; Rajendran, S.. "Splenic hamartoma: a rare vascular space occupying lesion of the spleen.". Indian J Pathol Microbiol 54 (1): 223-5. doi:10.4103/0377-4929.77416. PMID 21393931.
- ↑ 13.0 13.1 Lee, H.; Maeda, K. (Jan 2009). "Hamartoma of the spleen.". Arch Pathol Lab Med 133 (1): 147-51. doi:10.1043/1543-2165-133.1.147. PMID 19123729.
- ↑ 14.0 14.1 Leipsic, JA.; McAdams, HP.; Sporn, TA. (Jun 2007). "Follicular dendritic cell sarcoma of the mediastinum.". AJR Am J Roentgenol 188 (6): W554-6. doi:10.2214/AJR.04.1530. PMID 17515347.
- ↑ 15.0 15.1 15.2 15.3 Perez-Ordoñez, B.; Rosai, J. (May 1998). "Follicular dendritic cell tumor: review of the entity.". Semin Diagn Pathol 15 (2): 144-54. PMID 9606805.