PMID- 37131332
OWN - NLM
STAT- MEDLINE
DCOM- 20240123
LR  - 20240302
IS  - 1940-2465 (Electronic)
IS  - 1066-8969 (Print)
IS  - 1066-8969 (Linking)
VI  - 32
IP  - 1
DP  - 2024 Feb
TI  - Intra-Abdominal and Retroperitoneal Benign Lipomatous Tumors-An Extremely Rare 
      Mimic of Liposarcoma and its Diagnostic Challenge.
PG  - 46-57
LID - 10.1177/10668969231167511 [doi]
AB  - Background. Lipomas are common superficial soft tissue tumors of mature 
      adipocytes. In contrast, well-differentiated/dedifferentiated liposarcoma 
      typically presents in the retroperitoneum as large masses. We provide 
      clinicopathologic and follow-up details of 9 retroperitoneal/intra-abdominal 
      benign lipomatous tumors (BLT) and discuss the utility of ancillary fluorescence 
      in situ hybridization (FISH) in distinguishing from their malignant counterparts. 
      Design. Clinicopathologic details and histology of 9 intra-abdominal and 
      retroperitoneal lipomas were studied along with ancillary CD10 
      immunohistochemistry (IHC) and FISH for MDM2 and CDK4 amplification. Results. 
      There were 6 females and 3 males. Median age at diagnosis was 52 years (range 
      36-81 years). Seven were identified incidentally and 2 presented with primary 
      complaints. On imaging, 7 were considered suspicious for liposarcoma. Grossly, 
      the tumors ranged from 3.4 to 41.2 cm (median 16.5 cm). Histologically, all cases 
      showed well-differentiated BLT, further classified as lipoma (n = 7; 1 with 
      metaplastic ossification, 2 with prominent vessels, and 4 ordinary lipomas) and 
      lipoma-like hibernoma (n = 2)-the latter 2 showed intramuscular lesions with 
      interspersed brown fat. CD10 IHC showed strong staining in the 2 hibernomas, 
      whereas the staining was weak in the remaining. MDM2 and CDK4 amplification were 
      negative by FISH in all. Follow-up (median 18 months) did not show recurrence on 
      clinical or imaging evaluation. Conclusion. Retroperitoneal/intra-abdominal BLT 
      are extremely rare and are indistinguishable clinically and radiographically from 
      liposarcoma. This necessitates molecular confirmation even when the histology is 
      convincingly benign, for a confident diagnosis. Our cohort shows that 
      conservative excision without removal of abutted organs is sufficient in most 
      cases.
FAU - Malik, Faizan
AU  - Malik F
AUID- ORCID: 0000-0001-8597-5074
AD  - Department of Pathology and Laboratory Medicine, Perelman School of Medicine, 
      Hospital of the University of Pennsylvania, Philadelphia, PA, USA. RINGGOLD: 
      21798
FAU - Allbee, Andrew W
AU  - Allbee AW
AD  - Department of Pathology and Laboratory Medicine, Perelman School of Medicine, 
      Hospital of the University of Pennsylvania, Philadelphia, PA, USA. RINGGOLD: 
      21798
FAU - Zhang, Paul J
AU  - Zhang PJ
AD  - Department of Pathology and Laboratory Medicine, Perelman School of Medicine, 
      Hospital of the University of Pennsylvania, Philadelphia, PA, USA. RINGGOLD: 
      21798
LA  - eng
PT  - Journal Article
DEP - 20230502
PL  - United States
TA  - Int J Surg Pathol
JT  - International journal of surgical pathology
JID - 9314927
RN  - EC 2.3.2.27 (Proto-Oncogene Proteins c-mdm2)
RN  - EC 2.7.11.22 (Cyclin-Dependent Kinase 4)
RN  - 0 (Biomarkers, Tumor)
SB  - IM
MH  - Male
MH  - Female
MH  - Humans
MH  - Adult
MH  - Middle Aged
MH  - Aged
MH  - Aged, 80 and over
MH  - In Situ Hybridization, Fluorescence/methods
MH  - Proto-Oncogene Proteins c-mdm2/genetics
MH  - Cyclin-Dependent Kinase 4/genetics
MH  - Biomarkers, Tumor
MH  - *Liposarcoma/diagnosis/genetics
MH  - *Lipoma/diagnosis/genetics/pathology
PMC - PMC10901880
OTO - NOTNLM
OT  - CDK4
OT  - MDM2
OT  - lipoma
OT  - liposarcoma
OT  - retroperitoneum
COIS- Declaration of Conflicting InterestsThe author(s) declared no potential conflicts 
      of interest with respect to the research, authorship, and/or publication of this 
      article.
EDAT- 2023/05/03 06:42
MHDA- 2024/01/23 06:43
PMCR- 2024/02/29
CRDT- 2023/05/03 01:53
PHST- 2024/01/23 06:43 [medline]
PHST- 2023/05/03 06:42 [pubmed]
PHST- 2023/05/03 01:53 [entrez]
PHST- 2024/02/29 00:00 [pmc-release]
AID - 10.1177_10668969231167511 [pii]
AID - 10.1177/10668969231167511 [doi]
PST - ppublish
SO  - Int J Surg Pathol. 2024 Feb;32(1):46-57. doi: 10.1177/10668969231167511. Epub 
      2023 May 2.