PMID- 34463336
OWN - NLM
STAT- MEDLINE
DCOM- 20220203
LR  - 20220531
IS  - 1943-7722 (Electronic)
IS  - 0002-9173 (Linking)
VI  - 157
IP  - 1
DP  - 2022 Jan 6
TI  - Loss of Methylthioadenosine Phosphorylase by Immunohistochemistry Is Common in 
      Pulmonary Sarcomatoid Carcinoma and Sarcomatoid Mesothelioma.
PG  - 33-39
LID - 10.1093/ajcp/aqab091 [doi]
AB  - OBJECTIVES: Differentiating malignant pleural mesothelioma from benign reactive 
      mesothelial processes can be quite challenging. Ancillary tests such as 
      BRCA1-associated protein 1 (BAP1) immunohistochemistry and p16 fluorescence in 
      situ hybridization (FISH) are helpful tools to aid in this distinction. 
      Immunohistochemistry for methylthioadenosine phosphorylase (MTAP) has recently 
      been proposed as an effective surrogate marker for p16 FISH and is an attractive 
      alternative test due to shorter turnaround time. There are little data regarding 
      the specificity of MTAP loss for mesothelioma or whether it may be useful to 
      distinguish mesothelioma from the most common entity in the differential 
      diagnosis, sarcomatoid carcinoma. METHODS: We studied well-characterized cases of 
      sarcomatoid carcinoma (n = 34) and sarcomatoid mesothelioma (n = 62), which were 
      stained for MTAP (clone 2G4) and BAP1 (clone C-4). RESULTS: Loss of MTAP 
      expression was observed in 17 (50%) of 34 pulmonary sarcomatoid carcinomas; BAP1 
      expression was retained in all of the cases in which it was performed (n = 31). 
      MTAP expression was lost in 38 (61%) of 62 sarcomatoid mesotheliomas; BAP1 was 
      lost in 6 (10%) of 62. In the six cases with BAP1 loss, five also had loss of 
      MTAP, while MTAP expression was retained in one. CONCLUSIONS: Loss of MTAP 
      expression by immunohistochemistry is common in pulmonary sarcomatoid carcinoma, 
      as it is present in half of cases. This rate is similar to what is observed in 
      sarcomatoid mesothelioma (61%). Therefore, this stain is not useful to 
      distinguish between these two malignancies. MTAP loss is more common than BAP1 
      loss in the setting of sarcomatoid mesothelioma (61% vs 10%, respectively).
CI  - (c) American Society for Clinical Pathology, 2021. All rights reserved.For 
      permissions, please e-mail: journals.permissions@oup.com.
FAU - Terra, Simone
AU  - Terra S
AUID- ORCID: 0000-0001-7560-2346
AD  - Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Roden, Anja C
AU  - Roden AC
AD  - Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Yi, Eunhee S
AU  - Yi ES
AD  - Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Aubry, Marie Christine
AU  - Aubry MC
AD  - Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.
FAU - Boland, Jennifer M
AU  - Boland JM
AD  - Division of Anatomic Pathology, Mayo Clinic, Rochester, MN, USA.
LA  - eng
PT  - Journal Article
PL  - England
TA  - Am J Clin Pathol
JT  - American journal of clinical pathology
JID - 0370470
RN  - 0 (BAP1 protein, human)
RN  - 0 (Biomarkers, Tumor)
RN  - 0 (Tumor Suppressor Proteins)
RN  - EC 2.4.2.1 (Purine-Nucleoside Phosphorylase)
RN  - EC 2.4.2.28 (5'-methylthioadenosine phosphorylase)
RN  - EC 3.4.19.12 (Ubiquitin Thiolesterase)
SB  - IM
MH  - Biomarkers, Tumor
MH  - *Carcinoma/diagnosis
MH  - Diagnosis, Differential
MH  - Humans
MH  - Immunohistochemistry
MH  - In Situ Hybridization, Fluorescence
MH  - *Lung Neoplasms/diagnosis
MH  - *Mesothelioma, Malignant/diagnosis
MH  - Purine-Nucleoside Phosphorylase
MH  - Tumor Suppressor Proteins
MH  - Ubiquitin Thiolesterase
OTO - NOTNLM
OT  - BAP1
OT  - MTAP
OT  - Sarcomatoid carcinoma
OT  - Sarcomatoid mesothelioma
EDAT- 2021/09/01 06:00
MHDA- 2022/02/04 06:00
CRDT- 2021/08/31 09:03
PHST- 2021/02/19 00:00 [received]
PHST- 2021/04/26 00:00 [accepted]
PHST- 2021/09/01 06:00 [pubmed]
PHST- 2022/02/04 06:00 [medline]
PHST- 2021/08/31 09:03 [entrez]
AID - 6360386 [pii]
AID - 10.1093/ajcp/aqab091 [doi]
PST - ppublish
SO  - Am J Clin Pathol. 2022 Jan 6;157(1):33-39. doi: 10.1093/ajcp/aqab091.