El Hag Mohamed, Schmidt Lindsay, Roh Michael, Michael Claire W
Department of Laboratory Medicine and Pathology, University of Minnesota Medical Center, 420 Delaware St SE, Minneapolis, Minnesota.
Department of Pathology, Marshfield Clinic, 3401 Cranberry Blvd, Weston, Wisconsin.
Diagn Cytopathol. 2016 Apr;44(4):299-304. doi: 10.1002/dc.23442. Epub 2016 Jan 22.
Similar to TTF-1, Napsin-A is recently used increasingly to differentiate between pulmonary adenocarcinoma (P-ADC) and extra-pulmonary adenocarcinoma (EP-ADC). The aim of this study was to compare the performance of TTF-1 and Napsin-A in determining the primary origin of adenocarcinoma in malignant serous effusion.
Following IRB approval, cellblocks from 139 cases of malignant serous effusions of histologically or clinically determined origin including: 26 P-ADC, 108 EP-ADC, 2 pulmonary squamous cell carcinoma (P-SQC), and 3 pulmonary small cell carcinoma (P-SCC) were retrieved. Each case was stained with Napsin-A and TTF-1 and evaluated for positivity and intensity of staining.
Napsin-A and TTF-1 stained positive in 17/26 (65%) and 14/26 (54%) of P-ADC and in 2/108 (1.8%) and 0/108 (0%) of EP-ADC with a PPV of 89 and 100%, respectively. In combination, they positively stained 18/26 (70%) of P-ADC with a PPV of 90%. Out of 9 poorly differentiated P-ADC, 7 (78%) stained positive for Napsin-A, while 4 (45%) were reactive for TTF-1. Both Napsin-A and TTF-1 were negative in P-SQC, while P-SCC reacted positively for TTF-1 in 2/3 (66%) of cases and none for Napsin-A.
Napsin-A and TTF-1 are both useful markers in distinguishing P-ADC from EP-ADC. However, Napsin-A performed better in poorly differentiated P-ADC and its mimickers. The nuclear staining of TTF-1 is crispier and much easier to interpret than Napsin-A cytoplasmic stain. An antibody panel including TTF-1 and Napsin-A or a dual stain will be very helpful in determining the origin of metastatic adenocarcinoma in serous effusion.
与甲状腺转录因子-1（TTF-1）类似，最近天冬氨酸蛋白酶A（Napsin-A）越来越多地用于鉴别肺腺癌（P-ADC）和肺外腺癌（EP-ADC）。本研究的目的是比较TTF-1和Napsin-A在确定恶性浆液性胸腔积液中腺癌原发灶方面的性能。
经机构审查委员会（IRB）批准，检索139例组织学或临床确定来源的恶性浆液性胸腔积液的细胞块，包括：26例P-ADC、108例EP-ADC、2例肺鳞状细胞癌（P-SQC）和3例肺小细胞癌（P-SCC）。对每个病例进行Napsin-A和TTF-1染色，并评估染色的阳性率和强度。
Napsin-A和TTF-1在26例P-ADC中的阳性率分别为17/26（65%）和14/26（54%），在108例EP-ADC中的阳性率分别为2/108（1.8%）和0/108（0%），阳性预测值分别为89%和100%。联合使用时，它们在26例P-ADC中的阳性率为18/26（70%），阳性预测值为90%。在9例低分化P-ADC中，7例（78%）Napsin-A染色阳性，4例（45%）TTF-1反应阳性。Napsin-A和TTF-1在P-SQC中均为阴性，而P-SCC在2/3（66%）的病例中TTF-1反应阳性，Napsin-A均为阴性。
Napsin-A和TTF-1都是区分P-ADC和EP-ADC的有用标志物。然而，Napsin-A在低分化P-ADC及其相似病变中表现更好。TTF-1的细胞核染色比Napsin-A的细胞质染色更清晰，更容易解读。包括TTF-1和Napsin-A的抗体组合或双重染色在确定浆液性胸腔积液中转移性腺癌的来源方面将非常有帮助。
