Abstract：
Biphasic papillary renal cell carcinoma (synonymous with biphasic squamoid alveolar renal cell carcinoma) is considered within the spectrum of papillary renal cell carcinoma (PRCC). With < 70 reported cases of biphasic PRCC, there is limited data on the pathologic spectrum and clinical course. Seventeen biphasic PRCC cases and 10 papillary adenomas with similar biphasic morphology were assessed. The mean age of the biphasic PRCC patients was 62 years (male to female ratio of 1.8:1), from 10 partial nephrectomies, 6 radical nephrectomies, and 1 biopsy. The mean tumor size was 3.6 cm (range 1.6-8 cm), with 24% showing multifocality. Fifteen out of 17 cases were limited to the kidney (one of which was staged as pT2a but had lung metastases at diagnosis) and 2/17 cases were staged as T3a. All tumors showed typical biphasic morphology with an extent of squamoid foci widely variable from 10 to 95%. Emperipolesis was identified in 88% of cases. All biphasic PRCC tested exhibited positivity for PAX8 (16/16), keratin 7 (17/17), EMA (15/15), AMACR (17/17), and vimentin (12/12) in both large and small cells; cyclin D1 was only expressed in the large cells (16/16). The 10 papillary adenomas showed a similar immunoprofile to biphasic PRCC. NGS testing performed on 13 biphasic PRCC revealed 4 (31%) harboring MET SNVs. In 1/5 (20%) papillary adenomas, a pathogenic MET SNV was identified. Biphasic PRCC is rare with a generally similar immunoprofile to \"type 1\" PRCC but with notable strong positivity for cyclin D1 in the large cell component. Although most of the biphasic PRCC cases were of small size, low stage, and with an indolent behavior, one patient had metastatic disease and one patient died of the disease.
摘要：
双相乳头状肾细胞癌（双相鳞状肺泡细胞癌的同义词）被认为在乳头状肾细胞癌（PRCC）的范围内。报告的双相PRCC病例少于70例，关于病理谱和临床过程的数据有限。评估了17例双相PRCC病例和10例具有相似双相形态的乳头状腺瘤。双相PRCC患者的平均年龄为62岁（男女比例为1.8：1），从10例部分肾切除术中，根治性肾切除术6例,和1个活检。平均肿瘤大小为3.6cm（范围1.6-8cm），24%显示多焦点。17例中有15例仅限于肾脏（其中1例分期为pT2a，但诊断时有肺转移），2/17例分期为T3a。所有肿瘤均显示典型的双相形态，鳞状病灶的范围在10％至95％之间广泛变化。在88％的病例中发现了腹膜炎。所有双相PRCC测试显示PAX8阳性（16/16），角蛋白7（17/17），EMA（15/15），AMACR（17/17），和波形蛋白（12/12）在大细胞和小细胞中；细胞周期蛋白D1仅在大细胞中表达（16/16）。10个乳头状腺瘤显示出与双相PRCC相似的免疫特征。对13个双相PRCC进行的NGS测试显示，有4个（31％）携带METSNV。在1/5（20%）乳头状腺瘤中，确定了致病性METSNV。双相PRCC很少见，与“1型”PRCC具有相似的免疫特征，但在大细胞成分中对细胞周期蛋白D1具有明显的阳性。尽管大多数双相PRCC病例规模较小，低阶段，以一种懒惰的行为，1例患者患有转移性疾病,1例患者死于该疾病.
