Collins Jennifer, Epstein Jonathan I
Department of Pathology, The Johns Hopkins Medical Institutions, Baltimore, MD 21231.
Department of Pathology, The Johns Hopkins Medical Institutions, Baltimore, MD 21231; Department of Urology, The Johns Hopkins Medical Institutions, Baltimore, MD 21231; Department of Oncology, The Johns Hopkins Medical Institutions, Baltimore, MD 21231.
Hum Pathol. 2017 Aug;66:108-114. doi: 10.1016/j.humpath.2017.06.010. Epub 2017 Jun 29.
Few studies using the current classification of renal cell carcinoma (RCC) have looked at a large number of cases with near total necrosis. We identified 21 cases of resections of RCC with >90% necrosis from the archives of Johns Hopkins Hospital between 2000 and 2015. Patients' mean age was 59 years (43-77) with 16 men (76%); 12 cases (57%) were papillary RCC, 4 clear cell papillary RCC (19%), 4 clear cell RCC (19%), and 1 unclassified with sarcomatoid differentiation (5%). International Society of Urological Pathology (ISUP) nucleolar grade was grade 1 (9 cases) or grade 2 (9 cases). Two cases were ISUP nucleolar grade 3, and 1 case was grade 4. Pathological stage was low (pT1-2) in 20 (95%) with the unclassified RCC with sarcomatoid differentiation RCC stage pT3a. Mean tumor size was 6.3 cm (1.2-17). In 52% (11) of cases, it was difficult to identify viable tumor, requiring multiple sections; 4 cases of papillary RCC were diagnosed in part due to necrotic tumor "ghost" architecture. Follow-up was available in 17 cases (81%) with a mean follow-up of 59 months. Thirteen patients (62%) are alive without disease. The patient with unclassified carcinoma with sarcomatoid differentiation died of cancer, and 2 died due to causes unrelated to cancer. One patient (5%) with low-grade clear cell RCC developed metastases but had a contralateral RCC. In the setting of a low-grade RCC, extensive necrosis does not have an adverse prognosis. In summary, our data, together with a prior study from our institution, comprise one of the largest cohorts of extensively (>90%) necrotic RCCs and suggests that in the setting of a low-grade RCC, it portends a good prognosis (only 2/36 cases showing progression (6%) on follow-up). However, we did identify a single case of high-grade RCC with an adverse prognosis and therefore, careful attention to tumor grade and classification is critical. The presence of tumor necrosis as a prognosticator in RCCs is complex, and despite its well-accepted role as an indicator of poor prognosis, our data would suggest otherwise under specific conditions. Importantly, in diagnosing a renal mass with extensive cystic necrosis, careful and extensive sampling to identify small foci of viable tumor or "ghost" architecture may be necessary for classification. As such, evaluation of its presence should not only be quantitative, but critical attention should be made to tumor grade and stage, whereby in high-grade carcinomas, necrosis likely imparts a worse prognosis; however, in low-grade carcinomas with extensive necrosis, the histological subtype, grade, and stage drive prognosis.
目前采用肾细胞癌（RCC）现有分类方法开展的研究中，很少有针对大量接近完全坏死病例的研究。我们从约翰霍普金斯医院2000年至2015年的档案中，识别出21例坏死率>90%的RCC切除术病例。患者的平均年龄为59岁（43 - 77岁），其中男性16例（76%）；12例（57%）为乳头状RCC，4例透明细胞乳头状RCC（19%），4例透明细胞RCC（19%），1例未分类伴肉瘤样分化（5%）。国际泌尿病理学会（ISUP）核仁分级为1级（9例）或2级（9例）。2例为ISUP核仁3级，1例为4级。病理分期低（pT1 - 2）的有20例（95%），未分类伴肉瘤样分化的RCC分期为pT3a。肿瘤平均大小为6.3 cm（1.2 - 17 cm）。52%（11例）的病例中，难以识别存活肿瘤，需要多张切片；4例乳头状RCC部分是由于坏死肿瘤的“鬼影”结构而确诊。17例（81%）有随访资料，平均随访时间为59个月。13例患者（62%）无病存活。未分类伴肉瘤样分化癌的患者死于癌症，2例死于与癌症无关的原因。1例（5%）低级别透明细胞RCC发生转移，但对侧有RCC。在低级别RCC情况下，广泛坏死并无不良预后。总之，我们的数据以及我们机构之前的一项研究，构成了最大的广泛（>90%）坏死RCC队列之一，表明在低级别RCC情况下，预示着良好的预后（随访中仅2/36例显示进展（6%））。然而，我们确实发现了1例预后不良的高级别RCC，因此，仔细关注肿瘤分级和分类至关重要。肿瘤坏死作为RCC的预后指标情况复杂，尽管其作为预后不良指标的作用已被广泛接受，但我们的数据表明在特定条件下并非如此。重要的是，在诊断伴有广泛囊性坏死的肾肿块时，可能需要仔细且广泛地取样以识别存活肿瘤的小病灶或“鬼影”结构用于分类。因此，对其存在的评估不仅应是定量的，还应密切关注肿瘤分级和分期，在高级别癌中，坏死可能预示更差的预后；然而，在伴有广泛坏死的低级别癌中，组织学亚型、分级和分期决定预后。
