FISH assay identifying oral cancer patients at low risk of lymph node metastasis

描述(申请人提供)：在美国，死于口腔鳞状细胞癌(SCC)的人比死于黑色素瘤、宫颈癌或卵巢癌的人多，而且发病率正在上升，特别是在年轻人中。颈部转移是死亡的主要原因；然而，并不是所有的口腔鳞状细胞癌都有转移。由于目前在原发癌手术切除前通过临床或放射检查发现转移的准确性较差，根据目前的风险评估能力，如果转移风险为&gt；20%，则进行颈淋巴清扫手术。因此，几乎所有口腔鳞状细胞癌患者都会接受颈淋巴清扫术，这会增加患者的发病率。我们实验室最近的研究区分了两种口腔鳞状细胞癌亚型，它们具有不同的分子特征和转移率。一种亚型，3q8pq20亚型，其特征是存在一种或多种复发性拷贝数异常，即+3q、-8p、+8q和/或+20。另一种亚型(非3q8pq20)缺乏这些拷贝数改变。非3q8pq20亚型的转移风险较低(7%)，而3q8pq20亚型的转移率为46%。这一观察结果在一项独立的口腔鳞癌队列中得到了重复。因此，这些基因中的一个或多个的DNA拷贝数改变是识别一组低转移风险患者的生物标志物，这些患者可以避免潜在的不必要的大手术切除颈部淋巴结。作为对PA-09-158的回应，我们建议开发我们的DNA拷贝数签名(+3q，-8p，+8q，+20)作为临床测试，以识别非3q8pq20亚群的低转移风险患者。为此，我们将开发并验证一种基于FISH的方法来检测染色体3q、8p、8q和20的DNA拷贝数，该方法适用于分析手术前收集的皮损刷检标本。工作的重点将是样本收集(目标1)和鱼类检测拷贝数(目标2)。我们寻求最适合临床应用的标本采集技术和分析技术的结合。经过验证和优化的分析将在随后的多机构前瞻性试验中用于评估3q8pq20状态，以确定该生物标记物用于识别不需要颈淋巴清扫的患者。 公共卫生相关性：颈部转移是口腔癌患者预后的主要决定因素。在这里，一种最近确定的低转移风险肿瘤的分子标记的检测方法将得到验证，并将发展为临床测试。该分析格式将适用于在手术前的患者评估期间收集的患者样本的分析，以使临床医生能够自信地识别那些颈部转移风险较低的患者，这些患者在手术切除肿瘤时，可以免除切除颈部淋巴结所需的额外大手术。

DESCRIPTION (provided by applicant): In the USA, more people die from oral squamous cell carcinoma (SCC) than melanoma, cervical or ovarian cancer and the incidence, particularly in young people, is increasing. Neck metastasis is the primary cause of death; however, not all oral SCCs metastasize. Due to the current poor accuracy in detecting metastasis by clinical or radiographic examination prior to surgical removal of the primary cancer, neck dissection, surgery to remove the cervical (neck) lymph nodes is performed if the metastatic risk is >20% based on current risk assessment capability. Therefore, almost all oral SCC patients undergo a neck dissection which increases patient morbidity. Recent studies in our laboratories have discriminated two oral SCC subtypes with distinct molecular signatures and metastatic rates. One subtype, the 3q8pq20 subtype, is characterized by the presence of one or more of the recurrent copy number aberrations, +3q, - 8p, +8q and/or +20. The other subtype (non-3q8pq20) lacks these copy number alterations. The non-3q8pq20 subtype is associated with a low risk of metastasis (7%) compared to the 46% rate of metastasis in the 3q8pq20 subtype. This observation has been replicated in an independent oral SCC cohort. Thus, DNA copy number alterations at one or more of these loci is a biomarker identifying a group of patients at low risk for metastasis, who could be spared the potentially unnecessary major surgery required for removal of the cervical lymph nodes. In response to PA-09-158, we are proposing to develop our DNA copy number signature (+3q, -8p, +8q, +20) as a clinical test to identify the non-3q8pq20 subset of patients at low risk for metastasis. To this end, we will develop and validate a FISH-based assay to detect DNA copy number for chromosomes 3q, 8p, 8q and 20 that is suitable for analysis of lesional brush biopsies collected prior to surgery. Work will focus on sample collection (Aim 1) and copy number detection by FISH (Aim 2). We seek the combination of specimen collection technique and analysis technology that would be best suited for clinical implementation. The validated and optimized assay will be used to assess 3q8pq20 status in a subsequent multi-institutional prospective trial to establish the utility of this biomarker to identify patients who do not require a neck dissection. PUBLIC HEALTH RELEVANCE: Neck metastasis is the primary determinant for prognosis of oral cancer patients. Here, an assay for a recently identified molecular signature for tumors with low risk of metastasis will be validated and developed into a clinical test. The assay format will be suitable for analysis of patient samples collected during the period of patient evaluation prior to surgery in order to allow clinicians to confidently identify those patients at low risk for neck metastasis, who, at the time of surgical removal of their tumors, could be spared the additional major surgery required to remove the neck lymph nodes.