Division of Cancer Medicine and Radiotherapy, The Norwegian Radium Hospital, Oslo University Hospital, Montebello, Oslo, Norway.
Acta Oncol. 2010;49(1):42-9. doi: 10.3109/02841860903081897.
Signet-ring cell carcinoma (SRCC) is an uncommon tumor entity in rectal cancer, often considered to be resistant to non-surgical therapy. In locally advanced primary or recurrent rectal cancer, diagnostic information from magnetic resonance imaging (MRI) is considered superior in planning the optimal treatment strategy, which usually includes preoperative radiotherapy. The recognition of MRI features that correlate with the radiation response might ultimately be used to select patients for tailored treatment and, in addition, avoid potentially toxic therapy in non-responding patients.
In a cohort of 120 rectal cancer patients who had received preoperative radiotherapy (50 Gy in 2 Gy fractions), six patients were noted to have SRCC tumor differentiation. Initial diagnostic MRI examination included assessment of local T- and N-stage and tumor morphology. Histological tumor response was subsequently assessed in the resected specimens, and postoperative follow-up data was compiled until disease recurrence.
Following the preoperative radiotherapy, two distinctly different histological responses - complete response (ypT0N0) or no response - were observed. Extensive mesorectal lymph node metastasis (N2 disease) at the pretreatment MRI examination was unambiguously associated with lack of response and rapid development of disseminated disease. Importantly, patients with complete response have been observed for 23-52 months postoperatively without evidence of recurrent disease.
Our review may suggest that patients with locally advanced growth of rectal SRCC, despite poorer outcome when compared to patients with conventional-type rectal adenocarcinoma, when presenting limited lymph node disease should be offered preoperative radiotherapy in a tentatively curative setting.
在直肠癌中，印戒细胞癌（SRCC）是一种罕见的肿瘤实体，通常被认为对非手术治疗具有抗性。在局部晚期原发性或复发性直肠癌中，磁共振成像（MRI）的诊断信息被认为在规划最佳治疗策略方面更具优势，该策略通常包括术前放疗。识别与辐射反应相关的 MRI 特征最终可能被用于选择接受针对性治疗的患者，并避免在无反应患者中使用潜在的毒性治疗。
在接受术前放疗（50 Gy 分 2 Gy 剂量）的 120 例直肠癌患者队列中，有 6 例患者被发现具有 SRCC 肿瘤分化。初始诊断性 MRI 检查包括局部 T 期和 N 期以及肿瘤形态的评估。随后在切除标本中评估组织学肿瘤反应，并收集术后随访数据直至疾病复发。
在术前放疗后，观察到两种截然不同的组织学反应 - 完全缓解（ypT0N0）或无反应。在预处理 MRI 检查中广泛的中直肠淋巴结转移（N2 疾病）与无反应和快速发展的弥散性疾病明确相关。重要的是，观察到完全缓解的患者在术后 23-52 个月内没有疾病复发的证据。
我们的回顾可能表明，尽管与常规型直肠腺癌患者相比，局部晚期生长的直肠 SRCC 患者的预后较差，但当出现有限的淋巴结疾病时，应在有希望治愈的情况下为其提供术前放疗。
