INTRODUCTION Previous studies indicated that location and amount of detected sentinel lymph nodes (SLNs) in prostate cancer (PCa) are influenced where SLN-tracer is deposited within the prostate. To validate whether intratumoral (IT) tracer injection helps to increase identification of tumor-positive lymph nodes (LNs) better than intraprostatic (IP) tracer injection, a prospective randomized phase II trial was performed. METHODS PCa patients with a > 5% risk of lymphatic involvement were randomized between ultrasound-guided transrectal injection of indocyanine green-[99mTc]Tc-nanocolloid in 2 depots of 1 mL in the tumor (n = 55, IT-group) or in 4 depots of 0.5 mL in the peripheral zone of the prostate (n = 58, IP-group). Preoperative lymphoscintigraphy and SPECT/CT were used to define the location of the SLNs. SLNs were dissected using combination of radio- and fluorescence-guidance, followed by extended pelvic LN dissection and robot-assisted radical prostatectomy. Outcome measurements were number of tumor-bearing SNs, tumor-bearing LNs, removed nodes, number of patients with nodal metastases, and metastasis-free survival (MFS) of 4-7-year follow-up data. RESULTS IT-injection did not result in significant difference of removed SLNs (5.0 vs 6.0, p = 0.317) and histologically positive SLNs (28 vs 22, p = 0.571). However, in IT-group, the SLN-positive nodes were 73.7% of total positive nodes compared to 37.3% in IP-group (p = 0.015). Moreover, significantly more node-positive patients were found in IT-group (42% vs 24%, p = 0.045), which did not result in worse MFS. In two patients (3.6%) from whom the IT-tracer injection only partly covered intraprostatic tumor spread, nodal metastases in ePLND without tumor-positive SNs were yielded. CONCLUSIONS The percentage-positive SLNs found after IT-injection were significantly higher compared to IP-injection. Significantly more node-positive patients were found using IT-injection, which did not affect MFS. IT-injection failed to detect nodal metastases from non-index satellite lesions. Therefore, we suggest to combine IT- and IP-tracer injections in men with visible tumor on imaging.

中文翻译：

---

引流路径对前列腺癌淋巴结转移检测的影响：肿瘤内与前列腺内示踪剂注射用于前哨淋巴结检测的 II 期随机比较。

引言 以前的研究表明，前列腺癌 (PCa) 中检测到的前哨淋巴结 (SLN) 的位置和数量会受到 SLN 示踪剂在前列腺内沉积的影响。为了验证肿瘤内 (IT) 示踪剂注射是否比前列腺内 (IP) 示踪剂注射更有助于增加对肿瘤阳性淋巴结 (LN) 的识别，进行了一项前瞻性随机 II 期试验。方法 淋巴管受累风险 > 5% 的 PCa 患者随机接受超声引导下经直肠注射吲哚菁绿-[99mTc]Tc-纳米胶体的 2 个 1 mL 储库（n = 55，IT 组）或前列腺外周区 4 个 0.5 mL 贮库（n = 58，IP 组）。术前淋巴显像和 SPECT/CT 用于确定 SLN 的位置。使用放射和荧光引导相结合的方式解剖 SLN，然后进行扩展的盆腔 LN 解剖和机器人辅助的根治性前列腺切除术。结果测量是带肿瘤的 SN 的数量、带肿瘤的 LN 的数量、切除的淋巴结、淋巴结转移的患者数量和 4-7 年随访数据的无转移生存期 (MFS)。结果 IT 注射未导致去除的 SLN（5.0 对 6.0，p = 0.317）和组织学阳性 SLN（28 对 22，p = 0.571）的显着差异。然而，在 IT 组中，SLN 阳性淋巴结占阳性淋巴结总数的 73.7%，而 IP 组为 37.3%（p = 0.015）。此外，在 IT 组中发现明显更多的淋巴结阳性患者（42% vs 24%，p = 0.045），这并没有导致更差的 MFS。两名患者 (3. 6%）的 IT 示踪剂注射仅部分覆盖了前列腺内肿瘤扩散，在没有肿瘤阳性 SN 的 ePLND 中产生了淋巴结转移。结论与 IP 注射相比，IT 注射后发现的阳性 SLN 百分比显着更高。使用 IT 注射发现明显更多的淋巴结阳性患者，这不影响 MFS。IT 注射未能检测到非指标卫星病变的淋巴结转移。因此，我们建议将 IT 和 IP 示踪剂注射结合在影像学可见肿瘤的男性中。IT 注射未能检测到非指标卫星病变的淋巴结转移。因此，我们建议将 IT 和 IP 示踪剂注射结合在影像学可见肿瘤的男性中。IT 注射未能检测到非指标卫星病变的淋巴结转移。因此，我们建议将 IT 和 IP 示踪剂注射结合在影像学可见肿瘤的男性中。