Contemporary Incidence and Predictors of Occult Inguinal Lymph Node Metastases in Men With Clinically Node-negative (cN0) Penile Cancer

Efficacy of indocyanine green fluorescence-guided inguinal lymph node dissection for penile cancer: a randomised trial

OBJECTIVES

To investigate the safety and efficacy of indocyanine green (ICG) fluorescence-guided inguinal lymph node dissection (ILND) in patients with penile cancer.

PATIENTS AND METHODS

A prospective, single-blind, randomised controlled clinical trial (ChiCTR2100044584) was performed among patients with penile caner who underwent bilateral modified ILND at four centres in China between 1 April 2021 and 30 June 2022. Patients aged 18-80 years and diagnosed with squamous cell carcinomas were included. Each enrolled patient was randomly assigned to either ICG fluorescence-guided ILND by a laparoscopic or robot-assisted approach in one groin, with non-ICG fluorescence-guided ILND in the other groin acting as a control. The primary outcome was the number of retrieved ILNs. Secondary outcomes included complications according to the Clavien-Dindo classification and the ILN non-compliance (inadequate removal of ILNs) rate.

RESULTS

A total of 45 patients were included in the intention-to-treat (ITT) analysis, and the 42 who completed the entire study were included in the per protocol (PP) analysis. There were no ICG-related complications in any of the patients. The results of the ITT and PP analyses indicated that the total number of unilateral ILNs retrieved was higher on the ICG side than on the non-ICG side (mean 13 vs 9 ILNs, difference 4 ILNs [95% CI 2.7-4.4], P = 0.007), and the number of unilateral deep and superficial ILNs was higher on the ICG side. Furthermore, the LN non-compliance rate was lower on the ICG side than on the non-ICG side. Additionally, there was no significant difference in local complications in the groins between the two sides (P > 0.05).

CONCLUSION

An ICG fluorescence-guided ILND was safe for patients with penile cancer. This procedure can improve the number of ILNs retrieved and reduce the LN non-compliance rate without increased complications. ICG fluorescence-guided ILND is beneficial and recommended for selected patients with penile cancer.

Management of Lymph Node-positive Penile Cancer: A Systematic Review

CONTEXT

Lymph node (LN) involvement in penile cancer is associated with poor survival. Early diagnosis and management significantly impact survival, with multimodal treatment approaches often considered in advanced disease.

OBJECTIVE

To assess the clinical effectiveness of treatment options available for the management of inguinal and pelvic lymphadenopathy in men with penile cancer.

EVIDENCE ACQUISITION

EMBASE, MEDLINE, the Cochrane Database of Systematic Reviews, and other databases were searched from 1990 to July 2022. Randomised controlled trials (RCTs), nonrandomised comparative studies (NRCSs), and case series (CSs) were included.

EVIDENCE SYNTHESIS

We identified 107 studies, involving 9582 patients from two RCTs, 28 NRCSs, and 77 CSs. The quality of evidence is considered poor. Surgery is the mainstay of LN disease management, with early inguinal LN dissection (ILND) associated with better outcomes. Videoendoscopic ILND may offer comparable survival outcomes to open ILND with lower wound-related morbidity. Ipsilateral pelvic LN dissection (PLND) in N2-3 cases improves overall survival in comparison to no pelvic surgery. Neoadjuvant chemotherapy in N2-3 disease showed a pathological complete response rate of 13% and an objective response rate of 51%. Adjuvant radiotherapy may benefit pN2-3 but not pN1 disease. Adjuvant chemoradiotherapy may provide a small survival benefit in N3 disease. Adjuvant radiotherapy and chemotherapy improve outcomes after PLND for pelvic LN metastases.

CONCLUSIONS

Early LND improves survival in nodal disease in penile cancer. Multimodal treatments may provide additional benefit in pN2-3 cases; however, data are limited. Therefore, individualised management of patients with nodal disease should be discussed in a multidisciplinary team setting.

PATIENT SUMMARY

Spread of penile cancer to the lymph nodes is best managed with surgery, which improves survival and has curative potential. Supplementary treatment, including the use of chemotherapy and/or radiotherapy, may further improve survival in advanced disease. Patients with penile cancer with lymph node involvement should be treated by a multidisciplinary team.

Recent developments in the diagnosis and management of N1 penile cancer

PURPOSE OF REVIEW

This article presents a critical review of the current literature to provide a brief update on the contemporary advances in diagnosing and managing N1 penile cancer.

RECENT FINDINGS

Penile squamous cell carcinoma (pSCC) has evolved from being an orphan field for cancer innovation. Advances in the understanding tumour biology have enabled sophisticated diagnostics and predictive modelling to better characterize inguinal disease. Minimally invasive inguinal lymph node dissection is emerging as a technique that reduces morbidity while maintaining oncological safety. Furthermore, robust clinical trials are underway ,which will provide level one evidence to guide treatment decisions. Exciting advances in the field of immune-oncology offer promise as adjuvant therapies. International collaboration and centralisation of care will be essential to driving translational research and equitable evidence-based care.

SUMMARY

Improving outcomes for men with pSCC remains a global challenge. Radical inguinal lymph node dissection remains the gold standard for diagnosing and curing N1 disease. Although many promising developments are on the horizon, high-level evidence is required to guide therapy.

Prognostic predictors of lymph node metastasis in penile cancer: a systematic review

PURPOSE

Squamous cell carcinoma (SCC) of the penis is a rare disease in developed countries but is associated with significant morbidity and mortality. A crucial prognostic factor is the presence of inguinal lymph node metastases (ILNM) at the time of diagnosis. At least 25% of cases have micrometastases at the time of diagnosis. Therefore, we performed a literature review of studies evaluating factors, both clinical and pathological, predictive of lymph node metastases in penile SCC.

MATERIALS AND METHODS

Studies were identified using PubMed and search terms included the following: penile cancer, penile tumor, penile neoplasm, penile squamous cell carcinoma, inguinal lymph node metastasis, lymph node metastases, nodal metastasis, inguinal node metastasis, inguinal lymph node involvement, predictors, and predictive factor. The number of patients and predictive factors were identified for each study based on OR, HR, or RR in multivariate analyses, as well as their respective significance values. These were compiled to generate a single body of evidence supportive of factors predictive of ILNM in penile SCC.

RESULTS

We identified 31 studies, both original articles and meta-analyses, which identified factors predictive of metastases in penile SCC. The following clinical factors were predictive of ILNM in penile SCC: lymphovascular invasion (LVI), increased grade, increased stage (both clinical and pathological), infiltrative and reticular invasion, increased depth of invasion, perineural invasion, and younger patient age at diagnosis. Biochemically, overexpression of p53, SOD2, Ki-67, and ID1 were associated with spread of SCC to inguinal lymph nodes. Diffuse PD-L1 expression, increased SCC-Ag expression, increased NLR, and CRP >20 were also associated with increased ILNM.

CONCLUSIONS

A multitude of factors are associated with metastasis of SCC of the penis to inguinal lymph nodes, which is associated with poor clinical outcomes. The above factors, most strongly LVI, grade, and node positivity, may be considered when constructing a nomogram to risk-stratify patients and determine eligibility for prophylactic inguinal lymphadenectomy.