A risk calculator predicting recurrence in lymph node metastatic penile cancer

“Light green up”: Indocyanine Green Fluorescence Imaging–guided Robotic Bilateral Inguinal Lymphadenectomy by the Hypogastric Subcutaneous Approach for Penile Cancer

Background

Inguinal lymphadenectomy is of great significance in the management of penile cancer, which aims to mitigate the progression of lymph node metastasis. It is important to improve the efficiency of lymph node dissection and reduce surgical complications.

Objective

To detail a novel technique for robotic bilateral inguinal lymphadenectomy through the hypogastric subcutaneous approach by indocyanine green (ICG) fluorescence imaging, which promotes the identification and dissection of inguinal lymph nodes with considerable safety.

Design, setting, and participants

Ten eligible penile cancer patients who underwent ICG fluorescence imaging–guided robotic bilateral inguinal lymphadenectomy were prospectively enrolled (ICG group). Sixteen patients who underwent the surgery without ICG were retrospectively set as the control (non-ICG) group. Follow-up records for at least 12 mo were required.

Surgical procedure

Inguinal lymphadenectomy was performed by the hypogastric subcutaneous approach. The ICG solution was subcutaneously injected into the prepuce at the beginning of surgery, and ICG fluorescence imaging–guided robotic-assisted bilateral inguinal lymphadenectomy was conducted.

Measurements

Clinical outcomes were collected. The primary study outcome measurement was the number of dissected inguinal lymph nodes.

Results and limitations

The numbers of inguinal overall, superficial, and deep lymph nodes retrieved were all higher in the ICG than in the non-ICG group (p < 0.05). No patients had severe perioperative complications. No difference was found in the overall complication rate and 12-mo survival between two groups (p > 0.05).

Conclusions

ICG fluorescence imaging–guided robotic inguinal lymphadenectomy via the hypogastric subcutaneous approach is feasible and safe for patients with penile cancer, which is beneficial for dissecting more inguinal lymph nodes with few surgical complications.

Patient summary

We developed a promising indocyanine green fluorescence imaging–guided technique to perform robotic bilateral inguinal lymphadenectomy on patients with penile cancer, which conduces to remove more inguinal lymph nodes with limited complications.

A global approach to improving penile cancer care

Rare tumours such as penile carcinoma have been largely neglected by the urology scientific community in favour of more common - and, therefore, more easily fundable - diseases. Nevertheless, penile cancer represents a rising burden for health-care systems around the world, because a lack of widespread expertise, ineffective centralization of care and absence of research funds have hampered our ability to improve the global care of these patients. Moreover, a dichotomy has arisen in the field of penile cancer, further impeding care: the countries that are mainly supporting research on this topic through the development of epidemiological studies and design of clinical trials are not the countries that have the highest prevalence of the disease. This situation means that randomized controlled trials in developed countries often do not meet the minimum accrual and are intended to close before reaching their end points, whereas trials are almost completely absent in those areas with the highest disease prevalence and probability of successful recruitment, such as Africa, South America and South Asia. The scientific and organizational inaction that arises owing to this mismatch translates into a burdensome cost for our patients. A global effort to gather experts and pull together scientific data from around the world may be the best way to boost clinical research, to change clinical practice and, ultimately, to improve care for patients and their families.

Use of flaps in inguinal lymphadenectomy in metastatic penile cancer

PURPOSE

Reviewing surgical procedures using fasciocutaneous and myocutaneous flaps for inguinal reconstruction after lymphadenectomy in metastatic penile cancer.

MATERIAL AND METHODS

We reviewed the current literature of the Pubmed database according to PRISMA guidelines. The search terms used were "advanced penile cancer", "groin reconstruction", and "inguinal reconstruction", both alone and in combination. The bibliographic references used in the selected articles were also analyzed to include recent articles into our research.

RESULTS

A total of 54 studies were included in this review. About one third of penile cancers are diagnosed with locally advanced disease, often presenting with large lymph node involvement. Defects in the inguinal region resulting from the treatment of metastatic penile cancer are challenging for the surgeon and cause high patient morbidity, rendering primary closure unfeasible. Several fasciocutaneous and myocutaneous flaps of the abdomen and thigh can be used for the reconstruction of the inguinal region, transferring tissue to the affected area, and enabling tensionless closure.

CONCLUSIONS

The reconstruction of defects in the inguinal region with the aid of flaps allows for faster postoperative recovery and reduces the risk of complications. Thus, the patient will be able to undergo potential necessary adjuvant treatments sooner.

Lymph Node Dissections for T3T4 Stage Penile Cancer Patients Without Preoperatively Detectable Lymph Node Metastasis Bring More Survival Benefits: A Propensity Matching Analysis

Background and Aims

The current guidelines for the treatment of penile cancer patients with clinically non-invasive normal inguinal lymph nodes are still broad, so the purpose of this study is to determine which patients are suitable for lymph node dissection (LND).

Methods

Histologically confirmed penile cancer patients (primary site labeled as C60.9-Penis) from 2004 to 2016 in the Surveillance, Epidemiology, and Results database were included in this analysis. Univariate and multivariate Cox regression analyses were applied to determine an overall estimate of LND on overall survival and cancer-specific survival. A 1:1 propensity matching analysis (PSM) was applied to enroll balanced baseline cohort, and further Kaplan-Meier (KM) survival analysis was used to get more reliable results.

Results

Out of 4,458 histologically confirmed penile cancer patients with complete follow-up information, 1,052 patients were finally enrolled in this analysis. Age, pathological grade, T stage, and LND were identified as significant predictors for overall survival (OS) in the univariate Cox analysis. In the multivariate Cox regression, age, pathological grade, T stage, and LND were found significant. The same results were also found in the univariate and multivariate Cox regression analyses for cancer-specific survival (CSS). After the successful PSM, further KM analysis revealed that LND could bring significant OS and CSS benefits for T3T4 patients without lymph node metastasis.

Conclusion

Lymph node dissection may bring survival benefits for penile cancer patients without preoperatively detectable lymph node metastasis, especially for T3T4 stage patients. Further randomized control trial is needed.

Risk factors and survival outcomes for upstaging after inguinal lymph node dissection for cN1 penile squamous cell carcinoma

OBJECTIVES

To identify incidence and risk factors for upstaging from cN1 to pN2/N3 at inguinal lymphadenectomy (ILND) for penile cancer (pSCC). Our secondary objective is to assess survival outcomes and associations for cN1 patients undergoing ILND.

SUBJECTS/PATIENTS AND METHODS

Patients with pT≥1cN1cM0 pSCC who underwent bilateral ILND and had complete data were identified in a multi-institutional international cohort from 8 referral centers in 7 countries diagnosed from 1980 to 2017. Upstaging was defined as pN2/N3 at ILND. Multivariable logistic regression analysis was used to determine associations with upstaging, and Cox multivariable logistic regression analysis to determine associations with overall survival (OS).

RESULTS

Of 144 patients were included in the final study population. 84 patients (58%) were upstaged from cN1 to pN2/N3, and 25 (17%) were down staged to pN0. Upstaging was associated with pT3/T4 (OR 4.1, 95%CI 1.5-11.7, P < 0.01) and pTX (OR 7.1, 95CI 1.6-51.1, P = 0.02). Age, smoking status, HPV status, and LVI were not associated with upstaging. Age (HR 1.03/y, 95%CI 1.01-1.06, P < 0.01) and upstaging (HR 2.8, 95%CI 1.3-5.9, P < 0.01) were associated with worse OS. Upstaged patients had a 5-year OS of 49%, compared with 86% for patients who were not upstaged.

CONCLUSION

The majority of cN1 pSCC patients harbor a higher-risk disease state than their clinical staging suggests, especially those with higher pT stages. More intensive pre-operative workup may be warranted for these patients to identify upstaging prior to ILND and potentially qualify them for neoadjuvant chemotherapy or clinical trials.

Impact of Examined Lymph Node Count and Lymph Node Density on Overall Survival of Penile Cancer

BACKGROUND

Few studies have explored the optimal examined lymph node count and lymph node density cutoff values that could be used to predict the survival of patients with penile cancer. We further clarify the prognostic value of lymph node density and examined lymph node count in penile cancer.

METHODS

The Surveillance, Epidemiology, and End Results (SEER) database was explored to recruit penile cancer patients from 2010 to 2015. A retrospective analysis of penile cancer patients' data from the First Affiliated Hospital of Anhui Medical University was performed for verification (2006-2016). The cutoff values of examined lymph node count and lymph node density were performed according to the ROC curve. Kaplan-Meier survival analysis was used to compare survival differences among different groups. Univariate and multivariate Cox proportional hazard regression analyses were used to determine the significant variables. On the basis of Cox proportional hazards regression model, a nomogram was established and validated by calibration plot diagrams and concordance index (C-index).

RESULTS

A total of 528 patients in the Surveillance, Epidemiology, and End Results cohort and 156 patients in the Chinese cohort were included in this study. Using the ROC curve, we found that the recommended cutoff values of ELN and LND were 13 and 9.3%, respectively (P <0.001). Kaplan-Meier curves suggested the significant differences of overall survival among different examined lymph nodes and lymph node density. Multivariate analysis indicated ELN and LND were independent prognostic factor for OS of penile cancer patients. Nomogram showed the contribution of ELN and LND to predicting OS was large. The C-index at 3-, and 5-year were 0.744 for overall survival (95% CI 0.711-0.777).

CONCLUSIONS

The more lymph nodes examined, the lower the density of lymph nodes, and the higher the long-term survival rate of penile cancer. We recommended 13 examined lymph nodes and lymph node density >9.3% as the cutoff value for evaluating the prognosis of penile cancer patients.

Correlation Between the Evolution of Somatic Alterations During Lymphatic Metastasis and Clinical Outcome in Penile Squamous Cell Carcinoma

Penile squamous cell carcinoma (PSCC) is a rare malignancy with poor survival after standard treatment. Although genomic alterations of PSCC have been characterized in several latest studies, the association between the formation of somatic landscape and regional lymph node metastasis (LNM), an important predictor for patient survival, has not been comprehensively investigated. Here, we collected formalin-fixed paraffin-embedded tumor tissue and matched normal samples of 32 PSCC patients, including 14 LNM patients and 18 clinically node-negative patients, to implement a whole-exome sequencing. Comparison of genomic features among different lymph node status subgroups was conducted after genomic profiling and its effects on patient survival were explored. Top-ranked recurrent gene mutants in our PSCC cohort were TP53 (13/32), NOTCH1 (12/32), CDKN2A (11/32), TTN (9/32) and FAT1 (8/32), mainly identified in the Notch, Hippo, cell cycle, TP53, RTK-RAS and PI3K pathways. While CDKN2A was confirmed to be the driver gene in all PSCC patients, certain gene mutants were significantly enriched in LNM involved patients, including TP53 (9/14 vs. 4/18, p = 0.029) and GBF1 (4/14 vs. 0/18, p = 0.028). Overall survival stratification of PSCC patients were found to be significantly correlated with mutations of three genes, including PIK3CA (Hazard ratio [HR] = 4.15, p = 0.029), CHD7 (HR = 4.82, p = 0.032) and LAMC3 (HR = 15.9, p < 0.001). PIK3CA and LAMC3 held a higher prevalence in patients with LNM compared to those without LNM (PIK3CA: 3/14 vs. 1/18, LAMC3: 2/14 vs. 1/18). Our finding demonstrated that genomic divergence exists across PSCC patients with different lymph node statuses, and it may be correlated with their survival outcome. It helps delineate somatic evolution during tumor progression and perfect potential therapeutic intervention in this disease.

Association Between Human Papillomavirus Infection and Outcome of Perioperative Nodal Radiotherapy for Penile Carcinoma

BACKGROUND

Data on the impact of human papillomavirus (HPV) infection status and outcomes for perioperative treatments for patients with lymph node-involved penile squamous-cell carcinoma (PSCC) are lacking.

OBJECTIVE

To analyze the benefit from perioperative radiotherapy (RT) for PSCC according to HPV infection status.

DESIGN, SETTING, AND PARTICIPANTS

In an international multicenter database of 1254 patients with PSCC who received inguinal lymph node dissection (ILND), 507 had suitable clinical information.

INTERVENTION

ILND, with or without chemotherapy or RT for involved lymph nodes.

OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS

Kaplan-Meier and restricted mean survival time (RMST) analyses for overall survival (OS) were performed for all patients and after propensity score-matching (PSM; n = 136), for which patient age, histology, type of penile surgical procedure, pathological tumor and nodal stage, ILND laterality, pelvic LND, and perioperative treatment were taken into account when assessing differences between HPV⁺ and HPV- patients. Finally, we looked at genomic alterations in PSCC using data from the Foundation Medicine database (n = 199) to characterize HPV⁺ PSCC.

RESULTS AND LIMITATIONS

Patients with HPV⁺ PSCC (n = 86; 17%) had lower clinical N stage (p < 0.001) and inguinal lymph node metastasis density (p < 0.001). Perioperative RT was delivered in 49 patients (9.7%), with the vast majority receiving adjuvant RT (n = 40). HPV⁺ patients had similar median OS (p = 0.1) but longer RMST than HPV- patients at different time points. Nevertheless, HPV⁺ patients treated with perioperative RT exhibited longer median OS (p = 0.015) and longer RMST compared to HPV- patients. In the PSM cohorts, HPV⁺ status remained significantly associated with longer OS after RT. The HPV- PSCC group had a higher frequency of TP53 mutations compared to HPV⁺ PSCC (75% vs 15%; p < 0.001). The results are limited by the retrospective nature of the data.

CONCLUSIONS

Perioperative RT was more effective in the HPV⁺ PSCC subgroup. Reasons for the enhanced radiosensitivity may be related to the lack of TP53 mutations.

PATIENT SUMMARY

We analyzed data from a large multicenter database for patients with penile cancer who had received inguinal lymph node dissection, with or without chemotherapy or radiotherapy. We found that for tumors positive for human papillomavirus (HPV), use of radiotherapy resulted in prolonged survival compared to HPV-negative tumors. On the basis of these results we are inspired to design studies on the use of radiotherapy in HPV-selected patients.

Current management and future perspectives of penile cancer: An updated review

Penile cancer (PeCa) is a rare disease worldwide, accounting for less than one percent of all malignancies in men. It usually presents as a painless ulcer or lump on the head of the penis. Squamous cell carcinoma represents the most common histological subtype of PeCa, with pathogenesis intimately linked to chronic Human Papilloma Virus (HPV) infection. Surgery is the cornerstone for the treatment of primary PeCa with potential mutilating outcome depending on the nodal extension of the disease. However, in case of extensive lymph node involvement, multidisciplinary treatment including perioperative chemotherapy and inclusion in clinical trial should be considered. To date, advanced or metastatic disease still have poor prognosis and are a therapeutic challenge with limited options, highlighting the need of new treatments and further investigations. Growing efforts to identify molecular alterations, understand the role of HPV and characterize immune contexture have expanded over the past years, providing further perspectives in prognostication, predictive biomarkers and therapeutic intervention. In this review, we provide an updated overview of current management of PeCa focusing on perioperative strategy. We discuss about new insights of the biology of PeCa and comment future directions in the field.