Detection of lymph node metastases in penile cancer

Current Role of PET CT in Staging and Management of Penile Cancers

Penile cancer (PeCa) is a rare urological malignancy characterized by significant geographical variations in both incidence and mortality rates. Due to its rarity and the consequent lack of randomized trials, current management is based on retrospective studies and small prospective trials. In addition, both the diagnostic pathways and treatment strategies exhibit substantial heterogeneity, differing significantly between less-developed and well-developed countries. The prognosis of PeCas is determined by the presence and extent of regional lymph node (LN) involvement. Therefore, the early detection and treatment of LN metastasis is paramount to ensure better outcomes. In recent decades, overall survival of PeCas has increased, mainly due to advancements in imaging techniques and risk stratification. We aim to provide an overview of the current role of PET CT imaging in the management of patients with PeCa.

Exploring the Multifactorial Landscape of Penile Cancer: A Comprehensive Analysis of Risk Factors

Penile cancer, while rare, is a critical public health issue due to its profound impact on patients and the complexities of its management. The disease's multifactorial etiology includes risk factors such as HPV infection, poor hygiene, smoking, genetic predispositions, and socioeconomic determinants. This article provides a comprehensive review and analysis of these diverse risk factors, aiming to enhance understanding of the disease's underlying causes. By elucidating these factors, the article seeks to inform and improve prevention strategies, early detection methods, and therapeutic interventions. A nuanced grasp of the multifactorial nature of penile cancer can enable healthcare professionals to develop more effective approaches to reducing incidence rates and improving patient outcomes.

Multiparametric Magnetic Resonance Imaging of Penile Cancer: A Pictorial Review

The role of multiparametric magnetic resonance imaging (mpMRI) in assessing penile cancer is not well defined. However, this modality may be successfully applied for preoperative staging and patient selection; postoperative local and regional surveillance; and assessments of treatment response after oncological therapies. Previous studies have been mostly limited to a few small series evaluating the accuracy of MRI for the preoperative staging of penile cancer. This review discusses the principles of non-erectile mpMRI, including functional techniques and their applications in evaluating the male genital region, along with clinical protocols and technical considerations. The latest clinical classifications and guidelines are reviewed, focusing on imaging recommendations and discussing potential gaps and disadvantages. The development of functional MRI techniques and the extraction of quantitative parameters from these sequences enables the noninvasive assessment of phenotypic and genotypic tumor characteristics. The applications of advanced techniques in penile MRI are yet to be defined. There is a need for prospective trials and feasible multicenter trials due to the rarity of the disease, highlighting the importance of minimum technical requirements for MRI protocols, particularly image resolution, and finally determining the role of mpMRI in the assessment of penile cancer.

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.

Radioisotope-Guided Sentinel Lymph Node Biopsy in Penile Cancer: A Long-Term Follow-Up Study

Lymph node (LN) management is critical for survival in patients with penile cancer. However, radical inguinal lymphadenectomy carries a high risk of postoperative complications such as lymphedema, lymphocele, wound infection, and skin necrosis. The European Association of Urology guidelines therefore recommend invasive LN staging by modified inguinal lymphadenectomy or dynamic sentinel node biopsy (DSNB) in clinically node-negative patients (cN0) with intermediate- and high-risk tumors (≥ T1G2). However, the timing of DSNB (simultaneous vs. subsequent to partial or total penile resection) is controversial and the low incidence of penile cancer means that data on the long-term outcomes of DSNB are limited. The present study aimed to analyze the reliability and morbidity of DSNB in patients with penile cancer during long-term follow-up. This retrospective study included 41 patients (76 groins) who underwent radioisotope-guided DSNB simultaneously or secondarily after penile surgery from June 2004 to November 2018. In total, 193 sentinel LNs (SLNs) and 39 non-SLNs were removed. The median number of dissected LNs was 2.5 (interquartile range 2-4). Histopathological analysis showed that five of the 76 groins (6.6%) contained metastases. None of the non-SLNs were tumor-positive. In accordance with the guidelines, all inguinal regions with positive SLNs underwent secondary radical inguinal lymphadenectomy, which revealed three additional metastases in one groin. Regional LN recurrence was detected in three patients (four groins) during a median follow-up of 70 months, including two patients in whom DSNB had been performed secondarily after repetitive penile tumor resections. DSNB-related complications occurred in 15.8% of groins. Most complications were mild (Clavien-Dindo grade I; 50%) or moderate (II; 25%), and invasive intervention was only required in 3.9% of groins (IIIa: n = 1; IIIb: n = 2). In summary, this study suggests that the current radioisotope-guided DSNB procedure may reduce the complication rate of inguinal lymphadenectomy in patients with cN0 penile cancer. However, DSNB and penile surgery should be performed simultaneously to minimize the false-negative rate. Recent advances, such as new tracers and imaging techniques, may help to reduce the false-negative rate of DSNB further.

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.

A proposed Clino-radio-pathological Risk Scoring System (CRiSS) for prediction and management of inguinal lymph-nodes metastasis in squamous cell carcinoma of the penis

OBJECTIVE

To develop a risk scoring system for prediction of inguinal lymph-node involvement and to suggest a management strategy according to the risk groups based on clinical, radiological and pathological parameters in squamous cell carcinoma (SCC) of penis.

MATERIALS AND METHODS

A retrospective analysis of all patients of SCC penis from 2014 to 2020 at our institute was done. The patients were divided into derivation cohort (2014 to 2019) and validation cohort (2019 to 2020). A total of 10 predictors were analysed in univariate analysis and those found significant were further subjected to multivariate analysis to derive regression coefficient for each. CRiSS scores were assigned based on the coefficients and three groups were created which were correlated with nodal metastasis. The predictive accuracy of the model was assessed by ROC analysis of the derivation cohort and validation cohort.

RESULTS

A total of 102 patients were identified in derivation cohort and 23 patients in validation cohort. Size of the primary >3cm, ulceroinfiltrative growth, involving shaft, ultrasound size of lymph-nodes >1cm, loss of fatty hila, moderate and poor differentiation, and lypmphovascular/perineural invasion were independent predictors of inguinal lymphnode metastasis in multivariate analysis. CRiSS could achieve AUROC of .910 and .887 in derivation and validation cohort respectively. The rate of metastatic lymphadenopathy was 0%, 41.4%, and 89.5% in low, intermediate, and high-risk groups respectively.

CONCLUSIONS

CRiSS can effectively predict inguinal lymph-node metastasis in SCC penis. We suggest a management strategy based on risk groups that will avoid morbidity of groin dissection in many patients.

Organ preserving radiation strategies for penile cancer

INTRODUCTION

The majorities of penile cancers are of squamous cell origin and thus are amenable to treatment and cure by radiation. Despite the move toward penile sparing strategies, radiation remains an under-utilized and often neglected option. This paper will review the various radio-therapeutic approaches for penile cancer and the literature supporting their use. English, French and Spanish literature on penile cancer was reviewed for the past 5 decades and classified according to modality: external beam radiotherapy, interstitial brachytherapy and surface mold brachytherapy. Many series span several decades and include a wide range of stages, especially for external beam radiotherapy. Penile preservation obviously will depend on dose prescription and stage at treatment. Nonetheless, in general, penile sparing with external beam ranges from 36% to 66% at 5 years. For the selected patients appropriate for interstitial brachytherapy penile sparing is 77% to 87% at 5 years, decreasing to 70% at 10 years. Mold therapy is selected for those with very superficial disease and penile sparing is consequently higher.

CONCLUSIONS

The development of centers of excellence for the management of this uncommon disease is encouraged. The required surgical and radiotherapy skill sets cannot be expected to be available in all centers. A multidisciplinary evaluation of each patient will facilitate selection of optimal management from the outset.

Pelvic lymph nodes and pathways of disease spread in male pelvic malignancies

PURPOSE

Accurate nodal staging for male urogenital malignancies has important implications for therapy and prognosis. Male pelvic malignancies, including prostatic, penile, testicular, and bladder cancer, typically metastasize to regional lymph nodes first which is reported by the N-stage. Spread beyond these groups to non-regional nodes is regarded as M-stage disease.

METHODS

In this review, we discuss the typical patterns of male pelvic lymphatic drainage and the tumor-specific regional nodal chains.

RESULTS

The impact of tumor-specific imaging features and the implications of previous treatments on staging are discussed.

CONCLUSIONS

While anatomic imaging, including CT and MRI, is the most widely employed imaging modality at present, newer functional imaging techniques have demonstrated promise in the accurate identification and characterization of nodal metastases.

High TRIAP1 expression in penile carcinoma is associated with high risk of recurrence and poor survival

Background

TP53-regulated inhibitor of apoptosis 1 (TRIAP1), also known as p53 cell survival factor or p53CSV, is reported to be associated with resistance of apoptosis in different human malignancies, but the potential role of TRIAP1 in penile carcinoma (PeCa) has not been well studied. This study aimed to analyze the association between TRIAP1 expression and clinical outcome in PeCa patients.

Methods

Bioinformatics was used to analyze the differential TRIAP1 expression in PeCa compared with normal tissues in Gene Expression Omnibus (GEO) Dataset (GSE57955). The expression of TRIAP1 in tumor specimens from 57 patients undergoing radical penile surgery was detected by immunohistochemistry (IHC). Differential TRIAP1 expression in various human malignancies was also assessed by GEPIA web-tool based on The Cancer Genome Atlas (TCGA) Datasets. Subsequently, the relationship between TRIAP1 expression and clinical prognosis of PeCa patients was analyzed.

Results

Both IHC and GEO Dataset (GSE57955) showed that TRIAP1 was significantly overexpressed in PeCa tissues when compared with normal tissues. Based on patient data and IHC on clinical specimens, we found that strong intensity of TRIAP1 expression was significantly related with higher histological grade (P=0.049) and elevated local recurrence rate (P=0.023), suggesting TRIAP1 as a potential predictor in recurrence. Further, high TRIAP1 expression was identified to be a hazardous prognostic factor for local recurrence-free survival (RFS).

Conclusions

High TRIAP1 expression in PeCa is associated with high risk of recurrence and poor survival, suggesting TRIAP1 may become a potential prognostic factor for PeCa.