Updates in the use of radiotherapy in the management of primary and locally-advanced penile cancer

Brachytherapy and external beam radiation in the management of primary penile cancer - Game changer for organ preservation?

OBJECTIVE

In squamous cell carcinoma of the penis (PeCa), treatment options for primary tumors vary by disease stage and may include surgery, radiation, topical chemotherapy, or laser excision. This review aims to highlight the current evidence on the value of radiotherapy as an organ-preserving strategy in primary PeCa.

MATERIAL AND METHODS

Manuscripts on primary PeCa treatment with external beam radiotherapy (EBRT) and brachytherapy were evaluated via Scopus, PubMed/MEDLINE, and Web of ScienceTM (2013-2023) to assess their efficacy and safety. Animal studies, studies with <5 patients, and case reports were excluded.

RESULTS

Radiotherapy offers the potential for organ preservation with tumor control rates comparable to radical surgery, while disease-specific survival rates up to 70 % were experienced with EBRT. Brachytherapy (BT) is the preferred method of irradiation for glans-limited tumors, whereas a higher relapse risk is expected for tumors >4 cm. BT shows 73 % amputation-free survival at 8-10 years and 81 % progression-free survival at 5-10 years. Compared with BT, total amputation significantly improves 5-year disease-free survival rate. BT offers a superior 5-year local control and penile preservation rates compared to EBRT. Common acute toxicities of brachytherapy include radiodermatitis, sterile urethritis, and urethral adhesions. The primary late adverse events of BT are soft tissue necrosis (0-31 %) and meatal stenosis (0-43 %).

CONCLUSION

BT is a favorable radiation modality, offering an efficient and conservative approach. HDR BT is favored for its enhanced dose distribution and radiation protection. Collaboration between radiation oncologists and urologists is essential in order to provide an optimal patient selection and manage toxicities thus optimizing patient outcomes.

Penile cancer: ESMO-EURACAN Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO CPG provides recommendations for diagnosis, staging, pathology, treatment and follow-up of penile cancer. •Algorithms for the management of primary penile tumours and inguinal lymph nodes are provided. •The author group encompasses a multidisciplinary group of experts from different institutions and countries in Europe. •Recommendations are based on available scientific data and the authors’ collective expert opinion. •In clinical practice, all recommendations provided need to be discussed with patients in a shared decision-making approach.

A Technique to Deliver Conformal External Beam Radiation for Squamous Carcinoma of the Penile Glans and Urethra

This study presents an approach to external beam radiation therapy for treating penile cancer using a small water bath. This modified technique involves the use of an acrylic, cuboid-shaped water bath with dimensions 6 × 6 × 8 cm3. The water bath is filled with readily available saline solution maintained at room temperature. The patient is positioned in the prone position, and the penis is placed within the water bath. The isocenter is set at the center of the water bath, and bilateral beams are positioned at 89.1° and 270.9°. The proposed technique was evaluated based on dose calculations, demonstrating a clinical target volume dose with a Dmax of 103.5% and a Dmin of 100.0% of the prescribed dose. Additionally, the method showed a low organs-at-risk dose, with a Dmean of only 1% for the testicles. The treatment zone inside the water bath also showed a uniform dose distribution. This technique not only offers high treatment efficiency and more accurate dose distribution to the targeted area but also provides additional benefits, including reduced toxicity to organs at risk and increased device utilization efficiency. In conclusion, the proposed modified external beam radiation therapy method presents a promising alternative for patients with penile cancer, enhancing treatment precision and safety.

The Utility of Salvage Radiotherapy for an Inoperable Inguinal Recurrence of Squamous Cell Carcinoma of the Penis

Penile cancer is a rare genitourinary malignancy for which limited treatment options exist beyond primary surgical resection. Metastatic lymphadenopathy represents a particularly poor prognosis with a lack of literature to suggest the effectiveness of radiation or systemic therapies. Our case documents an inguinal recurrence of penile squamous cell carcinoma not amenable to surgical intervention demonstrating complete response to salvage radiotherapy in the palliative setting. These observations propose the need for further research around the utility of radiotherapy in the management of metastatic penile malignancies.

The Prognostic Role of Human Papillomavirus and p16 Status in Penile Squamous Cell Carcinoma-A Systematic Review

PSCC is a rare cancer, with approximately half of all cases related to HPV. While HPV and p16 IHC testing have proven their prognostic value for oropharyngeal cancer, this is not yet established for PSCC. The current level of evidence exploring the relation between PSCC and HPV is moderate, so we conducted a systematic review following PRISMA guidelines to evaluate the prognostic role of HPV and p16 IHC in PSCC clinical outcomes. We searched the PubMed, Embase, and Cochrane databases and identified 34 relevant studies that met our inclusion criteria. Of these, 33 were retrospective cohort studies, and one was a cross-sectional study. Nine studies reported that HPV-positive and p16-positive PSCC had better overall survival (OS) and disease-free survival (DFS). This study highlights the need for a meta-analysis to determine the role of routine HPV status or p16 staining testing as part of the initial diagnosis and staging of PSCC patients worldwide.

Organ-sparing treatment for T1 and T2 penile cancer: an updated literature review

PURPOSE OF REVIEW

Penile cancer (PeCa) is an orphan disease due to its rare incidence in high-income countries. Traditional surgical options for clinical T1-2 disease, including partial and total penectomy, can dramatically affect patient's quality of life and mental health status. In selected patients, organ-sparing surgery (OSS) has the potential to remove the primary tumor with comparable oncologic outcomes while maintaining penile length, sexual and urinary function. In this review, we aim to discuss the indications, advantages, and outcomes of various OSSs currently available for men diagnosed with PeCa seeking an organ-preserving option.

RECENT FINDINGS

Patient survival largely depends on spotting and treating lymph node metastasis at an early stage. The required surgical and radiotherapy skill sets cannot be expected to be available in all centers. Consequently, patients should be referred to high-volume centers to receive the best available treatments for PeCa.

SUMMARY

OSS should be used for small and localized PeCa (T1-T2) as an alternative to partial penectomy to preserve patient's quality of life while maintaining sexual and urinary function and penile aesthetics. Overall, there are different techniques that can be used with different response and recurrence rates. In case of tumor recurrence, partial penectomy or radical penectomy is feasible, without impacting overall survival.