High-dose rate brachytherapy in localized penile cancer: 5-Year clinical outcome analysis

The role of radiotherapy in the management of squamous cell cancer of the penis

PURPOSE

To review the evidence for radiotherapy in the management of primary penile cancer, either as brachytherapy or external beam radiation, and the role of external beam radiotherapy in node positive penile cancer.

METHODS

English language literature was reviewed for the past 3 decades. As penile cancer is uncommon in developed nations, high quality evidence to guide management is limited. Single institution reports often span decades during which time staging systems and treatments have evolved, reducing their relevance to current practice. Successful clinical trials require collaboration not only among disciplines but also among multiple institutions and nations.

RESULTS

Radiotherapy is a definitive organ-preserving option for T1-T2 penile cancers. Interstitial brachytherapy is associated with penile preservation in 85% of men at 5 years, maintained in 70% by 10 years. Results of external radiotherapy are not quite as promising but nonetheless 60% of men will have an intact penis at 5 years. Inguino-pelvic external radiotherapy has been reported to increase overall survival when delivered as adjuvant treatment for men with pN3 groin but pN0 pelvic nodes, and improve disease specific survival for those with involved pelvic nodes. InPACT (ECOG-ACRIN_8134) is investigating the role of inguino-pelvic chemo-radiotherapy for men with pN3 inguinal nodes but imaging negative pelvic nodes.

CONCLUSIONS

Radiotherapy has a well-defined role to play in treatment of squamous cell cancers of other sites, such as vulva, anal canal, uterine cervix and head and neck malignancies. Emerging data support the incorporation of radiotherapy into treatment paradigms for penile cancer.

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.

Function Preservation With Brachytherapy: Reviving the Art. Improving Quality of Life With Brachytherapy for Urological Malignancies

Brachytherapy for localised prostate, muscle-invasive bladder and penile cancer is well established, providing high tumour dose delivery and minimising normal tissue doses compared with external beam techniques. In prostate cancer, the main impact on quality of life relates to diminished sexual function and irritative or obstructive urinary symptoms, which are seen up to 15 years after treatment. Significant changes in bowel function are rare. Compared with radical prostatectomy or external beam radiotherapy, irritative or obstructive urinary symptoms are more prominent, whereas incontinence is less than after radical prostatectomy and bowel changes are less than after external beam radiotherapy. For muscle-invasive bladder cancer, when compared with radical cystectomy, although no difference is seen for urinary symptoms or fatigue, role and social functioning scores are higher and there is better post-treatment sexual function in both men and women. Compared with surgical treatment for penile cancer, brachytherapy results in better erectile function scores than after glansectomy and partial penectomy and high quality of life scores, with good satisfaction ratings for cosmetic appearance.

High-Dose-Rate Brachytherapy as an Organ-Sparing Treatment for Early Penile Cancer

BACKGROUND

Low-dose-rate brachytherapy is an effective organ-sparing treatment for patients with early-stage penile cancer. However, only limited data are available on the role of high-dose-rate brachytherapy (HDR-BT) in this clinical setting.

METHODS

Between 2002 and 2020, 31 patients with early penile cancer were treated at our center with interstitial HDR BT at a dose of 18 × 3 Gy twice daily. A breast brachytherapy template was used for the fixation of stainless hollow needles.

RESULTS

The median follow-up was 117.5 months (range, 5-210). Eight patients (25.8%) developed a recurrence; of these, seven were salvaged by partial amputation. Six patients died of internal comorbidities or a second cancer. The probability of local control at 5 and 10 years was 80.7% (95% CI: 63.7-97.7%) and 68.3% (95% CI: 44.0-92.6%), respectively. Cause-specific survival was 100%. Only one case of radiation-induced necrosis was observed. The probability of penile sparing at 5 and 10 years was 80.6% (95% CI: 63.45-97.7%) and 62.1% (95% CI: 34.8-89.4%), respectively.

CONCLUSIONS

These results show that HDR-BT for penile cancer can achieve results comparable to LDR-BT with organ sparing. Despite the relatively large patient cohort-the second largest reported to date in this clinical setting-prospective data from larger samples are needed to confirm the role of HDR-BT in penile cancer.

Novel portable apparatus for outpatient high-dose-rate (HDR) brachytherapy in penile cancer

BACKGROUND

Penile squamous cell carcinoma (PSC) is traditionally treated with surgical resection with significant morbidity. Penile sparing approaches, such as brachytherapy, require expertise, prolonged inpatient stays, poor patient convenience, and heterogenous plans with variable long-term toxicity. In this study, we describe the protocol for novel portable apparatus created for PSC, allowing outpatient hybrid interstitial/surface brachytherapy, improving homogeneity and patient convenience.

METHODS

A portable brachytherapy apparatus was developed utilizing a foley catheter, prostate template, 6F interstitial catheters, 5 mm bolus, and a jock strap. The apparatus allowed for internal and external catheter placement housed in a jock strap to allow mobility and defecation without affecting the implant. High-dose-rate brachytherapy was performed as an outpatient.

RESULTS

The apparatus was then used on a 62-year-old male with cT2pN0M0 (stage IIA) PSC with bilateral glans and urethral meatus involvement, who elected for definitive brachytherapy (4000cGy in 10 fractions over 5-days). Given external dwell positions, heterogeneity correction of the template was calculated (AAPM TG186) with <2% variation. Patient had minimal impact on his active lifestyle during treatment and had complete clinical response at 3-months. Grade 2 skin desquamation resolved at 2-months, with no necrosis. At 6-months, he was able to resume sexual intercourse, and at 12-months, he remained disease-free with sexual and urinary function intact.

CONCLUSIONS

Novel portable implant allows for improved patient convenience, reduced inpatient stay, capable of optimizing dosimetry with hybrid brachytherapy. This outpatient treatment allows the opportunity to increase fractionation, offering high local-control and lower toxicity. Future studies utilizing this apparatus for more fractionated regimens with further lower dose-per-fraction (∼3 Gy/fraction) is recommended.

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

Objective

Penile cancer is a rare malignancy in most developed countries, but may represent a significant oncologic challenge in certain African, Asian, and South American regions. Various treatment approaches have been described in penile cancer, including radiotherapy. This review aimed to provide a synopsis of radiotherapy use in penile cancer management and the associated toxicities. In addition, we aimed to discuss palliative radiation for metastases to the penis and provide a brief overview of how tumor biology may assist with treatment decision-making.

Methods

Peer-reviewed manuscripts related to the treatment of penile cancer with radiotherapy were evaluated by a PubMed search (1960–2021) in order to assess its role in the definitive and adjuvant settings. Selected manuscripts were also evaluated for descriptions of radiation-related toxicity.

Results

Though surgical resection of the primary is an excellent option for tumor control, select patients may be treated with organ-sparing radiotherapy by either external beam radiation or brachytherapy. Data from randomized controlled trials comparing radiotherapy and surgery are lacking, and thus management is frequently determined by institutional practice patterns and available expertise. Similarly, this lack of clinical trial data leads to divergence in opinion regarding lymph node management. This is further complicated in that many cited studies evaluating lymph node radiotherapy used non-modern radiotherapy delivery techniques. Groin toxicity from either surgery or radiotherapy remains a challenging problem and further risk assessment is needed to guide intensification with multi-modal therapy. Intrinsic differences in tumor biology, based on human papillomavirus infection, may help aid future prognostic and predictive models in patient risk stratification or treatment approach.

Conclusion

Penile cancer is a rare disease with limited clinical trial data driving the majority of treatment decisions. As a result, the goal of management is to effectively treat the disease while balancing the importance of quality of life through integrated multidisciplinary discussions. More international collaborations and interrogations of penile cancer biology are needed to better understand this disease and improve patient outcomes.

What Is the Most Effective Management of the Primary Tumor in Men with Invasive Penile Cancer: A Systematic Review of the Available Treatment Options and Their Outcomes

Context

The primary lesion in penile cancer is managed by surgery or radiation. Surgical options include penile-sparing surgery, amputative surgery, laser excision, and Moh’s micrographic surgery. Radiation is applied as external beam radiotherapy (EBRT) and brachytherapy. The treatment aims to completely remove the primary lesion and preserve a sufficient functional penile stump.

Objective

To assess whether the 5-yr recurrence-free rate and other outcomes, such as sexual function, quality of life, urination, and penile preserving length, vary between various treatment options.

Evidence acquisition

The EMBASE, MEDLINE, Cochrane Database of Systematic Reviews, Cochrane Central Register of Controlled Trials (CENTRAL; Cochrane HTA, DARE, HEED), Google Scholar, and ClinicalTrials.gov were searched for publications from 1990 through May 2021. Randomized controlled trials, nonrandomized comparative studies (NRCSs), and case series (CSs) were included.

Evidence synthesis

The systematic review included 88 studies, involving 9578 men from 16 NRCSs and 72 CSs. The cumulative mean 5-yr recurrence-free rates were 82.0% for penile-sparing surgery, 83.9% for amputative surgery, 78.6% for brachytherapy, 55.2% for EBRT, 69.4% for lasers, and 88.2% for Moh’s micrographic surgery, as reported from CSs, and 76.7% for penile-sparing surgery and 93.3% for amputative surgery, as reported from NRCSs. Penile surgery affects sexual function, but amputative surgery causes more appearance concerns. After brachytherapy, 25% of patients reported sexual dysfunction. Both penile-sparing surgery and amputative surgery affect all aspects of psychosocial well-being.

Conclusions

Despite the poor quality of evidence, data suggest that penile-sparing surgery is not inferior to amputative surgery in terms of recurrence rates in selected patients. Based on the available information, however, broadly applicable recommendations cannot be made; appropriate patient selection accounts for the relative success of all the available methods.

Patient summary

We reviewed the evidence of various techniques to treat penile tumor and assessed their effectiveness in oncologic control and their functional outcomes. Penile-sparing as well as amputative surgery is an effective treatment option, but amputative surgery has a negative impact on sexual function. Penile-sparing surgery and radiotherapy are associated with a higher risk of local recurrence, but preserve sexual function and quality of life better. Laser and Moh’s micrographic surgery could be used for smaller lesions.

Brachytherapy for oligometastatic prostate cancer to the penis

The origin of penile metastases is in 70% of cases from primary pelvic cancers (genitourinary and recto-sigmoid primary tumors). The prognosis is poor and it is often associated with synchronous bone metastases at the time of diagnosis. We present the case of a 61-year-old patient who developed a penile induration 7 years after radical prostatectomy followed by adjuvant external beam radiation therapy for high-risk prostatic adenocarcinoma. Biopsies confirmed the metastatic localization and a detailed assessment failed to find any further remote lesions. Faced with this penile oligometastatic prostate cancer, we proposed an ablative treatment based on interstitial multi-catheter high-dose rate brachytherapy. At the six-month follow-up, clinical examination and ⁶⁸Ga-PSMA-11-PET confirmed a complete response of the penile tumor without new lesion at a distance.

Does the sequence of high-dose rate brachytherapy boost and IMRT for prostate cancer impact early toxicity outcomes? Results from a single institution analysis

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The optimal sequence of HDR-BT boost and EBRT for prostate cancer is unclear.

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We compared early toxicity based on the timing of HDR-BT boost.

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The timing of HDR-BT was not based on any specific patient or clinical factors.

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We found no difference in early GI/GU toxicity between the two groups.

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Longer follow-up is needed to evaluate late toxicity and long-term disease control.

Background

We present the first report comparing early toxicity outcomes with high-dose rate brachytherapy (HDR-BT) boost upfront versus intensity modulated RT (IMRT) upfront combined with androgen deprivation therapy (ADT) as definitive management for intermediate risk or higher prostate cancer.

Methods and Materials

We reviewed all non-metastatic prostate cancer patients who received HDR-BT boost from 2014 to 2019. HDR-BT boost was offered to patients with intermediate-risk disease or higher. ADT use and IMRT target volume was based on NCCN risk group. IMRT dose was typically 45 Gy in 25 fractions to the prostate and seminal vesicles ± pelvic lymph nodes. HDR-BT dose was 15 Gy in 1 fraction, delivered approximately 3 weeks before or after IMRT. The sequence was based on physician preference. Biochemical recurrence was defined per ASTRO definition. Gastrointestinal (GI) and Genitourinary (GU) toxicity was graded per CTCAE v5.0. Pearson Chi-squared test and Wilcoxon tests were used to compare toxicity rates. P-value < 0.05 was significant.

Results

Fifty-eight received HDR-BT upfront (majority 2014–2016) and 57 IMRT upfront (majority 2017–2018). Median follow-up was 26.0 months. The two cohorts were well-balanced for baseline patient/disease characteristics and treatment factors. There were differences in treatment sequence based on the year in which patients received treatment. Overall, rates of grade 3 or higher GI or GU toxicity were <1%. There was no significant difference in acute or late GI or GU toxicity between the two groups.

Conclusion

We found no significant difference in GI/GU toxicity in intermediate-risk or higher prostate cancer patients receiving HDR-BT boost upfront versus IMRT upfront combined with ADT. These findings suggest that either approach may be reasonable. Longer follow-up is needed to evaluate late toxicity and long-term disease control.