Penile secondary lesions: a rare entity detected by PET/CT

68 Ga-PSMA-11 PET/CT and 64 CuCl 2 PET/CT Help in Identifying Rare Metastatic Site of Penile Shaft in a Patient of Carcinoma Prostate

ABSTRACT

A 71-year-old man, presenting with complaints of burning sensation and pain during urination, finally diagnosed with prostate carcinoma. Ultrasonography of the abdomen and pelvis revealed prostatomegaly. Serum PSA level was elevated, and TRUS-guided biopsy demonstrated acinar adenocarcinoma (Gleason score: 5 + 4 = 9). 68 Ga-PSMA-11 PET/CT for initial staging showed PSMA-avid enlarged prostate, pelvic lymphadenopathy, and focal PSMA uptake in the left side of the shaft of the penis. The patient also underwent a 64 CuCl 2 PET/CT, which demonstrated similar findings of enlarged prostate and adenopathy with focally increased tracer uptake in the shaft of the penis coinciding with the lesion observed on 68 Ga-PSMA-11 PET/CT, thereby detecting a rare metastatic site from carcinoma prostate.

Unusual Case of Missed Penile Metastases on 68Ga-PSMA PET/CT

ABSTRACT

A 75-year-old man with a history of previously treated localized prostate cancer and prostate-specific antigen of 4.86 ng/mL was referred for a 68Ga-prostate-specific membrane antigen PET/CT. PET imaging was reported to be negative. After subsequent review and re-read of the scan, prostate-specific membrane antigen imaging revealed uptake along the penile shaft (SUVmax of 14.7). MRI was compatible with tumor. Penile metastases from prostate cancer, although uncommon, do occur and readers are encouraged to distinguish penile metastatic uptake from residual urine in the urethra.

An unusual, delayed, solitary manifestation of a penile lesion in chronic lymphocytic leukemia

Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in the adult western population. It is characterized by the proliferation of mature but dysfunctional lymphocytes, primarily CD5+ B cells. It primarily affects the reticuloendothelial system in the majority of the cases, but can rarely manifest as extranodal and extramedullary lesions. One of the rare presentations is genitourinary cutaneous infiltration, and only a handful of cases of secondary metastases to the genitourinary skin, have been reported in the literature. The current report describes a patient with solitary lesion of CLL in the penis, manifesting almost two decades after the complete treatment of CLL.

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.

Case Report: 18F-PSMA-1007 PET/CT Avid Solitary Penile Metastasis of Castration-Resistant Prostate Cancer With a PSA of 0.072 ng/ml

Penile metastasis of prostate cancer is rare, with a poor prognosis, and only a limited number of relevant cases have been reported so far. With the application of ¹⁸F-PSMA-1007 PET/CT, the biochemical recurrence of prostate cancer can be detected at an early stage for providing important evidence, facilitating clinical decision-making. Here, we have reported a case of solitary penile metastatic recurrence in the context of mild PSA progression (PSA: 0.072 ng/ml). This case highlights the preferable sensitivity of ¹⁸F-PSMA-1007 PET/CT imaging in prostate cancer.

Case Report: 18F-PSMA PET/CT May Improve the Clinical Management of Penile Metastases From Prostate Cancer

Metastases from prostate cancer (PCa) to the penis are extremely rare, and few case reports exist in the literature. Because most patients usually present with multiple distant metastases at diagnosis, the prognosis is very poor. With the wide application of prostate-specific membrane antigen (PSMA) PET/CT, penile metastases may be detected at an early stage. Thus, questions regarding whether early diagnosis and precise treatment will equate to a survival advantage have recently been raised. In the present study, we reported 3 cases of penile metastasis from castration-resistant PCa. Moreover, a patient with asymptomatic penile metastases was diagnosed by ¹⁸F-PSMA PET/CT followed by lesion biopsy, and the prognosis was very well, despite with an aggressive pathological feature and low treatment intensity. In addition, we performed a literature review and found 62.5% of asymptomatic penile metastases were diagnosed by PSMA PET/CT in past seven years. Thus, we believe that PSMA PET/CT may detect more asymptomatic penile metastases in future, which led to early diagnosis, treatment and survival advantage.