Which of the following is NOT a risk factor for penile carcinoma?
Answer C
All the above except chlamydial infection predisposes to SCC of the penis. BXO or lichen sclerosus et atrophicus is now also believed to be a risk factor.
Which of these tumour markers is NOT associated with penile squamous cell carcinoma?
Answer D
Herpes Simplex Virus-2 (HSV-2) is a sexually transmitted chronic infection of the genital tract and is not a biomarker for SCC of the penis. Other markers associated with penile SCC include p16INK4A, MMP-2, HPV DNA, PTEN, HER3/4 and miRNA.
With regards to the mechanism of action of 5 Flurouracil (5-FU) cream for erythroplasia of Queyrat (EQ). Which of the following is TRUE?
Topical 5 FU is structurally similar to thymine and blocks DNA synthesis by inhibiting thymidylate synthetase. In contrast Imiquimod is an imidazoquinonin tetracyclicamine which alters the immune response by possibly inducing interferon alpha.
What would be the EAU recommended first-line treatment for a man with a biopsy proven SCC on the glans penis that is confined to the corpus spongiosus on staging MRI (cT2 disease)?
Glansectomy with a split-thickness skin graft would be the standard operation in the UK. Penile preserving surgery has proven equivalent oncological outcomes to radical surgery with the benefits of improved sexual, urinary and psychological results. Radical radiotherapy tends to be reserved for older patients not fit for surgery or for patients who have refused surgery. This is mainly due to its higher recurrence rate (up to 40%) and associated morbidity, which includes penile necrosis requiring amputation.
Which of the following is dynamic sentinel lymph node biopsy (DSLNB) for staging in patients with proven SCC of the penis indicated for?
In patients with clinically impalpable inguinal nodes at presentation, around 20% will harbour occult lymph node metastases. If all patients went onto have inguinal lymph node dissections 80% would be over treated and exposed to the morbidity of surgery. In an attempt to identify the 20% of patients with metastatic disease and avoid the unnecessary morbidity in the other 80% the technique of DSLNB was developed.
It is well accepted that penile cancers spread by embolisation via the lymphatics in a predictable stepwise fashion to the inguinal and then to the iliac nodes. The concept of sentinel lymph node biopsy was first described in men with penile cancer in 1977 by Cabanas. Unfortunately, due to a high false negative rate (FNR) and lack of reproducibility the technique fell out of favour until several modifications were made in the mid 1990s. The FNR of the DSLNB technique in penile cancer patients has been reduced to around 5%. The technique has been shown to be reproducible and has a short learning curve in the hands of penile cancer centres.
To identify the SLN pre operative mapping with Technetium 99m (Tc99m) labelled nanocolloid is essential. Intra operatively a handheld gamma probe is used to detect the ‘hot’ nodes and injected patent blue dye helps visualise the SLNs. The addition of preoperative ultrasound and fine needle aspiration cytology, intraoperative palpation and immunohistochemical stains have also helped to reduce the FNR.
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