Abstract 784P
Background
The role of perioperative treatment with adjuvant radiotherapy (RT), combination chemotherapy (CT) or both modalities in node-positive penile cancer following radical lymphadenectomy is unclear. Recent guidelines suggest a benefit of perioperative CT, but question the efficacy of adjuvant RT.
Methods
Perioperative combination CT using paclitaxel/cisplatin/ifosfamade (TIP) or Cisplatin/5FU (CF) was added to our protocol of adjuvant RT in high-risk, node-positive squamous cell carcinoma of the penis. From 2007 to 2018 a total of 111 patients were treated with radical surgery including inguinal lymphadenectomy for pN2/pN3 disease at a supraregional centre. 9 were excluded due to metastatic disease at presentation and 10 were excluded due to lack of follow up. 92 patients were included in the analysis. Primary outcome was progression free survival (PFS) 2 years after surgery. Log-rank analysis of survival curves, and multivariate analysis (MVA) using Cox proportional hazard logistic regression was undertaken.
Results
Median age was 62 years. 57% (52/92) had extranodal extension (ENE). 43% (40/92) also underwent pelvic lymphadenectomy. 48% (44/92) received post-operative RT, the most recent 19% also had perioperative chemotherapy (most had TIP). The PFS at 24 months was 26% with post-operative surveillance alone, 54% with post-operative RT alone and 74% with both perioperative CT and post-operative RT. Surveillance versus RT alone resulted in PFS 7 versus 36 months, HR 2.01 (1.2-3.8) p=0.0079. Surveillance vs CT + RT PFS 7 months versus PFS not reached HR 3.4 (1.6-7) P=0.0008. MVA confirmed that CT + RT reduced risk of progression HR 0.2 (0.05-0.92) p=0.039 (Table). Table: 784P
| Perioperative intervention | 2 year PFS | Median PFS | HR | 95% CI | P |
| Surveillance | 26% | 7 months | - | - | - |
| Adj RT alone | 54% | 36 months | 2.8 | 1.2-3.8 | 0.0079 |
| CT and RT | 74% | not reached | 3.4 | 1.7-7.0 | 0.0008 |
| MVA- variables associated with risk of progression after surgery | HR | 95% CI | P | ||
| surveillance | 2.1 | 1.2-3.9 | 0.013 | ||
| Combination RT and CT | 0.2 | 0.1-0.9 | 0.039 | ||
| Extracapsular Spread | 2.1 | 1.1-3.9 | 0.019 |
Conclusions
Following inguinal lymphadenectomy in high-risk node-positive penile cancer patients PFS was significantly improved in patients who received adjuvant RT alone, but the greatest PFS was seen in those who receive both perioperative CT and adjuvant RT.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The authors.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.