DaPeCa-3: promising results of sentinel node biopsy combined with (18) F-fluorodeoxyglucose positron emission tomography/computed tomography in clinically lymph node-negative patients with penile cancer - a national study from Denmark.

OBJECTIVES: To estimate the diagnostic accuracy of sentinel node biopsy (SNB) combined with preoperative (18) F-fluorodeoxyglucose positron emission tomography/computed tomography (FDG PET/CT) for inguinal lymph node (LN) evaluation in patients with invasive penile squamous cell carcinoma (PSCC) with no clinical evidence of inguinal metastases (cN0) at two tertiary centres with complete clinical follow-up. PATIENTS AND METHODS: From April 2010 in Centre one and from January 2013 in Centre two, we prospectively enrolled patients diagnosed with invasive PSCC and scheduled for SNB at the only two university centres treating penile cancer in Denmark. All patients had FDG PET/CT before SNB. The sentinel LNs were preoperatively located by planar lymphoscintigraphy in 134 groins (68 patients) and by single-photon emission CT/CT in 120 groins (61 patients). The primary endpoints were the sensitivity, specificity, and false-negative rate of SNB combined with FDG PET/CT. The secondary endpoint was SNB-related morbidity. RESULTS: We examined 254 groins in 129 patients by SNB combined with FDG PET/CT. The median (interquartile range, IQR) follow-up of survivors was 23 (14-35) months. Of 201 LN-negative groins, two were false negatives, and despite radio-chemotherapy treatment, both patients died from penile cancer. Four of 23 radiotracer-silent groins, had a FDG PET/CT-positive LNs and were surgically explored. In one of four of the explored groins, a positive LN was found. Combined FDG PET/CT-SNB sensitivity was 94.4% (95% confidence interval [CI] 81-99%) per groin. The false-negative rate was 5.6% (95% CI 1-19%) per groin. In 15 patients (11.6%) there were 25 SNB-related complications of Clavien-Dindo grades I-IIIa. The only Clavien-Dindo IIIa complication was an inguinal lymphocele treated by aspiration. CONCLUSION: In this study, we present a favourable SNB false-negative rate of 5.6% in a national cohort of clinically LN-negative patients with invasive PSCC with a pre-SNB FDG PET/CT scan. The combination of FDG PET/CT and SNB seems to be a promising diagnostic approach. Even so, a false-negative SNB was fatal in two of two cases and we are determined to continue the development of our SNB technique. The SNB-related morbidity was limited.

DaPeCa-1: diagnostic accuracy of sentinel lymph node biopsy in 222 patients with penile cancer at four tertiary referral centres - a national study from Denmark.

OBJECTIVES: To estimate the diagnostic accuracy of sentinel lymph node biopsy (SNB) in patients with penile cancer and assess SNB complications in a national multicentre setting. PATIENTS AND METHODS: Retrospectively data were collected from records in four university centres by one medical doctor covering all SNBs performed in Denmark between 1 January 2000 and 31 December 2010. Patients had either impalpable lymph nodes (LNs) in one or both groins, or had a palpable inguinal mass from which aspiration cytology failed to reveal malignancy. Patients were injected with nanocolloid technetium and had a scintigram recorded before the SNB. The primary endpoint was LN recurrence on follow-up. The secondary endpoint was complications after SNB. Diagnostic accuracy was computed. RESULTS: In all, 409 groins in 222 patients were examined by SNB. The median (interquartile range) follow-up of patients who survived was 6.6 (5-10) years. Of 343 negative groins, eight were false negatives. The sensitivity was 89.2% (95% confidence interval 79.8-95.2%) per groin. Interestingly, four of 67 T1G1 patients had a positive SNB. In all, 28 of 222 (13%) patients had complications of Clavien-Dindo grade I-IIIa. CONCLUSION: Penile cancer SNB with a close follow-up stages LN involvement reliably and has few complications in a national multicentre setting. Inguinal LN dissection was avoided in 76% of patients.