An epidemiological and clinicopathological study of type 1 vs. type 2 morphological subtypes of papillary renal cell carcinoma- results from a nation-wide study covering 50 years in Iceland.

INTRODUCTION: Papillary renal cell carcinoma (pRCC) is the second most common histology of renal cell carcinoma (RCC), accounting for 10-15% of cases. Traditionally, pRCC is divided into type 1 and type 2, although this division is currently debated as a prognostic factor of survival. Our aim was to investigate the epidemiology and survival of the pRCC subtypes in a whole nation cohort of patients during a 50-year period. MATERIALS AND METHODS: A Population based retrospective study including consecutive cases of RCC in Iceland from 1971-2020. Comparisons were made between histological classifications of RCC, with emphasis on pRCC subtypes (type 1 vs. 2) for outcome estimation. Changes in RCC incidence were analyzed in 5-year intervals after age standardization. The Kaplan-Meier method and Cox regression were used for outcome analysis. RESULTS: A total of 1.725 cases were identified, with 74.4%, 2.1% and 9.2% having clear cell (ccRCC), chromophobe (chRCC), and pRCC, respectively. The age standardized incidence (ASI) of pRCC was 1.97/100.000 for males and 0.5/100.000 for females, and the proportion of pRCC increased from 3.7% to 11.5% between the first and last intervals of the study (p < 0.001). Age standardized cancer specific mortality (ASCSM) of pRCC was 0.6/100.000 and 0.19/100.000 for males and females, respectively. The annual average increase in ASI was 3.6% for type 1 pRCC, but the ASI for type 2 pRCC and ASCSM for both subtypes did not change significantly. Male to female ratio was 4.4 for type 1 pRCC and 2.3 for type 2. The average tumor size for type 1 and 2 was 58.8 and 73.7 mm, respectively. Metastasis at diagnosis was found in 8.7% in the type 1 pRCC, compared to 30.0% of patients with type 2 pRCC (p < 0.001). Estimated 5-year cancer-specific survival (CSS) were 94.4%, 80.7%, and 69.3% for chRCC, pRCC and ccRCC, respectively (p < 0.001). For the pRCC subtypes, type 1 was associated with better 5-year CSS than type 2 (86.3% vs. 66.0%, p < 0.001), although this difference was not significant after adjusting for cancer stage and grading. CONCLUSIONS: pRCC histology was slightly less common in Iceland than in other countries. Males are more than three times more likely to be diagnosed with pRCC, compared to other RCC histologies. The subtype of pRCC was not found to be an independent risk factor for worse survival, and as suggested by the most recent WHO Classification of Urinary Tumors, grade and TNM-stage seem to be the most important factors for estimation of survival for pRCC patients.

A successful shift from thoracotomy to video-assisted thoracoscopic lobectomy for non-small cell lung cancer in a low-volume center.

OBJECTIVES: Although video-assisted thoracoscopic surgery (VATS) lobectomy has become the gold standard for pulmonary resections of non-small-cell lung cancer (NSCLC), lobectomy is still performed via thoracotomy in many European and North American centres. VATS lobectomy was implemented overnight from thoracotomy in our low-volume centre in early 2019, after 1 senior surgeon undertook observership VATS-training overseas, and immediately became the mainstay of surgical treatment for NSCLC in Iceland. We aimed to investigate our short-term outcomes of VATS lobectomy. METHODS: This was a retrospective study on all pulmonary resections for NSCLC in Iceland 2019-2022, especially focusing on VATS lobectomies, all at cTNM stage I or II. Data were retrieved from hospital charts, including information on perioperative complications, mortality, length of stay and operation time. RESULTS: Out of 204 pulmonary resections, mostly performed by a single senior cardiothoracic surgeon, 169 were lobectomies (82.9%) with 147 out of 169 (87.0%) being VATS lobectomies. Anterolateral thoracotomy was used in 34 cases (16.7%), including 22 lobectomies (64.7%), and 5 (3.4%) conversions from VATS lobectomy. The median postoperative stay for VATS lobectomy was 4 days and the average operating time decreased from 155 to 124 min between the first and last year of the study (P < 0.001). The rate of major and minor complications was 2.7% and 15.6% respectively. One year survival was 95.6% and all patients survived 30 days postoperatively. CONCLUSIONS: The implementation of VATS lobectomy has been successful in our small geographically isolated centre, serving a population of 390 000. Although technically challenging, VATS lobectomy was implemented fast for most NSCLC cases, with short-term outcomes that are comparable to larger high-volume centres.