STAGE SPECIFIC GUIDELINES FOR SURVEILLANCE AFTER RADICAL NEPHRECTOMY FOR LOCAL RENAL CELL CARCINOMA:

T1 Stage Clear Cell Renal Cell Carcinoma: A CT-Based Radiomics Nomogram to Estimate the Risk of Recurrence and Metastasis

Objectives

To develop and validate a radiomics nomogram to improve prediction of recurrence and metastasis risk in T1 stage clear cell renal cell carcinoma (ccRCC).

Methods

This retrospective study recruited 168 consecutive patients (mean age, 53.9 years; range, 28–76 years; 43 women) with T1 ccRCC between January 2012 and June 2019, including 50 aggressive ccRCC based on synchronous metastasis or recurrence after surgery. The patients were divided into two cohorts (training and validation) at a 7:3 ratio. Radiomics features were extracted from contrast enhanced CT images. A radiomics signature was developed based on reproducible features by means of the least absolute shrinkage and selection operator method. Demographics, laboratory variables (including sex, age, Fuhrman grade, hemoglobin, platelet, neutrophils, albumin, and calcium) and CT findings were combined to develop clinical factors model. Integrating radiomics signature and independent clinical factors, a radiomics nomogram was developed. Nomogram performance was determined by calibration, discrimination, and clinical usefulness.

Results

Ten features were used to build radiomics signature, which yielded an area under the curve (AUC) of 0.86 in the training cohort and 0.85 in the validation cohort. By incorporating the sex, maximum diameter, neutrophil count, albumin count, and radiomics score, a radiomics nomogram was developed. Radiomics nomogram (AUC: training, 0.91; validation, 0.92) had higher performance than clinical factors model (AUC: training, 0.86; validation, 0.90) or radiomics signature as a means of identifying patients at high risk for recurrence and metastasis. The radiomics nomogram had higher sensitivity than clinical factors mode (McNemar’s chi-squared = 4.1667, p = 0.04) and a little lower specificity than clinical factors model (McNemar’s chi-squared = 3.2, p = 0.07). The nomogram showed good calibration. Decision curve analysis demonstrated the superiority of the nomogram compared with the clinical factors model in terms of clinical usefulness.

Conclusion

The CT-based radiomics nomogram could help in predicting recurrence and metastasis risk in T1 ccRCC, which might provide assistance for clinicians in tailoring precise therapy.

Retrospective Multicenter Long-Term Follow-up Analysis of Prognostic Risk Factors for Recurrence-Free, Metastasis-Free, Cancer-Specific, and Overall Survival After Curative Nephrectomy in Non-metastatic Renal Cell Carcinoma

We evaluated prognostic risk factors of recurrence-free survival (RFS), metastasis-free survival (MFS), cancer-specific survival (CSS), and overall survival (OS) outcomes in patients with non-metastatic renal cell carcinoma (nmRCC) after curative nephrectomy during long-term follow-up. The medical records of 4,260 patients with nmRCC who underwent curative nephrectomy between 2000 and 2012 from five Korean institutions and follow-up after postoperative 1 month until December 2017 were retrospectively analyzed for RFS, MFS, OS, and CSS. During the median 43.86 months of follow-up, 342 recurrences, 127 metastases, and 361 deaths, including 222 cancer-specific deaths, were reported. In addition to the unreached median survival of RFS and MFS, the median OS and CSS times were 176.75 and 227.47 months, respectively. Multivariable analyses showed that nephrectomy type (laparoscopy vs. open), pathological T stages, and nuclear grade were common significant risk factors for survival, and the baseline ASA, hemoglobin, and pathological N stage were common factors only for RFS, OS, and CSS (p < 0.05). Further, tumor necrosis for MFS; platelet count, extent (partial vs. radical) of surgery, and lymphovascular invasion for RFS; baseline diabetes, hypertension, age, body mass index, extent of surgery, and pathological sarcomatoid differentiation for OS; and baseline diabetes, hypertension, body mass index, and pathological sarcomatoid differentiation for CSS were additionally significant risk factors (p < 0.05). RFS, MFS, OS, and CSS were significantly different depending on the pathological T stages (p < 0.05). In conclusion, this large-numbered, long-term follow-up study revealed significant factors affecting the survival of patients with nephrectomized nmRCC.

The follow-up management of non-metastatic renal cell carcinoma: definition of a surveillance protocol

OBJECTIVE

To define a follow-up protocol based on the University of California Los Angeles Integrated Staging System (UISS) for patients undergoing surgery for N0M0 renal cell carcinoma (RCC).

PATIENTS AND METHODS

The clinical records of patients treated with radical surgery for N0/NXM0 RCC and monitored through periodic follow-up studies (> or =24 months in disease-free patients) were reviewed retrospectively from 1399 patients surgically treated for renal neoplasms between 1983 and 2005. Each case was assigned a UISS risk category; recurrence features, time and site were recorded. In particular, recurrence sites were categorized into local, renal (ipsilateral or contralateral) and distant (single-site or disseminated).

RESULTS

The records were reviewed of 814 patients with a mean follow-up of 75.6 months. UISS risk categories were distributed as follows: high-risk (HR) 17.2%, intermediate-risk (IR) 51.6% and low-risk (LR) 31.2%. Disease-free survival rates at 5 years were 63.9%, 88.3% and 96.5% (log-rank test P < 0.001), respectively. The disease recurred in 193 patients (23.7%), at distant sites (73.0% of recurrences), locally (11.9%), in the contralateral kidney (10.9%) and in the ipsilateral kidney (4.1%). There was a significant correlation between UISS category and risk of distant or local (both P < 0.001) recurrences, whereas there was no correlation of recurrences in the operated kidney (P = 0.372) or contralateral kidney (P = 0.898).

CONCLUSIONS

The prognostic accuracy and applicability of the UISS for distant and local recurrences is confirmed, whereas renal relapses have an independent course. A follow-up scheme tailored to the recurrence patterns observed in each UISS risk group is recommended.

Renal cell carcinoma local recurrences: impact of surgical treatment and concomitant metastasis on survival

OBJECTIVE

To analyse the survival benefit of resecting local recurrence (LR) of renal cell carcinoma (RCC) in the presence and absence of concomitant metastasis.

PATIENTS AND METHODS

From 1989 to 2004 we identified 34 patients with LRs (2.9%) of the 1165 radical nephrectomies performed for T1-4N0M0 disease. Of these, 18 (53%) had no evidence of metastasis (isolated LR incidence, 1.5%) and 16 (47%) had synchronous metastasis. Of the 18 patients with no metastasis, 11 had complete surgical resection (group I) and seven had nonsurgical therapy (group II). Of the 16 patients with synchronous metastasis, five had surgery (group III) and 11 did not (group IV). Survival was projected using the Kaplan-Meier method and log-rank test for each group.

RESULTS

Eight of the 34 patients (24%) were symptomatic. The T stage of the initial nephrectomy was T1a in two cases, T1b in six, T2 in five, T3a in six, T3b in eight, T4 in six and unknown in one; 22 patients (65%) had clear cell histology. There were no significant differences in median time to LR or the LR size among the groups. The median (range) follow-up was 16.9 (0.5-103.6) months. Of the 11 patients in group I, three remain with no evidence of disease, three are alive with metastatic disease, and five died from disease. By contrast, 21 of the 23 patients (91%) in groups II, III and IV died from disease. The overall estimated 1-, 3- and 5-year survivals were 63%, 31% and 18%. The median survival time was 71.4 months for group I, 9.9 for II, 16.3 for III, and 11.8 for IV (P < 0.01) with a 5-year survival of 62% for group I and 0% for groups II, III, and IV.

CONCLUSIONS

LR after radical nephrectomy is rare (2.9%) and has a poor prognosis. The presence of synchronous metastasis and nonoperative therapy are related to these low survival rates. However, if there is no metastatic disease, complete surgical resection of LRs is associated with improved survival.

Multiple primary malignancies in patients with renal cell carcinoma: a national population-based cohort study

OBJECTIVE

To determine the possibly greater occurrence of multiple malignancies in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

In the 7-year period 1987-93, all 1425 patients aged 15-70 years with registered histopathologically verified RCC in Norway were included in the study. All clinical and histopathology reports were checked manually, to verify the registered diagnosis and to ensure that no tumour was a metastasis from another. After this process, 257 patients (287 tumours other than RCC) with multiple primary malignancies were identified. The primary tumours other than RCC were classified as antecedent, synchronous and subsequent. For the subsequently occurring tumours, the expected number of different tumour types was calculated according to age group, gender and observation time.

RESULTS

Of the 1425 patients, 228 (16%) had one, 23 (1.6%) had two, three (0.2%) had three and one (0.07%) had four other primary malignancies. In all, 100 (34.8%) of the other tumours were diagnosed as antecedent, 53 (18.7%) as synchronous and 134 (46.7%) as subsequent to the RCC. Cancer in the prostate, bladder, lung, breast, colon and rectal cancer, malignant melanomas (MM) and non-Hodgkin's lymphomas (NHL) were the most common other malignancies. The observed overall number of subsequent other malignant tumours was 22% higher than the expected number. The observed number of subsequent tumours was significantly higher for bladder cancer, NHL and MM. The estimated 15-year cumulative risk for patients with RCC and no previous or synchronous other malignancy for developing a later second cancer was 26.6% in men, and 15.5% in women (statistically significant, P = 0.04). Patients with antecedent or synchronous other cancer had significantly poorer overall survival than those without.

CONCLUSIONS

Patients with RCC seem to have a significantly higher risk of developing other subsequent primary malignancies. This should be considered during the follow-up of patients with RCC.

Surgical excision of isolated renal-bed recurrence after radical nephrectomy for renal cell carcinoma

OBJECTIVE

To present our results on managing loco-regional recurrence of renal cell carcinoma (RCC) with surgical excision, as local recurrence at the site of a previous nephrectomy is resistant to both systemic therapy and radiotherapy.

PATIENTS AND METHODS

In all, 16 patients were operated on between 1994 and 2003 for local recurrence of RCC. The median (mean, range) age at the time of local recurrence was 57.9 (57.4, 28.9-71.7) years, and the median interval from primary surgery 2.22 (3.88, 0.27-14.46) years. Before surgery eight patients had been given systemic immunotherapy, with no response of their local recurrence.

RESULTS

Two patients were deemed inoperable because of direct invasion of the great vessels and the liver by tumour. The remaining 14 patients had recurrence in residual adrenal tissue (two), para-aortic nodes (three), para-caval nodes (two), retrocaval nodes (one), renal bed (six), liver, spleen and stomach (one each), and diaphragm (two). Although complete macroscopic en-bloc clearance was achieved in these patients, only eight had tumour-free margins on histological examination. The histology was consistent with RCC recurrence in all cases. All of the patients were followed with computed tomography at regular intervals. At a median follow-up of 1.0 (1.65, 0.25-6.5) years, five patients remain disease-free, four have local and distant relapse, and five developed distant metastasis only. The presence of tumour at the resection margin was a significant factor in predicting local and distant disease-free survival (P < 0.05).

CONCLUSIONS

En bloc excision of isolated locally recurrent RCC is possible, and complete surgical extirpation can lead to prolonged disease-free survival.

Re-evaluation of the Tumour-Node-Metastasis staging of locally advanced renal cortical tumours: absolute size (T2) is more significant than renal capsular invasion (T3a)

Authors from Iowa City report on the incidence of RCC; they compared the rate of these tumours at autopsy and felt that the decrease found was a result of better antemortem detection, and an increase with time in the frequency of clinically detected renal cancer. A study from New York attempted to determine whether size, or transcapsular extension irrespective of size, was more likely to produce an adverse outcome. They analysed their database of 717 such tumours between 1988 and 2002, and found that absolute tumour size was the more significant of the two findings.

OBJECTIVE

To determine which factor was more predictive of adverse outcome in our institutional experience with T2N0M0 and T3N0M0 renal cortical tumours (RCTs) treated surgically, as the current Tumour-Node-Metastasis (TNM) staging system for RCTs differentiates between tumours of >7.0 cm but confined to the renal capsule (T2) and tumours that extend through the renal capsule regardless of size (T3a).

MATERIALS AND METHODS

We analysed our institutional database of surgical urological oncology for all patients with T2N0M0 and T3aN0M0 RCT treated with partial or radical nephrectomy from 1988 to 2002. All patients with preoperative metastasis, bilateral or multifocal tumours, nonsporadic disease or benign histology were excluded from analysis. A follow-up of > or = 6 months from the time of surgery was required for inclusion. Primary outcomes included local and distant recurrence, and death.

RESULTS

In all, 717 patients had a partial or radical nephrectomy for RCT during the study period. After exclusion criteria were applied, 21 patients with T2N0M0 and 97 with T3aN0M0 tumours were eligible; the median (mean, range) age was 63 (16.6-88.3) years and follow-up 30.5 (40.8, 6-162) months. The estimated 5-year disease-free survival was 68% and 85% for T2N0M0 and T3aN0M0 RCT, respectively (P = 0.002). The 5-year disease-specific survival was 81% and 94% for the T2N0M0 and T3aN0M0 groups, respectively (P = 0.085).

CONCLUSION

Patients with T3aN0M0 tumours appear to have better disease-free and disease-specific survival than those with T2N0M0 disease, which suggests that tumour invasion through the renal capsule is not as significant as the absolute tumour size.