Laparoscopic ablation therapies or hepatic resection in cirrhotic patients with small hepatocellular carcinoma

Thermal ablation versus liver resection for hepatocellular carcinoma in patients with cirrhosis: a systematic review and meta-analysis of propensity-score matched studies

The outcomes of cirrhotic patients with hepatocellular carcinoma (HCC) after thermal ablation (TA) versus liver resection (LR) are debated. We aimed to compare the overall survival (OS), disease-free survival (DFS), and operative outcomes after TA and LR for HCC in patients with cirrhosis. Until November 15, 2022, we searched PubMed, Embase, and Cochrane databases by using Medical Subject Heading terms and other terms, and used the Newcastle-Ottawa literature evaluation scale to assess the quality of selected studies. OS, DFS, and operative outcomes were extracted and analyzed. The meta-analysis showed that 5 propensity-score matched (PSM) studies including 933 patients (463 TA vs. 470 LR) were included. After analysis, TA and LR had similar results at 1-year OS (odds ratio [OR] 1.68; 95% confidence interval [CI] 1.01-2.78; P = 0.05) and 3-year OS (OR 0.76; 95% CI 0.56-1.04; P = 0.08), whereas LR increased 5-years OS (OR 0.37; 95% CI 0.18-0.74; P = 0.005). In addition to the DFS, the 1-year DFS was significantly higher in patients with LR. However, there were no obvious differences in 3-year and 5-year DFS when comparing TA and LR. The length of operative time and hospital stay were longer in the LR group. Besides, the LR group had significantly higher rate of perioperative blood transfusions and major complications. Our research proved that LR took advantage of OS and DFS for HCC patients with cirrhosis. Additional well-designed randomized controlled trials are needed.

Laparoscopic Hepatic Resection Versus Laparoscopic Radiofrequency Ablation for Subcapsular Hepatocellular Carcinomas Smaller Than 3 cm: Analysis of Treatment Outcomes Using Propensity Score Matching

Objective

To compare the therapeutic outcomes of laparoscopic hepatic resection (LHR) and laparoscopic radiofrequency ablation (LRFA) for single subcapsular hepatocellular carcinoma (HCC).

Materials and Methods

We screened 244 consecutive patients who had received either LHR or LRFA between January 2014 and December 2016. The feasibility of LRFA in patients who underwent LHR was retrospectively assessed by two interventional radiologists. Finally, 60 LRFA-feasible patients who had received LHR and 29 patients who had received LRFA as the first treatment for a solitary subcapsular HCC between 1 cm and 3 cm were finally included. We compared the therapeutic outcomes, including local tumor progression (LTP), recurrence-free survival (RFS), and overall survival (OS) between the two groups before and after propensity score (PS) matching. Multivariable Cox proportional hazard regression was also used to evaluate the difference in OS and RFS between the two groups for all 89 patients.

Results

PS matching yielded 23 patients in each group. The cumulative LTP and OS rates were not significantly different between the LHR and LRFA groups after PS matching (p = 0.900 and 0.003, respectively). The 5-year LTP rates were 4.6% and 4.4%, respectively, and OS rates were 100% and 90.7%, respectively. The RFS rate was higher in LHR group without statistical significance (p = 0.070), with 5-year rates of 78.3% and 45.3%, respectively. OS was not significantly different between the LHR (reference) and LRFA groups in multivariable analyses, with a hazard ratio (HR) of 1.33 (95% confidence interval, 0.12–1.54) (p = 0.818). RFS was higher in LHR (reference) than in LRFA without statistical significance in multivariable analysis, with an HR of 2.01 (0.87–4.66) (p = 0.102).

Conclusion

There was no significant difference in therapeutic outcomes between LHR and LRFA for single subcapsular HCCs measuring 1–3 cm. The difference in RFS should be further evaluated in a larger study.

Efficacy and safety of various primary treatment strategies for very early and early hepatocellular carcinoma: a network meta-analysis

BACKGROUND

Several treatments are available for treatment of early and very early-stage Hepatocellular Carcinoma, also known as small Hepatocellular Carcinoma (SHCC). However, there is no consensus with regards to the efficacies of these methods. We aimed at identifying the most effective initial treatment strategy for SHCC through Bayesian network meta-analyses.

METHODS

Studies published between January, 2010, and February, 2021 were searched in EMBASE, Cochrane Library, PubMed and Web of science databases, and conference proceedings for trials. The included studies reported the survival outcomes of very early and early Hepatocellular Carcinoma patients subjected to radiofrequency ablation (RFA), microwave ablation (MWA), surgical resection (SR), transarterial chemoembolization (TACE), percutaneous ethanol injection (PEI), minimally invasive liver surgery (MIS), stereotactic body radiotherapy (SBRT) and cryoablation (CA). Then, data were extracted from studies that met the inclusion criteria. Patient survival data were retrieved from the published Kaplan-Meier curves and pooled. A Bayesian random-effects model was used to combine direct and indirect evidence.

RESULTS

A total of 2058 articles were retrieved and screened, from which 45 studies assessing the efficacies of 8 different treatments in 11,364 patients were selected. The included studies had high methodological quality. Recurrence free survival* (progression/recurrence/relapse/disease/tumor-free survival were combined and redefined as RFS*) and overall survival (OS) outcomes were highest in MIS-treated patients (HR 0·57, 95% confidence intervals [CI] 0·38-0·85; HR 0.48,95% CI 0.36-0.64, respectively), followed by SR-treated patients (HR 0.60, 95% CI 0.50-0.74; HR 0.62, 95% CI 0.55-0.72, respectively). TACE was highly efficacious (58.9%) at decreasing the rates of major complications. Similar findings were obtained through sensitivity analysis, and in most of the prognostic subgroups.

CONCLUSIONS

MIS and SR exhibited the highest clinical efficacies, however, they were associated with higher rates of complications. Ablation is effective in small tumors, whereas SBRT is a relatively promising treatment option for SHCC. More well-designed, large-scale randomized controlled trials should be performed to validate our findings.

Current status of radical laparoscopy for treating hepatocellular carcinoma with portal hypertension

The laparoscopic technique is clinically effective in treating hepatocellular carcinoma (HCC) with portal hypertension (PHT). However, existing studies lack systematic arrangement and induction. Here, we review the latest research advancement in laparoscopic technique for treatment of HCC with PHT, based on published literature and our single-institution experience. Our single-center experience reveals no statistical difference in both short- and long-term prognosis of HCC patients after laparoscopic liver resection (LLR), regardless of whether they suffer from PHT, which is consistent with previous studies on the use of LLR for HCC with PHT. Retrieval outcomes indicate existence of short- and long-term prognostic superiority, following laparoscopic treatment, relative to non-laparoscopic treatment. Besides that, LLR offers long-term prognostic advantage compared to laparoscopic radiofrequency ablation. In addition, we review the previous literature and propose corresponding perspectives on the therapy of hypersplenism, the utilization of Pringle maneuver, and the adoption of anatomical hepatectomy during radical laparoscopic treatment. HCC with PHT is not the "forbidden zone" of radical laparoscopic treatment. However, patients’ preoperative liver function should be adequately estimated.

Micronvasive behaviour of single small hepatocellular carcinoma: which treatment?

BACKGROUND

Microinvasion (MI), defined as infiltration of the portal or hepatic vein or bile duct and intrahepatic metastasis are accurate indicators of a poor prognosis for mall hepatocellular carcinomas (HCC). A previous study showed that intraoperative ultrasound (IOUS) definition of MI-HCC had a high concordance with histological findings. Aim of this study is to evaluate overall survival and recurrence patterns of patients with MI-HCC submitted to hepatic resection (HR) or laparoscopic ablation therapies (LAT).

METHODS

A total of 171 consecutive patients (78 h; 93 LAT) with single, small HCC (< 3 cm) with a MI pattern at IOUS examination were compared analyzing overall survival and recurrence patterns using univariate and multivariate analysis and weighting by propensity score.

RESULTS

Overall recurrences were similar in the 2 groups (HR: 51 patients (65%); LAT: 66 patients (71%)). The rate of local tumor progression in the HR group was very low (5 pts; 6%) in comparison to LAT group (22 pts; 24%; p = 0.002). The overall survival curves of HR are significantly better than that of the LAT group (p = 0.0039). On the propensity score Cox model, overall mortality was predicted by the surgical treatment with a Hazard ratio 1.68 (1.08-2.623) (p = 0.022).

CONCLUSIONS

If technically feasible and in patients fit for surgery, HR with an adequate tumor margin should be preferred to LAT in patients with MI-HCC at IOUS evaluation, to eradicate MI features near the main nodule, which are relatively frequent even in small HCC (< 3 cm).

Percutaneous radiofrequency ablation is superior to hepatic resection in patients with small hepatocellular carcinoma

BACKGROUND

It is not known whether percutaneous radiofrequency ablation (PRFA) has the same treatment efficacy and fewer complications than laparoscopic resection in patients with small centrally located hepatocellular carcinoma (HCC).

AIM

To compare the effectiveness of PRFA with classical laparoscopic resection in patients with small HCC and document the safety parameters.

METHODS

In this retrospective study, 85 patients treated with hepatic resection (HR) and 90 PRFA-treated patients were enrolled in our hospital from July 2016 to July 2019. Treatment outcomes, including major complications and survival data, were evaluated.

RESULTS

The results showed that minor differences existed in the baseline characteristics between the patients in the two groups. PRFA significantly increased cumulative recurrence-free survival (hazard ratio 1.048, 95%CI: 0.265–3.268) and overall survival (hazard ratio 0.126, 95%CI: 0.025–0.973); PRFA had a lower rate of major complications than HR (7.78% vs 20.0%, P < 0.05), and hospital stay was shorter in the PRFA group than in the HR group (7.8 ± 0.2 d vs 9.5 ± 0.3 d, P < 0.001).

CONCLUSION

Based on the data obtained, we conclude that PRFA was superior to HR and may reduce complications and hospital stay in patients with small HCC.

Comparative Effectiveness of Radiofrequency Ablation vs. Surgical Resection for Patients With Solitary Hepatocellular Carcinoma Smaller Than 5 cm

Background: This study aims to compare survival outcome after receiving radiofrequency ablation (RFA) and surgical resection (SR) for solitary hepatocellular carcinoma (HCC) with size large as 5 cm.

Methods: The SEER database was queried for patients with HCC tumors who were treated with RFA or SR between 2004 and 2015. Univariate and multivariate Cox analysis was used to assess the influence of potential variables on the patients' outcome. Additionally, propensity score matching (PSM) and multiple imputations (MI) were used as sensitivity analyses.

Results: Of 1,985 cases, 934 patients received RFA treatment, while the rest underwent surgical resection. The patients in the RFA group had poorer overall survival (OS) and cancer-specific survival (CSS) than those in the SR group regardless of the tumor size before matching and MI. By using PSM analysis at a 1:1 ratio, 1,302 cases were paired and we have found that SR had a positive impact on OS and CSS of patients with tumors measuring from 3.1 to 5 cm. However, when the tumor size was <3 cm, patients undergoing SR had similar survival benefit with those after RFA. The above results were confirmed after performing PSM analysis at a 1:2 and 1:3 ratio.

Conclusion: By applying several effective sensitivity analyses, we demonstrated that OS and CSS were similar between the patients with tumors smaller than 3 cm receiving RFA and SR. But SR may be a superior treatment option with better long-term outcome than RFA in patients with tumor measuring 3.1–5 cm.

Percutaneous thermal ablation of subcapsular hepatocellular carcinomas: influence of tumor-surface contact and protrusion on therapeutic efficacy and safety

PURPOSE

To evaluate therapeutic efficacy and complication of percutaneous thermal ablation of subcapsular hepatocellular carcinomas (HCCs), and how these may be influenced by the degree of tumor to liver surface contact and tumor protrusion from liver surface.

MATERIALS AND METHODS

Our retrospective study was approved by the Institutional Review Board. Between January 2006 and December 2013, 290 patients (82 women, 208 men; mean age, 64.5 years; range, 33-89 years) with 474 subcapsular (within 1 cm to the liver surface) HCCs (mean size, 23.7 mm; range, 6-71 mm) underwent percutaneous thermal ablation. The HCCs were divided into surface contact group (n = 243) and non-surface contact group (n = 231). The former was further subdivided into exophytic and non-exophytic HCCs. Technical success, primary technique efficacy, local tumor progression (LTP), and secondary technique efficacy rates were analyzed and compared by the chi-square test or Fisher exact test. Prognostic factors for LTP and secondary technique efficacy were assessed using the Cox regression model. Major complications were also assessed.

RESULTS

With median follow-up of 15 months (range, 1-87 months), technical success and primary technique efficacy were 98.7% and 95.7% % in the non-surface contact group; 96.4% and 94.0% in the non-exophytic group; and 100% and 94.7% in the exophytic group (p > 0.05). Tumor size > 3 cm was a significant predictor for LTP, but not for secondary efficacy. Overall major complication rate was 3.8% (24/624) and was not different among the three groups.

CONCLUSION

Subcapsular HCCs can be effectively treated with thermal ablation techniques. Degree of tumor-surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness.

KEY POINTS

• Subcapsular HCCs can be effectively treated with thermal therapy when proper image-guided technique and assistive techniques are applied. • Degree of tumor surface contact including moderate protrusion does not appear to limit feasibility or procedure effectiveness. • Major complications after percutaneous thermal ablation of subcapsular HCCs such as tumor seeding can be minimized by avoiding breach of the tumor capsule exposed to the peritoneal surface and use of tract ablation.

Preoperative MRI features and clinical laboratory indicators for predicting the early therapeutic response of hepatocellular carcinoma to transcatheter arterial chemoembolization combined with High-intensity focused ultrasound treatment

OBJECTIVES

To evaluate the value of preoperative MRI features and laboratory indicators in predicting the early response of hepatocellular carcinoma (HCC) to transcatheter arterial chemoembolization (TACE) combined with high-intensity focused ultrasound (HIFU) treatment and to establish a preoperative prediction model.

METHODS

A total of 188 patients with 223 tumors who underwent TACE/HIFU treatment from January 2011 to June 2017 were included. Tumors were divided into three groups (< 2 cm, 2 - 5 cm,> 5 cm) and classified as non-complete response (NCR) and complete response (CR) cohorts according to the Response Evaluation Criteria in Cancer of the Liver (RECICL) 2015 revised version. Univariate analysis and multivariate logistic regression analysis were used to determine independent predictors, and receiver operating characteristic (ROC) curve analysis was performed to assess the diagnostic power of each predictor. The prediction model was derived on the β coefficient of the multivariate regression analysis of the predictors.

RESULTS

Irregular margins in the 2 - 5 cm group were closely related to early NCR. Irregular margins, arterial peritumoral enhancement and abnormal alpha-fetoprotein (AFP) were independent predictors of early NCR in the > 5 cm group. The prediction model of this group suggests that irregular margins combined with arterial peritumoral enhancement and abnormal AFP combined with irregular margins and arterial peritumoral enhancement predict an increased risk of early NCR.

CONCLUSION

Irregular margins of 2 - 5 cm tumors and irregular margins, arterial peritumoral enhancement, and abnormal AFP of tumors > 5 cm can be applied to predict the early response of HCC to TACE/HIFU treatment.

ADVANCES IN KNOWLEDGE

TACE combined with HIFU treatment may be able to significantly improve survival in patients with advanced HCC. Conventional MRI features and laboratory indicators are readily available without complex post-processing. It is feasible to predict the response of HCC after TACE/HIFU treatment based on preoperative conventional MRI features and laboratory indicators, the combination of multiple features predicts high-risk of non-complete response.

Intention-to-treat analysis of liver transplantation, resection and thermal ablation for hepatocellular carcinoma in a single centre

BACKGROUND

potentially curative treatment options for hepatocellular carcinoma (HCC) include liver transplantation (LT), liver resection (LR) and thermal ablation (TA). Long term intent-to-treat (ITT) analysis from a single-centre using all three modalities contemporaneously has not been published.

METHODS

An ITT analysis was undertaken of all patients with HCC listed for LT, or have undergone LR or TA.

RESULTS

444 patients were identified; 145 were listed for LT (121 underwent LT), 190 underwent LR and 109 underwent TA. One and 3-year overall survival (OS) was similar among LT, LR and TA (88/77%, 88/64% and 95/72%) whereas 5-year OS was higher following LT than LR or TA (73% vs. 54% vs. 49%). Disease-free survival at 1- and 5-years was higher for LT (97% and 84%) than LR (66% and 35%) or TA (73%, and 19%).

CONCLUSION

LT offered the lowest rate of cancer recurrence and highest chance of long-term survival. Differences in outcome likely reflect a combination of cancer-related factors (AFP, micro- and macrovascular invasion), patient-related factors (performance status, co-morbidities and psychosocial issues) and treatment type. Two thirds of patients treated by LR and three quarters treated by TA had HCC recurrence by 5 years, reinforcing the need for close long-term surveillance.

Open Liver Resection, Laparoscopic Liver Resection, and Percutaneous Thermal Ablation for Patients with Solitary Small Hepatocellular Carcinoma (≤30 mm): Review of the Literature and Proposal for a Therapeutic Strategy

BACKGROUND

Patients with a single hepatocellular carcinoma (HCC) ≤3 cm and preserved liver function have the highest likelihood to be cured if treated. The most adequate treatment methods are yet a matter that is debated.

METHODS

We reviewed the literature about open anatomic resection (AR), laparoscopic liver resection (LLR), and percutaneous thermal ablation (PTA).

RESULTS

PTA is effective as resection for HCC < 2 cm, when they are neither subcapsular nor perivascular. PTA in HCC of 2-3 cm is under evaluation. AR with the removal of the tumor-bearing portal territory is recommended for HCC > 2 cm, except for subcapsular ones. In comparison with open surgery, LRR has better short-term outcomes and non-inferior long-term outcomes. LLR is standardized for superficial limited resections and for left-sided AR.

CONCLUSIONS

According to the available evidences, the following therapeutic proposal can be advanced. Laparoscopic limited resection is the standard for any subcapsular HCC. PTA is the first-line treatment for deep-located HCC < 2 cm, except for those in contact with Glissonean pedicles. Laparoscopic AR is the standard for deep-located HCC of 2-3 cm of the left liver, while open AR is the standard for deep-located HCC of 2-3 cm in the right liver. HCC in contact with Glissonean pedicles should be scheduled for resection (open or laparoscopic) independent of their size. Liver transplantation is reserved to otherwise untreatable patients or as a salvage procedure at recurrence.

Surgical Resection vs. Ablative Therapies Through a Laparoscopic Approach for Hepatocellular Carcinoma: a Comparative Study

BACKGROUND

When compatible with the liver functional reserve, laparoscopic hepatic resection remains the treatment of choice for hepatocellular carcinoma while laparoscopic ablation therapies appear as a promising less invasive alternative. The aim of the study is to compare two homogeneous groups of patients submitted to either hepatic resection or thermoablation for the treatment of single hepatocellular carcinoma (≤ 3 cm).

METHODS

We enrolled 264 cirrhotic patients out of 905 cases consecutively evaluated for hepatocellular carcinoma. We performed 59 hepatic resections and 205 thermoablations through a laparoscopic approach, and they were then followed for similar follow-up (41.7 ± 31.5 months for laparoscopic hepatic resection vs. 38.7±32.3 for laparoscopic ablation therapy). Outcomes included short- and long-term morbidities, tumoral recurrence, and overall survival.

RESULTS

Short-term morbidity was significantly higher in the resection group (but the two groups had similar rates for severe complications) while, during follow-up, recurrence was more frequent in patients treated with thermoablation, with a clear disadvantage in terms of survival. At multivariate analysis, only the type of surgical treatment was an independent predictor of disease recurrence, while plasmatic alpha-fetoprotein and Hb values, model for end-stage liver disease score, time to recurrence, and the type of surgical treatment were independent predictors of overall survival.

CONCLUSION

Our data ultimately support some therapeutic advantages for hepatic resection in patients with a single nodule and preserved liver function. However, thermoablation is an adequate alternative in patients with nodules that would require complex surgical resections or imply a poor prognosis that might therefore better tolerate a less invasive procedure.

Nomograms to Predict the Disease-free Survival and Overall Survival after Radiofrequency Ablation for Hepatocellular Carcinoma

Objective The purpose of this study was to construct nomograms for the disease-free survival (DFS) and overall survival (OS) of post-radiofrequency ablation (RFA) patients with hepatocellular carcinoma (HCC). Furthermore, we compared the prognostic predictive ability of these nomograms for estimating per-patient outcomes with that of traditional staging systems. Methods We retrospectively enrolled 298 patients in the training set and 272 patients in the validation set who underwent RFA for HCC. The nomograms for the DFS and OS were constructed from the training set using the multivariate Cox proportional hazards model. The discriminatory accuracy of the models was compared with traditional staging systems by analyzing the Harrell's C-index. Results The DFS nomogram was developed based on the tumor size, tumor number, aspartate aminotransferase (AST), albumin, age, and α-fetoprotein. The OS nomogram was developed based on the tumor size, the model for end-stage liver disease, AST, and albumin. Our DFS and OS nomograms had good calibration and discriminatory abilities in the training set, with C-indexes of 0.640 and 0.692, respectively, that were greater than those of traditional staging systems. The C-indexes of our DFS and OS nomograms were also greater than those of traditional staging systems in the validation set, with C-indexes of 0.614 and 0.657, respectively. RFA patients were stratified into low- and high-risk groups based on the median nomogram scores. High-risk patients receiving surgical resection (SR) were associated with a better DFS and OS than those undergoing RFA. However, the DFS and OS were similar between the low-risk RFA and SR groups. Conclusion We constructed reliable and useful nomograms that accurately predict the DFS and OS after RFA for early-stage HCC patients. These graphical tools are easy to use and will assist physicians during the therapeutic decision-making process.

Effect of Age (over 75 Years) on Postoperative Complications and Survival in Patients Undergoing Hepatic Resection for Hepatocellular Carcinoma

BACKGROUND

Thanks to technical advancement in surgery for hepatocellular carcinoma (HCC), hepatic resection (HR) for elderly HCC patients has become safer. However, elderly patients may have shorter long-term survival after surgery if compared with younger patients because of their expected life span. The aim of the present study was to evaluate clinical outcomes and safety after HR in HCC patients aged >75 years (older) compared with HCC patients aged <75 years (younger).

METHOD

One hundred sixty-eight patients who underwent HR for HCC from 1998 to 2015 in our Center were analyzed using a prospective database. Complications, disease-free survival rates, and cumulative survival rates were compared between the two groups.

RESULTS

During the immediate postoperative period, no differences were found about liver-related complications, hospital stay and 90-day mortality. However, older patients had more complications in class II or higher (Clavien classification) (p = 0.017). Although disease-free survival in both groups was similar (p = 0.099), overall survival was worse in the elderly group (p = 0.024). On multivariate analysis, only age ≥75 years was significantly related to overall survival.

CONCLUSION

If elderly patients with liver cirrhosis and HCC are appropriately selected and evaluated, they might have favorable prognoses after HR.

Comparative effectiveness of first-line radiofrequency ablation versus surgical resection and transplantation for patients with early hepatocellular carcinoma

BACKGROUND

Significant controversy exists as to which treatment modality is most effective for small, solitary hepatocellular carcinomas (HCCs): radiofrequency ablation (RFA), surgical resection (RXN), or transplantation (TXP). Size cutoff values ranging from 20 to 50 mm have been proposed to achieve complete ablation. The current study compares outcomes between RFA, RXN, and TXP as first-line therapy for patients with HCC tumors measuring as large as 50 mm.

METHODS

The Surveillance, Epidemiology, and End Results database was queried for patients with HCC tumors measuring up to 50 mm who were treated with RFA, RXN, or TXP between 2004 and 2013. Overall survival (OS) and disease-specific survival (DSS) were examined in patients with tumors measuring ≤20 mm, 21 to 30 mm, or 31 to 50 mm. The impact of an increase in tumor size of only 5 mm beyond 30 mm was evaluated by also examining outcomes in patients with tumors measuring 31 to 35 mm.

RESULTS

Of 1894 cases, patients with HCC tumors measuring ≤20 mm and 21 to 30 mm demonstrated no difference in OS or DSS regardless of whether RFA and RXN was used. RFA was associated with a worse OS and DSS than TXP, whereas there was no difference in OS observed between RXN and TXP. In patients with tumors measuring 31 to 50 mm, OS and DSS were worse with RFA compared with RXN or TXP. Most important, the inferior DSS and OS noted with RFA were observed with only a 5-mm increase in tumors measuring >30 mm.

CONCLUSIONS

Although RFA frequently is used as first-line treatment of HCC tumors measuring as large as 50 mm, it is associated with worse results than RXN or TXP for tumors measuring >30 mm. To the best of the authors' knowledge, the results of the current study are the first to demonstrate that although RFA is an appropriate option for patients with HCC tumors measuring ≤30 mm, its use for tumors even slightly larger than 30 mm is associated with inferior outcomes. Cancer 2017;123:1817-1827. © 2017 American Cancer Society.