Accelerated radiotherapy for T1, 2 glottic carcinoma: analysis of results with KI-67 index

Prediction of the Ki-67 expression level in head and neck squamous cell carcinoma with machine learning-based multiparametric MRI radiomics: a multicenter study

BACKGROUND

This study aimed to develop and validate a machine learning (ML)-based fusion model to preoperatively predict Ki-67 expression levels in patients with head and neck squamous cell carcinoma (HNSCC) using multiparametric magnetic resonance imaging (MRI).

METHODS

A total of 351 patients with pathologically proven HNSCC from two medical centers were retrospectively enrolled in the study and divided into training (n = 196), internal validation (n = 84), and external validation (n = 71) cohorts. Radiomics features were extracted from T2-weighted images and contrast-enhanced T1-weighted images and screened. Seven ML classifiers, including k-nearest neighbors (KNN), support vector machine (SVM), logistic regression (LR), random forest (RF), linear discriminant analysis (LDA), naive Bayes (NB), and eXtreme Gradient Boosting (XGBoost) were trained. The best classifier was used to calculate radiomics (Rad)-scores and combine clinical factors to construct a fusion model. Performance was evaluated based on calibration, discrimination, reclassification, and clinical utility.

RESULTS

Thirteen features combining multiparametric MRI were finally selected. The SVM classifier showed the best performance, with the highest average area under the curve (AUC) of 0.851 in the validation cohorts. The fusion model incorporating SVM-based Rad-scores with clinical T stage and MR-reported lymph node status achieved encouraging predictive performance in the training (AUC = 0.916), internal validation (AUC = 0.903), and external validation (AUC = 0.885) cohorts. Furthermore, the fusion model showed better clinical benefit and higher classification accuracy than the clinical model.

CONCLUSIONS

The ML-based fusion model based on multiparametric MRI exhibited promise for predicting Ki-67 expression levels in HNSCC patients, which might be helpful for prognosis evaluation and clinical decision-making.

Biomarkers of laryngeal squamous cell carcinoma: a review

Laryngeal carcinoma is the second common malignancy of the upper aerodigestive tract after lung cancer; in most cases is a squamous cell carcinoma, whose risk factors include tobacco smoking and alcohol consumption. Despite therapeutic progress, the five-year overall survival rate for this malignancy has remained nearly 50% and many patients already present metastasis at the time of diagnosis. To date, there are no tools that predict the evolution of laryngeal carcinoma: in this light, during the last years, many studies were planned with the aim to investigate the role played by different biomarkers expressed by larynx cancer, which can help make an early diagnosis, predict disease evolution and direct therapeutic choice. This review aims to summarize these markers and correlating them with disease evolution.

Biological tumor markers associated with local control after primary radiotherapy in laryngeal cancer: A systematic review

BACKGROUND

The choice of treatment in laryngeal cancer is mainly based on tumor stage, post-treatment morbidity and quality of life. Biological tumor markers might also be of potential clinical relevance.

OBJECTIVE OF THE REVIEW

The aim was to systematically review the value of published biological tumor markers to predict local control in laryngeal cancer patients treated with definitive radiotherapy.

TYPE OF REVIEW

Systematic review.

SEARCH STRATEGY

PubMed, Embase, Cochrane Library.

EVALUATION METHOD

A literature search was performed using multiple terms for laryngeal cancer, radiotherapy, biological markers, detection methods and local control or survival. Studies regarding the relation between biological tumor markers and local control or survival in laryngeal cancer patients primarily treated with radiotherapy were included. Markers were clustered on biological function. Quality of all studies was assessed. Study selection, data extraction and quality assessment was performed by two independent reviewers.

RESULTS

A total of 52 studies out of 618 manuscripts, concerning 118 markers, were included. EGFR and P53 showed consistent evidence for not being predictive of local control after primary radiotherapy, whereas proliferation markers (ie high Ki-67 expression) showed some, but no consistent, evidence for being predictive of better local control. Other clusters of markers (markers involved in angiogenesis and hypoxia, apoptosis markers, cell cycle, COX-2 and DNA characteristics) showed no consistent evidence towards being predictors of local control after primary radiotherapy.

CONCLUSIONS

Cell proliferation could be of potential interest for predicting local control after primary radiotherapy in laryngeal cancer patients, whereas EGFR and p53 are not predictive in contrast to some previous analyses. Large diversity in research methods is found between studies, which results in contradictory outcomes. Future studies need to be more standardised and well described according to the REMARK criteria in order to have better insight into which biomarkers can be used as predictors of local control after primary radiotherapy.

Laser Microsurgery Versus Radiotherapy Versus Open Partial Laryngectomy for T2 Laryngeal Carcinoma: A Systematic Review of Oncological Outcomes

INTRODUCTION

The aim of the current systematic review is to update the pooled survival outcome of patients with T2 glottic carcinoma treated with either laser surgery (CO₂ transoral laser microsurgery [CO₂ TOLMS]), radiotherapy (RT), or open partial laryngectomy (OPL).

METHODS

A systematic search was performed using the MEDLINE database, Scopus, and Google scholar. The inclusion criteria were studies of patients with T2N0 glottic tumor, treated with either primary CO₂ TOLMS, definitive curative RT, or primary OPL, and with reported oncological outcome at 5 years calculated with a Kaplan-Meier or Cox regression method.

RESULTS

The results of the current review show that local control (LC) is higher with OPL 94.4%, while there are no differences in LC at 5-year posttreatment for patients treated with RT, compared to those treated with CO₂ TOLMS (respectively, 75.6% and 75.4%). Primary treatment with OPL and CO₂ TOLMS results in higher laryngeal preservation than primary treatment with RT (respectively 95.8%, 86.9%, and 82.4%).

CONCLUSION

First-line treatment with OPL and CO₂ TOLMS should be encouraged in selected T2 patients, because it results in higher laryngeal preservation and similar LC compared to primary treatment with RT. The involvement of the anterior commissure in the craniocaudal plane and T2b impaired vocal cord mobility have a poorer prognosis and LC compared to patients with T2a tumors for both CO₂ TOLMS and RT.

Standardised Ki-67 proliferation index assessment in early-stage laryngeal squamous cell carcinoma in relation to local control and survival after primary radiotherapy

Objectives

Ambiguous results have been reported on the predictive value of the Ki‐67 proliferation index (Ki‐67 PI) regarding local control (LC) and survival after primary radiotherapy (RT) in early‐stage laryngeal squamous cell cancer (LSCC). Small study size, heterogenic inclusion, variations in immunostaining and cut‐off values are attributing factors. Our aim was to elucidate the predictive value of the Ki‐67 PI for LC and disease‐specific survival (DSS) using a well‐defined series of T1‐T2 LSCC, standardised automatic immunostaining and digital image analysis (DIA).

Methods

A consecutive and well‐defined cohort of 208 patients with T1‐T2 LSCC treated with primary RT was selected. The Ki‐67 PI was determined using DIA. Mann‐Whitney U‐tests, logistic and Cox regression analyses were performed to assess associations between Ki‐67 PI, clinicopathological variables, LC and DSS.

Results

In multivariate Cox regression analysis, poor tumour differentiation (HR 2.20; 95% CI 1.06‐4.59, P = .04) and alcohol use (HR 2.84, 95% CI 1.20‐6.71; P = .02) were independent predictors for LC. Lymph node positivity was an independent predictor for DSS (HR 3.16, 95% CI 1.16‐8.64; P = .03). Ki‐67 PI was not associated with LC (HR 1.59; 95% CI 0.89‐2.81; P = .11) or DSS (HR 0.98; 95% CI 0.57‐1.66; P = .97). In addition, continuous Ki‐67 PI was not associated with LC (HR 2.03; 95% CI 0.37‐11.14, P = .42) or DSS (HR 0.62; 95% CI 0.05‐8.28; P = .72).

Conclusion

The Ki‐67 PI was not found to be a predictor for LC or DSS and therefore should not be incorporated in treatment‐related decision‐making for LSCC.

Survival and Prognostic Factors for Outcome after Radiotherapy for T2 Glottic Carcinoma

Background: Local recurrence after radiotherapy for T2 glottic carcinoma remains an issue and identifying patients at risk for relapse is, therefore, important. This study aimed to assess the oncological outcomes and prognostic factors in a consecutive series of patients treated with radiotherapy for T2N0 glottic carcinoma. Methods: Patients with T2N0 glottic carcinoma treated with radiotherapy were included in this retrospective study. Five- and ten-year local control (LC), overall survival (OS), disease-specific survival (DSS), and laryngeal preservation (LP) rates were calculated with the Kaplan–Meier method. The impact of prognostic variables was evaluated with the log-rank test. Results: Ninety-four patients were included for analysis. LC, OS, DSS, and LP rates were 70.5, 63.7, 86.0, and 74.7%, respectively at five years and 65.8, 41.0, 75.6, and 72.4% at 10 years. In total, 46 scans were included in the analyses. Vertical involvement of the anterior commissure on imaging showed a significant impact on LC. Conclusions: In accordance with previously described surgical risk factors, we identified vertical involvement of the anterior commissure on imaging as a prognostic factor for radiation failure.

Hyperfractionated Radiotherapy for T2N0 Glottic Carcinoma: A Retrospective Analysis at 10 Years Follow-up in a Series of 60 Consecutive Patients

Aims and background

To report results of hyperfractionated radiotherapy for T2N0 glottic carcinoma at a single institution after extended follow-up.

Methods

Between 1980 and 1988 at Varese University Hospital, 60 consecutive patients with T2N0 glottic carcinoma received exclusive radiotherapy consisting of 1.5 Gy/fraction twice a day. Treatment gaps during the radiotherapy course were allowed according to individual tolerance. This policy resulted in a wide range of elapsed treatment time: median, 5.7 weeks; range, 3.7-8.9. Median follow-up is 9.8 years.

Results

As a result of dose/time distribution, 16, 20 and 24 patients received an average weekly dose rate of <10 Gy/week, equal to 10 Gy/week or >10 Gy/week, respectively. Mean total dose for each group was 62.8 Gy, 63.7 Gy and 63.8 Gy, respectively. Five-year local-regional control was 69 ± 6% (95% Cl); ultimate local-regional control, including salvage surgery, was 78 ± 5%. All failures were at the primary site, and no patient developed neck recurrence as first site of failure. The actuarial incidence of grade 2-3 late reactions at 5 years was 42 ± 6%. Most late toxicity events were grade 2: only 2 patients developed grade 3 reactions and none grade 4. None of the several clinical and treatment-related variables showed any statistically significant impact on local-regional control or late toxicity at univariate and multivariate analysis. In particular, 3-year local-regional control rates were 73 ± 11%, 84 ± 8% and 69 ± 10% for an average weekly dose rate of <10 Gy/week, equal to 10 Gy/week and >10 Gy/week, respectively (not significantly different).

Conclusions

At a very long follow-up, the hyperfractionated regimen tested in the study was shown to be effective and devoid of major complications, provided individual patient acute tolerance is carefully taken into account. Also, time factor did not affect outcome in this series.

Transoral laser microsurgery versus radiotherapy for T2 glottic squamous cell carcinoma: a systematic review of local control outcomes

BACKGROUND

Systematic reviews comparing treatment of early glottic cancer with transoral surgery or radiotherapy demonstrate similar oncological outcomes. Most studies of 'early-stage' laryngeal cancer include Tis, T1a, T1b and T2 cases. The data are dominated by patients with T1 and Tis tumours, although extrapolating these results and applying them for T2 cases may be inappropriate. No previous systematic reviews have focused on T2 cancers as a separate group.

OBJECTIVE OF REVIEW

This review compares local control outcomes for T2 glottic squamous cell carcinoma, treated with transoral microsurgery or external beam radiotherapy.

TYPE OF REVIEW

This is a systematic review of case series and comparison studies, focusing on oncological outcomes.

SEARCH STRATEGY

Independent searches of MEDLINE, EMBASE and the Cochrane Database were conducted by two authors, using the search terms: laryngeal/glottic/vocal cord combined with carcinoma/cancer/tumour and laser/microsurgery or radiotherapy. Studies of adult patients treated for primary T2N0 glottic squamous cell carcinoma (SCC) with laser surgery or curative radiotherapy were included.

EVALUATION METHOD

Full text of studies satisfying the inclusion criteria were reviewed with extraction of local control and survival data and laryngeal preservation rates. The primary endpoint is local control at 5 years.

RESULTS

Initial searches identified 3252 studies. Following full-text review of 183 papers, 59 studies met the inclusion criteria, all level IV evidence. A total of 48 studies specified 5-year local control for 1156 patients treated with transoral laser surgery and 3191 patients treated with radiotherapy. Weighted averages of local control at 5 years demonstrated similar results: 75.81% for radiotherapy versus 77.26% for transoral laser surgery.

CONCLUSIONS

The results of this review indicate no difference in 5-year local control between radiotherapy and transoral surgery for T2 glottic SCC. The data demonstrated higher rates of local failure for T2b compared with T2a cases, although outcomes were similar between laser excision and radiotherapy for each substage. Further research focusing upon functional outcomes for T2 glottic tumours is imperative to guide decision-making, ideally with subgroup analysis of T2a and T2b cases.

The clinical relevance of Ki-67 expression in laryngeal squamous cell carcinoma

The aim of this study was to determine the prognostic value of Ki-67 immunostaining in patients affected by laryngeal squamous cell carcinoma. A systematic review was carried out in a tertiary university referral center. An appropriate string was run on PubMed to retrieve articles dealing with Ki-67 immunohistochemical staining and laryngeal squamous cell carcinoma. A double cross-check was performed on citations and full-text articles by two investigators independently to review all manuscripts and perform a comprehensive quality assessment. Of 85 abstracts identified, 18 articles were included. These studies reported on 1,342 patients with histological confirmed diagnosis of laryngeal squamous cell carcinoma. Most studies showed a statistical association between Ki-67 immunohistochemical expression and at least one of the clinical and histopathological parameters considered by the authors. Overall the studies analyzed suggested that the tumoral proliferative index was statistically connected respectively with T stage (2/18), N stage (4/18), grading (6/18), disease-free survival (10/18) and overall survival (4/18). Our review strongly suggests that immunohistochemical staining of Ki-67 correlates with tumoral aggressiveness and worse prognosis in patients affected by laryngeal squamous cell carcinoma. Further high-quality prospective studies should be carried out to confirm our finding and determine the eventual differences between cancers of specific laryngeal subsites.

Challenging a dogma – Surgery yields superior long-term results for T1a squamous cell carcinoma of the glottic larynx compared to radiotherapy

AIMS

The aim of this study was to compare laser surgery, conventional endoscopic surgery and radiotherapy in the treatment of early T1a glottic cancer.

METHODS

We conducted a retrospective analysis of patients with early vocal cord cancer (who underwent either conventional surgery via endoscopy or laryngofissur, or primary radiotherapy) at the Medical University of Vienna. By univariate and multivariate Cox regression models the influence of treatment and other parameters on survival and locoregional control were analysed.

RESULTS

337 Patients were analyzed with a mean follow-up period of 133.8 months. Overall survival rates where similar in all three treatment groups. Five-year, 10-year and 15-year estimates of disease specific survival for laser-treated patients were 100%, for conventional surgery were 100%, 98% and 98%, and for radiotherapy were 96%, 92% and 91%, respectively. Locoregional recurrences were observed after laser surgery in 10%, after conventional surgery in 13% and after radiotherapy in 30% of the patients treated. According to the log-rank test, time to relapse was significantly shorter for irradiated patients compared to patients who underwent surgery (p < 0.0001). Mortality caused by the laryngeal tumour was significantly higher in the radiotherapy group (p = 0.003).

CONCLUSION

Patients undergoing laser or conventional surgery have a significantly lower incidence of locoregional recurrences and longer disease-free intervals when compared to patients treated by radiotherapy.

Pre-treatment proliferation and the outcome of conventional and accelerated radiotherapy

This study investigated the influence of pre-treatment proliferation characteristics, assessed by Ki-67 staining, in patients treated in the CHART trial of accelerated radiotherapy in head and neck cancer. Histological material from 402 patients was collected and stained for the presence and pattern of Ki-67 staining. Locoregional control and overall survival were the main clinical endpoints. Increasing Ki-67 positivity was associated with decreasing differentiation (P < 0.001) and increasing N-stage (P < 0.004). Increasing N-stage was also associated with the progression of proliferation pattern from marginal to random (P < 0.001). Using a multivariate model, a trend was seen towards a greater benefit from CHART in the lower Ki-67 tumours (P = 0.08); this became significant by pooling the low and intermediate Ki-67 groups in comparison with the high Ki-67 group (P = 0.032). Tumours with marginal proliferation pattern showed a lower hazard ratio with CHART versus conventional for locoregional control (P = 0.005). The data presented in this study do not support that a high pre-treatment Ki-67 is associated with a therapeutic benefit from accelerated radiotherapy.

[Treatment of T1N0 glottis carcinoma with radiotherapy. Results at our center and review of the literature]

OBJECTIVE

To evaluate the results of radiotherapy in the treatment of patients with T1N0 glottic squamous cell carcinoma.

MATERIAL AND METHODS

Retrospective study of a cohort of 338 patients with T1N0 glottic carcinoma treated with radiotherapy at our institution between 1985-1997. A review of the literature published during the last ten years was carried out.

RESULTS

Local control with radiotherapy in our patients was 82%, reaching 97% when salvage surgery was included. The local control with radiotherapy in most of the published series ranges between 81.90%.

CONCLUSIONS

Treatment with radiotherapy achieves local control in early glottic carcinomas (T1N0) in 80-90% of cases. In our centre such treatment achieved local control in 82% of cases.

Hyperfractionated-accelerated or conventionally fractionated radiotherapy for early glottic cancer

PURPOSE

To evaluate the effect of shortening overall treatment time by hyperfractionated-accelerated radiotherapy for T2N(0)M(0) glottic carcinomas. Results for local control and survival were calculated and compared to those for T1N(0)M(0) tumors treated with a once-a-day fractionated schedule.

METHODS AND MATERIALS

Between 1990 and 1998, 92 patients with T1N(0)M(0) and 45 patients with T2N(0)M(0) glottic cancers were treated with radical radiotherapy. The T1N(0)M(0) tumors were treated with a once-a-day fractionated schedule lasting 6.5 weeks to a total dose of 62.4 Gy. The T2N(0)M(0) tumors received a split-course hyperfractionated-accelerated treatment over a total of 4.5 weeks to a total dose of 64.6 Gy.

RESULTS

The 5-year local control was 85% for T1N(0)M(0) and 88% for T2N(0)M(0), whereas the 5-year locoregional control was 85% for both groups. The 5-year overall survival was 70% and 53% for T1N(0)M(0) and T2N(0)M(0), respectively. No significant statistical difference was found between the two groups for the parameters analyzed. The number of serious late complications was few and comparable for the two groups.

CONCLUSIONS

Hyperfractionated-accelerated radiotherapy proved beneficial for T2N(0)M(0) glottic cancer, giving local control rates comparable to those for T1N(0)M(0) tumors.

Treatment of early and moderately advanced vocal cord carcinoma with 6-MV X-rays

PURPOSE

Whereas there are many reports regarding treatment of early vocal cord cancer with cobalt 60 or 2-4-MV X-rays, there are still few reports on the results of treatment with 6-MV X-rays. Theoretically, 6-MV X-rays result in greater underdosage of tumor at the air-tissue interface and at the anterior commissure. This paper analyzes the results of irradiation of early and moderately advanced squamous cell carcinoma of the true vocal cord treated exclusively with 6-MV X-rays in a community hospital. The literature pertinent to the issue is reviewed.

METHODS AND MATERIALS

Eighty-three patients with Tis, T1, T2, or T3 squamous cell carcinoma of the true vocal cord were treated with curative intent at Bethesda Memorial Hospital in Boynton Beach, Florida between April 1986 and April 1998. The dose schedules most commonly used were 63 Gy in 28 fractions (2.25 Gy per fraction once a day) for T1 tumors or 74.40 Gy in 62 fractions (1.2 Gy per fraction twice a day) for T2 and T3 tumors. All patients have minimum 2-year follow-up; 63 (76%) have 5-year minimum follow-up.

RESULTS

Local control was achieved in 6 of 6 Tis, 53 of 54 (98%) T1, 8 of 8 T2, and 6 of 6 T3 lesions. No complications were encountered.

CONCLUSIONS

A recent literature review indicates that the treatment of early vocal cord cancer with 6-MV X-rays remains controversial. The dose schedules used in the present paper produced a high rate of local control, a finding that is consistent with reports of other investigators who used dose schedules similar to those used in the present series. However, several other investigators have reported significantly lower rates of local control for T1 or T2 glottic cancer treated with 6-MV X-rays when compared to results obtained with cobalt 60 or 4 MV at their own institution. The latter institutions used lower total doses and/or lower dose per fraction than those institutions reporting high rates of local control with 6 MV. Data from the literature, as well as our own data, are consistent with the following hypotheses: (1) the lower rates of local control reported by several institutions when using 6 MV compared with cobalt or 2-4 MV, using the same radiation dose schedules for each beam energy, indicate that underdosage of mucosal surfaces in the laryngeal air cavity may be a clinically important phenomenon, and (2) time-dose factors, although certainly important for lower energy beams, may be even more important when using 6 MV.

Nuclear BAG-1 localization and the risk of recurrence after radiation therapy in laryngeal carcinomas

BAG-1 is a multifunctional chaperone modulator may contribute to p53-mediated cell cycle arrest. We attempted to investigate whether BAG-1 expression is correlated with prognosis of laryngeal carcinoma patients after radiotherapy. Immunohistochemical analyses revealed BAG-1 expression was present in all laryngeal carcinomas examined, and its expression pattern varied, i.e. cytoplasmic, nuclear and both these staining types. Patients whose tumors predominantly express nuclear BAG-1 have a significantly poor failure-free survival rate after radiotherapy. We thus propose that nuclear BAG-1 localization is a prediction of unfavorable outcome should radiation therapy be undertaken for laryngeal carcinoma patients.