Squamous Cell Carcinoma of the Lip—A Review of Squamous Cell Carcinogenesis of the Mucosal and Cutaneous Junction

EZH2: An analysis of a potential new tumor marker in high-risk localization of cutaneous squamous cell carcinomas

Background

Enhancer of zeste homolog 2 (EZH2) is a transcriptional enzyme implicated in tumor development and is often correlated to poor patient outcomes in various malignancies. The study evaluated various methods for EZH2 expression in lip and ear squamous cell carcinomas (LSCC, ESCC) by matching patients with and without lymph node metastasis (LNM) and further analysis of clinical outcome parameters. EZH2 inhibition therapy has shown promising results in multiple cancer entities, with ongoing research exploring its potential in other malignancies. This approach may also be applicable to high-risk LSCC and ESCC.

Methods

A total of 122 patients who had been surgically treated for LSCC and ESCC were selected to form LNM-positive and LNM-negative matched pairs. EZH2 expression has been examined after immunostaining of the tumor tissue with EZH2-antibodies and quantified as extent, intensity, and score. Pursuing the clinical benefit, we analyzed three different EZH2-score approaches to determine aberrations in EZH2 expression.

Results

While the overall EZH2 extent did not correlate with clinical outcome, the EZH2-intensity and -score was lower in patients who developed a local relapse or distant metastasis (DM). High EZH2-scores correlated with increasing grading, pN-, and American Joint Committee on Cancer-stage. Overall, the carcinoma tissue samples showed a high expression of EZH2 (mean expression > 60%).

Conclusion

The hypothesis of the predictive prognostic contribution of EZH2 in clinical decisions regarding the occurrence of LNM was not substantiated by our data. Nevertheless, the elevated expression of EZH2 we have observed in our findings could be utilized as a pretherapeutic assessment prior to targeted therapies with tazemetostat. Subsequent research should substantiate this hypothesis.

Multivariate analysis of prognostic factors in patients with lip squamous cell carcinoma after surgery

BACKGROUND

Lip squamous cell carcinoma (LSCC) was one of the most common cancer types of head and neck tumors. This study aimed to find more predictors of the prognosis in postoperative LSCC patients.

METHODS

A total of 147 LSCC patients between June 2012 and June 2018 were collected from two tertiary care institutions. There were 21 clinicopathological factors included and analyzed in our study. The univariate and multivariate Cox regression analyses were performed to find the independent prognostic factors for predicting progression-free survival (PFS) and overall survival (OS) in postoperative LSCC patients. The role of adjuvant radiotherapy in various subgroups was displayed by Kaplan-Meier plots.

RESULTS

The 1-, 3-, and 5-year PFS of postoperative LSCC patients were 88.4%, 70.1%, and 57.8%, respectively. Similarly, the 1-, 3-, and 5-year OS of postoperative LSCC patients were 94.6%, 76.9%, and 69.4%, respectively. The results suggested that postoperative LSCC patients with age at diagnosis ≥ 70 years, grade with moderate or poor differentiate, the American Joint Committee on Cancer (AJCC) stage IV, higher systemic immune-inflammation index (SII), surgical margin < 5, and age-adjusted Charlson Comorbidity Index (ACCI) ≥ 5 tend to have a poorer PFS (all P < 0.05). Besides, postoperative LSCC patients with age at diagnosis ≥ 70 years, AJCC stage IV, higher GPS, higher SII, and ACCI ≥ 5 tend to have a worse OS (all P < 0.05). Additionally, postoperative patients with LSCC in the subgroup of ACCI < 5 and AJCC III-IV stage was more likely to benefit from adjuvant radiotherapy, but not for the other subgroups.

CONCLUSION

We identified a series of significant immune-inflammation-related and comorbidity-related clinicopathological factors associated with the prognosis of postoperative LSCC patients by local data from two tertiary care institutions in China, which can be helpful for patients and surgeons to pay more attention to nutrition, inflammation, and complications and finally obtained a better prognosis.

IMP3 Expression as a Potential Tumour Marker in High-Risk Localisations of Cutaneous Squamous Cell Carcinoma: IMP3 in Metastatic cSCC

BACKGROUND

High IMP3 expression is correlated with a worse outcome. Until now, there have been no data about IMP3 expression and clinical outcome for high-risk localisation of squamous cell carcinoma of the skin (cSCC).

METHODS

One-hundred twenty-two patients with cSCC of the lip and ear were included, and IMP3 expression in the tumours was immunohistochemically assessed in different evaluation approaches. Subsequently, subgroups were analysed in a matched pair approach and correlated with clinical pathologic parameters. In the following, different IMP3 analysis methods were tested for clinical suitability.

RESULTS

We found a significant correlation between IMP3 expression and risk for lymph node metastasis, local relapse, and progression-free survival.

CONCLUSIONS

On basis of our data, we suggest a prognostic benefit cutoff value for high (>50%) and low (<50%) IMP3 expression. Thus, IMP3 expression has a high scientific potential for further studies and could potentially be used as a prognostic marker in diagnostic and therapeutic decision-making.

Trends in cutaneous squamous cell carcinoma on the lip incidence and mortality in the United States, 2000-2019

Objective

This study provided a systematic analysis of the trend in incidence and incidence-based mortality for cutaneous squamous cell carcinoma (cSCC) on the lips in the USA using demographic characteristics from the Surveillance, Epidemiology, and End Results (SEER) database.

Methods

Patients diagnosed with cSCC on the lips between 2000 and 2019 from the 17 registries of the USA were identified. Incidence and incidence-based mortality rates were analyzed using SEER*Stat 8.4.0.1 software. This paper calculated incidence rates and incidence-based mortality rates by 100,000 person-years for sex, age, race, SEER registries, median household income ($/year), rural-urban distribution, and primary site. The annual percent changes (APC) in incidence and incidence-based mortality rates were then calculated using joinpoint regression software.

Results

Among 8,625 patients diagnosed with cSCC on the lips from 2000 to 2019, men (74.67%), white (95.21%), and 60-79 years old were the most common population, and 3,869 deaths from cSCC on the lips occurred. The overall incidence of cSCC on the lips was 0.516 per 100,000 person-years. cSCC on the lip incidence rates were highest among men, white, and patients aged 60-79 years old. cSCC on the lip incidence rates decreased by 3.210%/year over the study period. The incidence of cSCC on the lips has been decreasing in all sexes, ages, high- or low-income households, and urban or rural patients. The overall incidence-based mortality rate of cSCC on the lips during 2000-2019 was 0.235 per 100,000 person-years. cSCC on the lip incidence-based mortality rates were highest among men, whites, and people older than 80 years old. cSCC on the lip incidence-based mortality increased by 4.975%/year over the study period. cSCC on the lip incidence-based mortality rates increased for all sexes, races, ages, primary sites, high- or low-income households, and urban or rural patients during the study period.

Conclusion

Among patients in the USA diagnosed with cSCC on the lips from 2000 to 2019, the overall incidence decreased by 3.210% annually, and incidence-based mortality increased by 4.975%/year. These findings update and supplement the epidemiological information of cSCC on the lips in the USA.

Distinctive expression of DNA replication factors in squamous cell carcinomas of the lip, face and oral cavity

OBJECTIVE

Uncontrolled proliferation and aberrations in cell-cycle progression are fundamental issues in cancer. In this study we aimed to determine and compare deoxyribonucleic acid (DNA) replication licensing factors at the mRNA and protein levels among squamous cell carcinomas (SCCs) of the lip, facial-skin and oral cavity.

MATERIALS AND METHODS

A total of 103 lip, oral and face SCCs were immunohistochemically stained with MCM2 (mini-chromosome maintenance 2), geminin, and ki67, and their labeling-indices were calculated. Also, 57 SCCs from the same regions along with their adjacent normal tissues underwent quantitative reverse transcription-polymerase chain reaction analysis.

RESULTS

All three proteins were overexpressed in the studied SCCs, but only geminin (P = 0.004) showed significant difference among the three regions, with higher levels in oral SCCs compared to lip (P = 0.005) and skin (P = 0.024) tumors. Geminin expression did not differ between skin- and lip-SCCs (P = 0.822). MCM2/ki67 ratio was higher in oral- compared to skin-neoplasms (P = 0.039), but no difference was found in geminin/ki67 among the SCC-subsites. There were significant differences in MCM2 and geminin mRNA between carcinomatous- and normal-tissues in all tumors, but not among the three locations.

CONCLUSION

MCM2 and geminin are involved in the tumorigenesis of lip, face and oral SCC at both mRNA- and protein-levels. Geminin may have a role in the site-specific biologic behavior of SCC. Skin SCCs had the highest proportion of licensed non-proliferating cells, while actively proliferating cells were more prominent in oral tumors. Regarding DNA replication, lip SCCs seem to be closer to skin tumors compared to their oral counterparts.

Knowledge, opinions, and practices related to oral cancer prevention and oral mucosal examination among dentists in Moldova, Belarus and Armenia: a multi-country cross-sectional study

INTRODUCTION

Moldova, Belarus, and Armenia are post-Soviet countries with a high rate of heavy smokers and a relatively high age-standardized incidence of oral cancer. However, to our knowledge, there is lack of available information on dentists' knowledge on prevention of oral cancer in the countries in question. Accordingly, this study aimed to assess the knowledge, opinions, and practices related to oral cancer prevention and oral mucosal examination among dentists in Moldova, Belarus, and Armenia.

METHODS

This was a multi-country, cross-sectional study based on a self-administered questionnaire. A structured questionnaire was distributed to 3534 dentists (797 in Chisinau, Moldova, 1349 in Minsk, Belarus, and 1388 in Yerevan, Armenia). Dentists' knowledge about risk factors for oral cancer development and its clinical picture, current practices and opinions with regard to oral mucosal screening and oral cancer prevention, and their consistency to perform oral mucosal examination were assessed. A knowledge score ranging from 0 to 14 points was generated based on each dentist's answer to the questionnaire.

RESULTS

A total of 1316 dentists responded, achieving an overall response rate of 37.2% (34.5% in Moldova; 52.3% in Belarus; 24.2% in Armenia). Most dentists in the three countries correctly identified tobacco (83.8-98.2%) and prior oral cancer lesions (84.0-96.3%) as risk factors for oral cancer. Most dentists correctly identified leukoplakia as a lesion with malignant potential (68.7% in Moldova; 88.5% in Belarus; 69.9% in Armenia), while erythroplakia was identified by much fewer in all three countries. Less than 52% of dentists identified the tongue, rim of tongue, and floor of mouth as the most common sites for oral cancer. The mean knowledge score for all countries combined was 7.5 ± 2.7. The most commonly reported barriers to perform oral mucosal examination were lack of training, knowledge, and experience.

CONCLUSIONS

This study highlights the need for improved oral cancer-related education and training on oral mucosal examination for dentists in Moldova, Belarus, and Armenia. Such skills are essential to enhance oral cancer prevention and to improve the prognostic outcome by early detection.

Lack of documentation of lymph node examination in patients with squamous cell carcinoma of the lower lip

Cutaneous squamous cell carcinoma is the second most common cutaneous malignancy with a 5-year disease-specific survival rate of approximately 90%, which decreases dramatically to 50% in the presence of regional lymph node metastases. We sought to examine clinicians' documentation of pertinent neurological symptoms/signs and lymph node palpation at the time of initial biopsy and treatment using lower lip SCC patients as a cohort. Subsequently, we investigated the correlation between clinical and pathologic SCC features and the aforementioned documentation. A single center, retrospective study of all squamous cell carcinomas of the lower lip biopsied over 10 years was conducted, and univariate models were implemented to correlate the variables. A total of 66 squamous cell carcinomas of the lip in 63 patients were identified. Neurological signs and symptoms were not documented and only three of the tumors were palpated, therefore statistical analysis was not performed. A lymph node exam was documented in 14 of the 63 patients (22%), and statistical analysis showed that among all variables (age, gender, tumor size, tumor stages, tobacco or alcohol use, or history of skin cancer), only the size of the tumor correlated positively with a lymph node examination (RRE 1.15 [95% CI 1.06-1.25], p < 0.001). Our study illustrates a possible practice gap and quality improvement potential in tumor, neurologic, and lymph node examination and documentation in patients with cutaneous squamous cell carcinoma.

Immune checkpoint analysis in lip cancer

The aim of this study was to establish whether PD-L1, PD-1, and markers of the tumor microenvironment (CD4, CD8, FOXP3) could have a prognostic value in squamous cell carcinoma of the lip (LSCC). In patients with histologically proven LSCC, tumor specimens were stained using immunohistochemistry (for PD-1, PD-L1, CD4, CD8, and FOXP3) on paraffin-embedded tissues. Patients with (N+) and without (N-) nodal metastasis were stratified and matched to each other according to prognostically relevant clinicopathological parameters. 58 patients (29 N+ and 29 N-) were included. PD-L1 expression was positive (>1%) in 56.1% (n = 33) of all LSCC cases, but its expression did not differ significantly between metastasis groups (65.5% in N+ versus 48.3% in N-; p = 0.144). Nodal disseminated LSCC showed a tendency for higher PD-L1 expression. None of the analyzed markers showed significant correlation with the risk for nodal disease, or revealed significant prognostic value. Due to their significant expression, PD-L1 and PD-1 are potential targets for checkpoint inhibitor therapy in LSCC. Their expression should be analyzed in advanced and metastasized LSCC cases.

Implication of the New AJCC pT Classification of SCC of the Lip Comparing With Other Oral Subsites

OBJECTIVE

To determine the implication of the new AJCC staging system for pT classification in a cohort of patients with SCC of the lip mucosa and compare it to other oral cavity sites.

METHODS

Retrospective cohort of 744 patients treated between 2002 and 2017, by the Head and Neck Surgery Department of the University of Sao Paulo.

RESULTS

Of 95 lip patients, 42 had pT upstage (58.1% of pT1 to pT2-3 and 50% of pT2 to pT3). Similar DFS/OS observed for those pT1 maintained or upstaged to pT2-3, pT2 patients upstaged to pT3 presented worse OS (49.4% versus 92.3%, P = .032). The comparison between lip and other mouth topographies, denoted better prognosis for pT1-2, but not for pT3-4a. Lip tumors had lower DOI, rates of perineural/angiolymphatic invasion, nodal metastasis, recurrence, and death.

CONCLUSION

The inclusion of DOI to the new pT classification better stratifies patients with SCC of the lip mucosa upstaged to pT3 by assessing inferior OS.

LEVEL OF EVIDENCE

3 Laryngoscope, 2021.

Oral Cancer: Raising Awareness of the Importance of Suspicion in Early Detection

Oral cancer is a significant cause of morbidity and mortality worldwide. In this article we present two cases of potentially innocuous looking lesions, initially thought to be traumatic in origin, but later diagnosed as cancer. The first patient presented with a persistent laceration thought to be caused by an accidental shaving injury, which was subsequently diagnosed as squamous cell carcinoma. The second patient presented with a hyperplastic mucosal lesion, suspected as forming due to denture-clasp irritation, which was subsequently diagnosed as proliferative verrucous carcinoma. The importance of early detection and palpation of suspicious lesions is emphasised in this article.

A nomogram predicting subclinical extension of cutaneous squamous cell carcinoma in Chinese individuals: A retrospective study

Cutaneous squamous cell carcinoma usually extends beyond the visible margin. Little is known about the predictors for cutaneous squamous cell carcinoma with subclinical extension in Chinese individuals. This study aimed to construct a nomogram for predicting the probability of subclinical extension of cutaneous squamous cell carcinoma in Chinese patients.A retrospective analysis was conducted using data from Mohs micrographic surgery-treated cutaneous squamous cell carcinoma patients at a single institution between December 1, 2009 and October 31, 2019. Subclinical extension was defined as a lesion requiring ≥ 2 Mohs stages or with final safe margins of ≥ 5 mm. A nomogram predicting the probability of subclinical extension was constructed using the predictors identified in multivariable analysis.Of 274 patients included, 119 (43.4%) had subclinical extension. In multivariable analysis, male sex (odds ratio [OR], 2.45; 95% confidence interval [CI], 1.40-4.29; P = .002), lesions on mucocutaneous areas (OR, 3.71; 95% CI, 1.34-10.32; P = .012) and extremities (OR, 2.40; 95% CI, 1.20-4.78; P = .013), maximum diameter of 10 to 19 mm (OR, 14.15; 95% CI, 4.24-47.28; P < .001), and 20 to 29 mm (OR, 9.21; 95% CI, 2.80-30.29; P < .001) were associated with subclinical extension. A nomogram incorporating these 3 variables demonstrated promising predictive ability (C statistics = 0.78; 95% CI, 0.67-0.89).The nomogram incorporating sex, tumor location, and maximum diameter can provide individualized prediction for subclinical extension in Chinese patients with cutaneous squamous cell carcinoma. This information may help surgeons determine appropriate margins at the first Mohs stage.

Validation of the American Joint Committee on Cancer Staging in Squamous Cell Carcinoma of the Vermilion Lip

BACKGROUND

The vermilion lip is a unique anatomical junction between cutaneous and mucosal surfaces. Squamous cell carcinoma (SCC) of the vermilion lip (vlSCC) was previously classified as oral SCC (oSCC) under the American Joint Committee on Cancer (AJCC) 7th edition (AJCC7), but has been recategorized as a cutaneous SCC of the head and neck (HNcSCC) in the AJCC 8th edition (AJCC8). We investigated the locoregional control (LRC), disease-free survival (DFS), and overall survival (OS) for the various pathological T categories and disease stages of vlSCC as per AJCC8.

METHODS

We performed a retrospective cohort study of 297 patients diagnosed with vlSCC between January 2004 and February 2019. For this study, vlSCC cases were staged according to both AJCC7 and AJCC8. Kaplan-Meier survival curves and Cox regression models were used to analyze differences in LRC, DFS, and OS between each pT category and disease stage, and log-rank tests were performed for subgroup analysis.

RESULTS

Restaging of vlSCC using the AJCC8 resulted in 19% of patients being upstaged to pT3, and 16% being upstaged to stage III. No patients were downstaged in pT stage or overall stage.

CONCLUSIONS

Our study shows that when the AJCC8 HNcSCC staging system is applied to vlSCC, there are important aberrations leading to unwarranted upstaging of pT1 and redundancy of pT2. Understanding of these limitations are important in considering treatment escalation.

Labial metastasis of renal neoplasia - A diagnostic challenge

INTRODUCTION

Cutaneous spread of solid visceral metastasis is very unusual presentation, usually in breast, lung, colon, ovarian carcinomas, and malignant melanoma. Less than 5% of cases of cutaneous spread are from renal neoplasms.

PRESENTATION OF CASE

We present the case of a 48-year-old woman with a large lower lip tumor whose anatomopathological analysis of the lesion led us to identify a Clear Cell Renal Cell Carcinoma (ccRCC).

DISCUSSION

The clinical manifestations of the ccRCC can be mild, generating a late diagnosis through metastasis of primary neoplasia. Their presentations can be varied, as described in this report.

CONCLUSION

The knowledge of the different types of presentation of CCCR metastases can assist in decision making, but the progression of staging often only allows palliative measures.

Dermatologist-level classification of malignant lip diseases using a deep convolutional neural network

BACKGROUND

Deep convolutional neural networks (DCNNs) can classify skin diseases at a level equivalent to a dermatologist, but their performance in specific areas requires further research.

OBJECTIVE

To evaluate the performance of a trained DCNN-based algorithm in classifying benign and malignant lip diseases.

METHODS

A training set of 1629 images (743 malignant, 886 benign) was used with Inception-Resnet-V2. Performance was evaluated using another set of 344 images and 281 images from other hospitals. Classifications by 44 participants (six board-certified dermatologists, 12 dermatology residents, nine medical doctors not specialized in dermatology and 17 medical students) were used for comparison.

RESULTS

The outcomes based on the area under curve, sensitivity and specificity were 0·827 [95% confidence interval (CI) 0·782-0·873], 0·755 (95% CI 0·673-0·827) and 0·803 (95% CI 0·752-0·855), respectively, for the set of 344 images; and 0·774 (95% CI 0·699-0·849), 0·702 (95% CI 0·579-0·808) and 0·759 (95% CI 0·701-0·813), respectively, for the set of 281 images. The DCNN was equivalent to the dermatologists and superior to the nondermatologists in classifying malignancy. After referencing the DCNN result, the mean ± SD Youden index increased significantly for nondermatologists, from 0·201 ± 0·156 to 0·322 ± 0·141 (P < 0·001).

CONCLUSIONS

DCNNs can classify lip diseases at a level similar to dermatologists. This will help unskilled physicians discriminate between benign and malignant lip diseases. What's already known about this topic? Deep convolutional neural networks (DCNNs) can classify malignant and benign skin diseases at a level equivalent to dermatologists. The lips are a unique feature in terms of histology and morphology. Previous studies of DCNNs have not investigated tumours on specific locations. What does this study add? This study shows that DCNNs can distinguish rare malignant and benign lip disorders at the same rate as dermatologists. DCNNs can help nondermatologists to distinguish malignant lip diseases. What are the clinical implications of this work? DCNNs can distinguish malignant and benign skin diseases even at specific locations such as the lips, as well as board-certified dermatologists. Malignant lip diseases are rare and difficult for less trained doctors to differentiate them from benign lesions. This study shows that in dermatology, DCNN can help improve decision-making processes for rare skin diseases in specific areas of the body.

Neglected Under Lip Cancer

The lip represents an anatomical area of the interface between the skin and oral mucosa. It is, therefore, not entirely surprising that SCC of the lip exhibits mixed features between cutaneous and oral mucosal SCC, namely regarding risk factors and biological behaviour. The main risk factors for lip SCC include ultraviolet radiation exposure, low phototype, tobacco and alcohol use, and immunosuppression. Lip SCC usually presents clinically as a nodule or a tumour with a keratotic surface that commonly ulcerates. There is often a background of actinic cheilitis. The particularly exuberant presentation of our case can most probably be explained by the long evolution of a tumour before the patient reached medical attention. Patients with regional lymph node metastasis are usually offered regional lymph node dissection (usually of the neck). Radiotherapy and/or chemotherapy may be used in advanced cases, particularly in unresectable tumours, tumours with high-risk features and metastatic disease. The large size of a tumour in our case, most probably due to its long evolution, highlights the importance of timely diagnosis to avoid such extreme presentations and the consequent need for more aggressive treatment.

Lip Repair after Mohs Surgery for Squamous Cell Carcinoma by Bilateral Tissue Expanding Vermillion Myocutaneous Flap (Goldstein Technique Modified by Sawada)

Squamous cell carcinoma is the most common malignancy of the lower lip. Environmental factors such as ultraviolet light exposure, arsenic and smoking are contributing factors to the increasing incidence. Mohs surgery is the treatment of choice ensuring the lowest recurrence rates. The closure of the surgical defects, however, can be a challenge. Multiple and versatile methods of reconstructing vermilion defects have been described. Among these options, Goldstein developed the adjacent ipsilateral vermilion flap based on an arterialized myocutaneous flap. The original technique was modified by Sawada based on bilateral adjacent vermilion advancement flap for closure of central vermilion defects. We report the use of bilateral flaps - Sawada’s technique (instead of unilateral as suggested by Goldstein) in medium (2 cm of extension) to large defects (> 2 cm) to achieve an effective and functional reconstruction of vermillion defects after Mohs surgery for lip cancer.