Moderately differentiated laryngeal chondrosarcoma: a comprehensive review of four clinical cases and existing literature

Summary

Introduction: Laryngeal chondrosarcoma (LCS) is a rare, slow-growing malignancy that can mimic common laryngeal pathologies, presenting significant challenges in differential diagnosis. Symptoms such as slow onset of progressive hoarseness, dyspnea, and dysphagia, often asymptomatic in nature, can lead to incidental detection. Given the rarity of this condition, understanding its clinical presentation and management is crucial. Methods: This paper describes four cases of grade 2 LCS treated at our institution, placed within the context of a comprehensive review of current literature on LCS. This review methodically examines the diagnosis complexities, characteristic symptoms, and treatment modalities associated with LCS. Results: While our patients underwent total laryngectomy and bilateral neck dissection due to the advanced stage of the disease, the review reaffirms the preference for conservative, function-preserving methods such as wide excision and partial laryngectomy when the treatment circumstances allow. The review also discusses Transoral robotic surgery (TORS) as a potential new treatment modality and discusses adjuvant therapies. Recent studies suggest that proton beam therapy might be an effective approach. Prognostic indicators play a crucial role in determining outcomes. LCS generally has a favorable prognosis, but high-grade tumors may experience poorer outcomes. As the review notes, the LCS recurrence rate of 25–40% underscores the necessity for long-term patient monitoring and follow-up. Conclusions: These cases enrich existing literature by sharing our experiences in managing grade 2 LCS. Given the rarity of this condition, each case report provides valuable insight, enhancing our understanding of its clinical presentation and management.

Keywords:

Prognosis – head and neck – therapy – laryngeal chondrosarcoma – cartilaginous tumor

Introduction

Laryngeal chondrosarcoma (LCS), traditionally accounting for around 0.07–0.2% of all laryngeal malignancies, has seen a recent potential increase in recognition or incidence, suggested by a rise in case reports, possibly amounting up to 1% or more of these malignancies [1–3]. Although it is the third most common primary malignant bone tumor, its occurrence in the larynx remains relatively infrequent compared to the dominant laryngeal cancers such as squamous cell carcinoma and adenocarcinoma, which constitute the majority of laryngeal malignancies.

The history of LCS dates back to 1816, when the first case was reported by Travers F., who post mortem described ossification and bony growth of the laryngeal cartilages causing deglutition impairment in one of his patients [4].

Since the first case report up to date, only around 650 cases have been documented in the literature, underlining the rarity of this malignancy.

The scholarly landscape of LCS is predominantly characterized by individual case reports and modestly sized case series. Despite this, a few major studies have emerged as the largest examinations of LCS to date. The systematic reviews by Thompson, Chin, and Álvarez-Calderón-Iglesias provide comprehensive overviews of 111, 592, and 381 cases, respectively [5–7]. It is important to note that there is a considerable overlap of patients across these studies. Additionally, two recent large distinct population-based analyses conducted by Dubal and Talati bring valuable population-scale data to a broader understanding of LCS epidemiology and survival rates [8, 9].

The distribution of histological grades of chondrosarcoma may differ between studies; nevertheless, according to recent research, the incidence of high -⁠ -grade chondrosarcomas (grade 2 and 3) appears to be markedly lower, potentially constituting less than a third of all cases [6, 7].

The aim of this study is to contribute to the existing literature by sharing our experiences in managing high-grade LCS at our department. Considering the mentioned rarity of this condition, every single case report holds significant value, providing a richer and more nuanced understanding of its clinical presentation and management.

Case presentation

Case 1

A 70-year-old woman was referred by her general practitioner due to a two -⁠ -year history of progressive paratracheal resistance on the left side of the neck, productive cough, shortness of breath on exertion, and a 15-year history of hoarseness of voice related to her previous work in a chemical laboratory. The patient had no reported pain or swallowing difficulties. An endocrinology examination revealed a suspicious nodule in the right thyroid lobe, with a fine-needle aspiration cytology (FNAC) suggesting medullary carcinoma. However, calcitonin levels were within the normal range. Clinical examination showed restricted adduction of vocal folds and severe subglottic tracheal stenosis caused by a tumorous mass. CT and MRI scans of the neck suggested a chondrosarcoma originating from the cricoid cartilage. A confirmatory biopsy was performed using an open surgical approach on the extralaryngeal part of the tumor, which histologically confirmed grade 2 chondrosarcoma. The multidisciplinary team decided to proceed with total laryngectomy, hemithyroidectomy, and bilateral neck dissection (regions II–III). Final histology results confirmed a high-grade chondrosarcoma originating from the cricoid cartilage, infiltrating the prelaryngeal muscles. No infiltration of the thyroid gland, trachea, or thyroid cartilage was observed. Lymph nodes showed no evidence of malignancy. Additionally, a secondary tumor classified as stage I papillary microcarcinoma was found in the thyroid gland. As a result, adjuvant radiotherapy was indicated, while radioactive iodine therapy was not recommended. Following the completion of adjuvant radiotherapy, a voice prosthesis was surgically inserted. Thereafter, the patient was subjected to routine oncological surveillance and has been followed up for four years without disease recurrence (Fig. 1.1, 3.1, 4, Tab. 1).

 

Case 2

A 76-year-old female patient, with a 6-month history of hoarseness, exertional dyspnea, and exertional stridor, was examined by an ENT specialist. Endoscopy revealed a smooth, spherical swelling in the left posterior part of the subglottis, which was associated with impaired function of the left vocal fold. Subsequently, the patient was referred to our clinic. CT revealed a non-homogeneous mass originating from the cricoid cartilage, eroding its left side and extending to the right, defiguring the left vocal fold and arytenoid cartilage. The mass contained coarse dysmorphic calcifications. MRI showed a T2 hyperintense lesion with cartilage characteristics. A biopsy was performed via laryngofissure with simultaneous tracheostomy. Histological results indicated grade 1 chondrosarcoma. The oncological board decided to proceed with total laryngectomy with insertion of voice prosthesis. Final histological results confirmed grade 2 chondrosarcoma with adequate safety margins, and the tumor did not spread beyond the larynx. No adjuvant therapy was indicated. Seven months after the laryngectomy, the cause of death was cardiopulmonary failure. Autopsy findings revealed no recurrence of the chondrosarcoma (Fig. 1.2, 2, 3.2, Tab. 1).

Case 3

A 64-year-old male presented to our ENT department with a 14-month history of progressive hoarseness and dyspnea. The patient had previously attempted bronchodilators without improvement, and the delay in proper diagnosis was attributed to the COVID-19 pandemic. The patient reported no pain, fever, or weight loss. Inspiratory stridor was present. CT imaging revealed destruction of the posterior part of the cricoid cartilage by a soft-tissue tumorous mass extending into the subglottic region, resulting in subglottic stenosis. No calcifications were identified. Based on the CT findings suggestive of chondroma, the multidisciplinary team decided to proceed with laryngofissure and excision of the tumor. Histological analysis confirmed the diagnosis of grade 2 chondrosarcoma. Total laryngectomy with bilateral neck dissection was performed, and a voice prosthesis was inserted during the surgery. Lymph nodes showed no evidence of malignant cells. Given the extent of the tumor, adjuvant radiotherapy was recommended. The patient opted for regular oncological follow-up and is 4.5 years disease-free post-operatively (Fig. 1.3, 3.3, Tab. 1).

Case 4

A 59-year-old female patient was admitted to a district hospital for acute breathlessness, diagnosed initially as acute laryngitis and tracheitis. She had been observing occasional hoarseness for approximately a year, which she attributed to recurrent lower respiratory tract infections. Upon examination, inspiratory-expiratory stridor was noted, with a dominant inspiratory component. No decrease in oxygen saturation was observed. Endoscopy revealed a unilateral right vocal fold paralysis without defect, and subglottic mucosal protrusion on the right side. Computed tomography (CT) findings included a right-sided subglottic tumor with calcifications, destruction of the thyroid cartilage, elevation and medialization of the right vocal fold, and nodular goiter. No significant lymphadenopathy was evident. Multiple biopsies taken during direct laryngoscopy were non-diagnostic. The multidisciplinary team decided to proceed with total laryngectomy and neck dissection bilaterally. A total thyroidectomy was performed due to the tumor‘s close proximity to the thyroid gland. Subsequent histological analysis confirmed the diagnosis of grade 2 chondrosarcoma. The tumor originated from the cricoid cartilage, causing destruction of the thyroid cartilage and closely abutting the thyroid gland. Final histology indicated complete tumor resection without residual tissue with sufficient resection margins. Lymph nodes showed no evidence of malignancy. No adjuvant therapy was recommended by the oncologist. The patient opted for an electrolarynx as a voice replacement technique. The patient was subjected to regular oncological follow-up. She died 9 years post-operation due to advanced rectal adenocarcinoma. Autopsy findings did not reveal chondrosarcoma locoregional or distant recurrence (Fig. 1.4, Tab. 1).

Discussion

Case reports

The presented cohort, comprised of 4 patients (3 females, 1 male) with a median age of 67 years, exhibited similar symptom trajectories, including progressive hoarseness, progressive or abruptly exacerbated dyspnea, and in one case, a painless cervical mass. The duration of symptoms ranged from 6 to 24 months. In 3 patients, the diagnosis was confirmed via open biopsy (laryngofissure), and in 1 patient, biopsy was taken during direct laryngoscopy. Final histological examination in all cases revealed grade 2 chondrosarcoma. Based on the histological findings, all patients were recommended to undergo total laryngectomy, with 3 patients also undergoing bilateral neck dissection due to the extralaryngeal extent of the tumor, as advised by a multidisciplinary team. Adjuvant radiotherapy was indicated for 2 patients due to close resection margins. None of the patients exhibited lymph node involvement or distant metastasis. No recurrence was observed in any of the patients. Voice rehabilitation, through the insertion of a voice prosthesis, was conducted in 2 patients.

 

Demographics and epidemiology

According to population studies, LCS has significant gender and racial disparity. LCS is predominantly diagnosed in men, reflecting a male to female ratio of 3 : 1, which aligns with the sex ratio reported for other types of laryngeal cancer [5, 6, 8–10]. Moreover, LCS predominantly affects white individuals, who account for over 90% of diagnosed cases, as per the study by Adeola et al. [10]. No relationship to tobacco use or alcohol consumption has been proved [5]. LCS generally occurs in older people, with the average age at diagnosis being around 62 years as reported in several studies [5, 6, 8–11].

A heightened prevalence in older age groups and the male population implicates the potential influence of environmental exposure (such as air pollution), as proposed in studies by Adeola, Chin, and Fasunla [6, 10, 12]. Thus, further research into these demographic trends may illuminate opportunities for developing more efficient prevention and treatment strategies [6, 10, 12].

 

Classification

Enneking et al. developed a staging system in 1986 for bone sarcomas, including chondrosarcomas, which categorizes tumors based on grade (stage I for low grade and stage II for high grade) and further subdivides these stages according to the local anatomic extent. The system also includes a stage III category for patients with distant metastases [13, 14].

The American Joint Committee on Cancer (AJCC) developed a tumor, node, and metastasis (TNM) staging system for primary bone tumors, including chondrosarcomas, in its fifth edition (AJCC Staging Manual 1997). Despite several modifications, this staging system has not been widely adopted for clinical use. The latest revision in 2017 (eighth edition) introduced separate and distinct TNM classifications (Tumor, Node, Metastasis) for primary bone tumors arising from different locations. This includes chondrosarcomas arising from the appendicular skeleton, trunk, skull, and facial bones, as well as those arising from the pelvis and spine can also be used for LCS [15]. The clinical application of this updated TNM staging system in practice remains to be seen.

 

Pathology and classification

LCS arises from cartilaginous tissue in the larynx [5]. According to the definition endorsed by the World Health Organization (WHO), head and neck chondrosarcoma (HNCS) is a malignant tumor characterized by the formation of cartilage, but not of bone, by tumor cells [16]. The etiology of LCS is not yet fully understood, but various theories have been proposed. One theory suggests that LCS may result from remnants of cartilage due to failures of chondrocranium ossification, while another theory suggests that initial disordered ossification of laryngeal cartilages may lead to LCS. Mesenchymal pluripotential cells differentiating into a chondrocytic phenotype via malignant transformation have also been proposed as a potential mechanism. Ischemic change in chondroma and the development of LCS in nonhereditary skeletal disorders have also been suggested as possible factors [17].

Histologically, LCS is characterized by the presence of atypical chondrocytes and various degrees of nuclear atypia [5]. The diagnostic criteria for malignant cartilaginous neoplasms including LCS, established by Lichtenstein and Jaffe, are based on cellular features [18]. These criteria include the presence of many cells with plump nuclei, occasional cells with two nuclei, and giant cartilage cells with single or multiple nuclei. Vascular invasion is not a reliable diagnostic criterion as it can be present in both benign and malignant neoplasms.

The classification of LCS is primarily based on histological features and tumor grade [5]. The Evans et al. grading system is commonly used and categorizes chondrosarcomas into three grades: grade 1 (well differentiated, low--grade), grade 2 (moderately differentiated, high-grade), and grade 3 (poorly differentiated, high-grade) [19]. Furthermore, the WHO has classified additional variants of chondrosarcoma, including conventional (primary and secondary), periosteal, dedifferentiated, mesenchymal, and clear cell variants [16].

To establish a definitive diagnosis, incisional biopsy and histopathological examination are typically performed [5]. However, biopsy results can be challenging to obtain due to the firmness of the lesion, and sometimes, they may be inconclusive. Therefore, examining the entire specimen is recommended to ensure an accurate diagnosis.

 

Clinical presentation

LCS exhibits a range of specific symptoms during clinical presentation. The origin of LCS varies according to the site within the larynx and involvement of different cartilages. Approximately 60–75% of LCS cases arise from cricoid cartilage (especially the anterior surface of the posterior lamina), 15–20% from thyroid cartilage, 3–5% from arytenoid cartilage, and in less than 1% from the epiglottis [5, 6, 11, 20, 21].

Clinical manifestations of head and neck sarcomas, including LCS, often present as a painless mass, accounting for 60–92% of cases [22, 23]. The most common manifestations of LCS include progressive hoarseness, dyspnea, and dysphagia [24]. These symptoms vary depending on the tumor‘s location, with dyspnea being more prevalent when the neoplasm extends anteriorly into the airway lumen, and dysphagia occurring when it develops posteriorly into the pharynx [5, 6, 11, 24]. Over time, patients may adapt to the gradual narrowing of the airway until an acute episode of inspiratory dyspnea sometimes even necessitates emergency tracheotomy. In cases where the tumor originates from the thyroid cartilage, the major complaint may be the presence of a palpable lump in the neck. Furthermore, vocal fold paralysis can serve as an early sign of cricoid chondrosarcoma and may result from recurrent nerve involvement or fixation of the cricoarytenoid joint [24].

In some cases, LCS may be discovered incidentally during imaging studies or laryngeal examinations conducted for unrelated reasons. As chondrosarcomas are typically slow-growing tumors, they can remain asymptomatic for a significant period. The incidental detection of LCS poses challenges in establishing a definitive diagnosis and determining the appropriate course of treatment [11].

Lymph node metastasis is generally less common in sarcomas, with distant metastasis being more frequent due to hematogenous spread. When lymph node metastasis does occur, it is typically associated with high-grade tumors [11, 25, 26].

Duration of symptoms in the study by Aalling et al. (2020) ranged from 1 to 144 months, with a median of 5 months. The time to histological diagnosis from the first visit at the ENT department had a mean of 34 days and a median of 14 days [23]. Although no significant association was found between symptom duration, time to diagnosis, and overall mortality. Other studies of the effect of prolonged diagnostic delay on mortality report very divergent findings (better, worse, or unaltered mortality), hence further research is needed to explore the impact of these factors on the prognosis of LCS [27, 28].

Due to the rarity and diverse clinical presentations of LCS, there can be delays in diagnosing the condition. The initial symptoms of LCS may mimic those of more common laryngeal pathologies, leading to misdiagnosis or a prolonged diagnostic workup.

 

Diagnosis and differential diagnosis

Biopsy

Due to the submucosal location and rubbery consistency of the lesions, obtaining an adequate biopsy sample can be challenging. It is recommended to perform the biopsy under general anesthesia, and in some cases, a preliminary tracheotomy may be necessary to facilitate access to the lesion [29]. A generous biopsy sample is essential to provide a reliable picture of the tumor‘s diagnostic macroscopic and microscopic features, as LCS often contains areas with varying degrees of differentiation [5].

Obtaining a definitive diagnosis of LCS often involves incisional biopsy and histopathological examination [5]. Fine-needle aspiration or core-needle biopsy may be used in conjunction with radiographic and clinical findings as a safe and cost-effective diagnostic measure [29–31]. However, it should be noted that biopsy results can be challenging to obtain due to the firmness of the lesion or may be inconclusive due to incomplete assessment of focal invasion [5]. Considering that the tumor can have a different microscopic appearance in different areas (different cellularity, different degree of cytologic atypia, etc.), therefore some experts argue for the examination of the entire specimen rather than relying solely on biopsies, emphasizing the importance of a comprehensive evaluation (see case report of patient No. 2) [5]. Differential diagnosis between laryngeal chondroma and low-grade chondrosarcoma can be extremely difficult, leading to a conservative interpretation where laryngeal chondroma is considered indistinguishable from LCS to ensure appropriate treatment [5].

 

Imaging methods

Computed tomography (CT) scans, which are commonly used, provide detailed anatomical information and are particularly useful in demonstrating the most specific feature of these tumors, which is popcorn calcifications [5, 17, 31]. These tumors typically appear as multilobulated submucosal masses with varying degrees of calcification that are locally invasive and can cause destruction of surrounding cartilage, soft tissues, and bones [5, 32]. CT with contrast medium is useful for assessing the extent of the lesion and suggesting the presence of a cartilaginous tumor [5].

On the other hand, MRI is valuable for evaluating the internal characteristics of LCS. On MRI, these tumors typically exhibit a high T2 signal return due to the cartilaginous tumor matrix, while smaller areas of signal drop-out correspond to the popcorn calcifications [5, 33]. There are no specific post-enhancement patterns described in the literature, with both peripheral and diffuse central enhancement reported [33]. This combination of CT and MRI imaging techniques allows for a comprehensive evaluation of LCS, aiding in their diagnosis and guiding treatment decisions.

 

Laryngoscopic examination

Flexible or rigid endoscope is used to visualize the larynx and assess the extent and characteristics of the tumor. LCS typically appears as a submucosal mass, often originating from the cricoid cartilage or other laryngeal structures [30]. The tumor may present as a well-defined, firm lesion, which may cause displacement or obstruction of nearby structures. In some cases, LCS can infiltrate the surrounding tissues, leading to erosion of cartilage and bone. Laryngoscopic examination helps in assessing the extent of tumor involvement and guides treatment decisions. It allows for the collection of biopsy samples for histopathological examination, which is essential for definitive diagnosis [5].

Currently, there is a lack of available literature addressing the use of Narrow band imaging (NBI), IMAGE 1S technology, or enhanced contact endoscopy for diagnosis of LCS.

LCS, being sarcomas and not epithelial lesions, their diagnostic evaluation using these endoscopic methods might not be as beneficial as in squamous cell carcinoma.

 

Differential diagnoses

Differential diagnoses of LCS include chondroma, chondroblastic osteosarcoma, fibrosarcoma, myxoid liposarcoma, embryonal rhabdomyosarcoma, spindle cell squamous carcinoma with cartilaginous metaplasia, and chondrometaplasia [24].

 

Treatment

Surgery

According to the review by Chin et al., local excisional therapy and total laryngectomy were the most commonly reported therapies, with 35% of cases undergoing each of these procedures. Partial laryngectomy was performed in approximately 18% of cases, while laser and endoscopic excision were performed in less than 5% of cases each, and microlaryngoscopic excision in less than 2% of cases (excluding surgeries that were not otherwise specified) [6].

The choice of treatment option depends on factors such as tumor size, grade, and location. Large and bulkier tumors may require more radical surgery to ensure adequate negative margins. However, the preservation of laryngeal function is a paramount goal in management, and attempts are made to preserve organ function whenever possible [10, 34–36]. A conservative, function-preserving approach such as wide excision with a sufficient margin of normal, uninvolved cartilage achieved through endoscopic removal, laryngofissure, thyrotomy, partial laryngectomy, or crichotracheal resection with primary anastomosis is generally favored over radical surgery [5, 10].

The extent of the tumor, its invasiveness, and the percentage of cricoid cartilage involvement are important factors in determining the appropriate surgical approach. For instance, partial laryngectomy or endoscopic resection may be recommended for smaller, low-grade tumors, while larger or high-grade tumors may require more radical surgery, such as total laryngectomy [37, 38]. As of today, there are no official guidelines regarding the treatment of laryngeal chondrosarcoma. Schleich et al., in their multicentric 2023 study involving 43 patients, presented the following recommendation: larynx preservation for grade 1 and 2 tumors, particularly when a definitive tracheostomy due to bilateral extension is unnecessary (even with positive surgical margins), and advocate total laryngectomy in cases of grade 3 tumors [35].

The necessity of neck dissection for chondrosarcomas remains questionable. Generally, neck dissection is advised when there is a clinical suspicion of metastatic involvement in the neck lymph nodes, a situation more likely with high-grade tumors [9, 26, 29]. Our patient cohort, all of whom underwent neck dissection and showed no signs of metastasis, illustrates the minimal risk of neck metastases in this disease.

Comparing the outcomes of different treatment options, studies have shown that partial laryngectomy has a higher 1-, 5-, and 10-year overall survival rate compared to total laryngectomy [10, 35]. According to Adeola et al., the 10-year survival rate for patients undergoing partial laryngectomy is reported to be 85%, while patients undergoing total laryngectomy have a 66% survival rate over the same period [10]. Schleich et al. reported that conservatively treated patients had a 5-year overall survival rate of 100% (with 42% requiring secondary total laryngectomy), compared to an 83% survival rate for patients initially undergoing total laryngectomy. The conservative approach was predominantly chosen for significantly younger patients [35]. These findings suggest that partial laryngectomy could offer comparable or better long-term survival outcomes, which may be partially attributed to the selection of younger patients with fewer comorbidities and the preference for treating less aggressive or smaller tumors, among other contributing factors.

 

Transoral robotic surgery

Transoral robotic surgery (TORS) has emerged as a potential treatment option for selected cases of LCS. While most studies have primarily focused on the surgical and oncological outcomes of TORS in oropharyngeal or supraglottic carcinoma, a limited number of small case series have explored the safety and efficacy of TORS in total laryngectomy (TORS-TL) for LCS [39].

Based on available evidence, TORS-TL appears to be a safe and useful approach for selected laryngeal tumors or a nonfunctional larynx [40–42]. The procedure is associated with low blood loss, acceptable robotic set-up time compared to other TORS procedures, improved wound healing, and functional results [40–42]. However, the operative time for TORS--TL is relatively longer than that of open total laryngectomy [41]. TORS-TL appears to be a promising surgical option for selected cases of LCS, but further studies, including international multicenter controlled trials, are warranted to assess the efficacy and limitations of TORS-TL compared to open TL.

 

Adjuvant therapy

Adjuvant therapy with radiotherapy and chemotherapy is generally considered ineffective in the management of LCS. Radiotherapy and chemotherapy were used as primary therapies in only a small percentage of cases, with rates of 0.8% and 0.2%, respectively [6]. There is a lack of consensus regarding the use of adjuvant therapy, and its role is typically limited to cases where the tumor is unresectable or surgical resection is not clinically feasible [6, 43].

The limited efficacy of radiotherapy and chemotherapy in LCS may be attributed to the tumor‘s low-grade and relatively indolent nature. These treatment modalities have shown limited effectiveness in chondrosarcomas in other anatomic sites as well [6].

Recently, proton beam therapy has shown promise as a treatment option for primary LCS. Studies on skull base chondrosarcomas treated with proton therapy have demonstrated excellent outcomes, including high long-term local control rates and disease-specific survival rates. The use of proton therapy allows for more conformal treatment, minimizing radiation dose to surrounding healthy structures, and enabling safer dose escalation to the treatment target. Additionally, proton therapy has been associated with minimal morbidity and preservation of vocal function. While experiences with proton therapy in LCS are limited, extrapolation from the skull base chondrosarcoma literature suggests that proton therapy may be an effective approach for LCS as well [44, 45].

Consequently, the primary focus of treatment still remains on surgical management, aiming to achieve complete excision with negative margins while preserving laryngeal function [10]. Adjuvant therapy should be considered judiciously and individualized for cases where it may offer additional benefits, such as in unresectable tumors and in cases where surgical margins are inadequate [11, 37, 46–48].

 

Prognosis

The overall prognosis of LCS, generally favorable, is influenced by various factors, including tumor stage based on TNM classification and tumor grade [23]. Surgical margins, age, histological subtype, and anatomical location also play important roles as prognostic indicators [22, 25, 49, 50]. Achieving clear surgical margins can be challenging due to the tumor‘s proximity to vital structures in the head and neck region [51].

 

Survival rates

Survival rates for LCS can vary depending on several factors. The five-year survival rate has been reported to range from 78% to 100% [10, 38]. Talati et al. examined 348 cases and reported 1-, 5-, and 10-year survival rates of 95.7%, 88.2%, and 66.3%, respectively [9]. A study by Adeola et al. found a 10-year overall survival rate of 85% for patients who underwent partial laryngectomy, while total laryngectomy was associated with a 66% survival rate over the same period [10]. Factors such as younger age, private insurance, treatment at academic or high-volume centers, lower comorbidity scores, lower tumor grade, smaller tumor size, primary surgery, and more extensive surgical interventions were associated with better survival outcomes [9]. Conservative function-preserving surgeries have been shown to improve quality of life without significantly impacting long-term survival diagnosis [11, 37, 48]. However, it is important to note that these studies focused on low -⁠ and intermediate-grade cases, and high-grade tumors may have a poorer prognosis.

 

Recurrence rates

Several studies have shed light on recurrence rates of LCS. The recurrence rate of LCS is reported to be between 25% and 40% in the literature. Factors such as incomplete excision and higher tumor grade contribute to the development of recurrences [11, 37, 48]. Recently in a systematic review of 592 cases, Chin et al. reported that patient outcomes were analyzed in 475 cases, with recurrences encountered in 24.2% of cases [6]. Another recent study of 51 patients with a median follow-up of 90 months developed recurrence in 35% of cases and disease-specific 5 -⁠ and 10-year mortality rates were 22% and 27% respectively [23].

 

Follow-up

Long-term follow-up is crucial for monitoring recurrences and ensuring optimal patient outcomes. Aalling et al. emphasized the importance of a comprehensive evaluation and follow-up in a study on head and neck sarcomas. The study found that the average follow-up time for 383 cases was 61.9 months, ranging from 0 months to 360 months [23]. This underscores the need for long-term monitoring and surveillance in patients with LCS.

 

Metastases

According to clinical series and systematic reviews, metastases were observed in 1.9-5.5% of patients, primarily affecting the lungs (more than 70%), bones, and liver [5, 7, 8, 35]. Involvement of cervical lymph nodes is generally reported as rare (up to 1% of cases), with a higher assumed prevalence in high-grade tumors [9, 26]. However, the specific rates for high-grade tumors are not consistently reported, and further research may be needed to determine the exact metastatic potential of high-grade LCS.

 

Conclusion

Given its low frequency, there is not a uniform diagnostic and treatment approach for LCS. Strategies for its management largely stem from individual case reports. This review summarizes the current understanding from the literature on this issue and various treatment options, including modern modalities. Although the literature increasingly emphasizes conservative surgical methods, it‘s important to consider different approaches for low-grade and high-grade variants. Literature findings indicate that high-grade LCS has a worse prognosis, which includes specific survival rates, recurrence rates, and metastatic potential. We believe that our experiences in treating high-grade (G2) LCS will contribute to the current literature on this rare disease.