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Nasopharyngeal Carcinoma

Updated : April 15, 2024





Background

Nasopharyngeal carcinoma (NPC), formerly known as lymphoepithelioma, is a cancer of the nasopharyngeal epithelium. The nasopharynx is a tiny, tubular structure that connects the nose to the oropharynx and is located above the soft palate. Squamous cell carcinomas are the most common tumors in this area, and they act differently than other head and neck cancers.

The fossa of Rosenmuller, which is the pharyngeal recess, is the most typical place of origin. The Ebstein-Barr (EBV) is linked to nasopharyngeal tumors (NPC). Nasopharyngeal malignancies have different clinical outcomes based on their histological subtype. Based on histology, the WHO has divided nasopharyngeal cancer into three subgroups.

Keratinizing squamous cell carcinoma (type 1) is related to EBV infection in around 70% to 80% of cases. Type 2 nasopharyngeal cancer is differentiated non-keratinizing carcinoma, while type 3 nasopharyngeal cancer is undifferentiated non-keratinizing carcinoma, which is the most prevalent type. The latter two categories are also the most treatment responsive.

All type 2 and 3 cases are caused by EBV and occur in areas where the virus is prevalent. Basaloid nasopharyngeal carcinoma is a newer, rarer histologic type that is known to be aggressive. Treatment is unaffected by histologic subtypes. In general, nasopharyngeal carcinoma mortality has decreased due to early identification and treatment breakthroughs.

Epidemiology

Nasopharyngeal carcinoma is uncommon in the United States, despite its prevalence in other parts of the world. In some places in China, the rate of infection is as high as twenty-one cases per 100,000 persons.

Nasopharyngeal carcinoma is most typically found in central, south, and southeast Asia, the Arctic, the Middle East, and North Africa. The Incidence in the United States is 0.4 instances per 100,000 individuals, with a greater incidence in those who have immigrated from locations where the disease is more prevalent.

Anatomy

Pathophysiology

Multiple factors influence the development of nasopharyngeal cancer, including genetic vulnerability, environmental variables, and infections like the Epstein-Barr virus (EPV). A region in human leukocyte antigen (HLA) genes on chromosome six have been related to the etiology of NPC in many studies; one of these genes is a region in HLA genes.

Other genes have been discovered in various positions on chromosomes, including 13q12, 3q26, 5p15, 6p21, and 9p21. Many studies show that EBV can activate or inhibit many processes and mechanisms in the host cell while changing it into a cancer cell.

EBV influences cells by delivering encoded proteins or RNA molecules to host cells, and these compounds can be summarised but are not limited to:

  • Latent membrane protein 1 (LMP1): LMP1 is a membrane protein that is encoded by the virus and participates in carcinogenesis. It has a major effect on the nuclear factor kappa B (NF-kB). The activation of NF-kB will have an impact on numerous other proteins involved in cell division, adhesion, differentiation, and survival. TP53, EGFR, VEGF, stemness-related genes, fibronectin, and other factors, proteins, and DNA regulation systems that affect the oncogenesis process are all involved by LMP1. LMP1 is correlated to a bad prognosis.
  • Latent membrane protein 2A (LMP2A): LMP2A is a membrane oncoprotein encoded in viral DNA that plays a role in epithelial-mesenchymal transition, resulting in invasion and migration.
  • MicroRNAs (miRNA): miRNAs are non-coding RNA molecules that have a role in regulating gene expression and so have an impact on cell function and division. EBV expresses a high quantity of miRNAs, such as BamHI-A rightward transcripts (BARTs), which are strongly linked to NPC pathogenesis, such as miR-BART3, miR-BART7, and miR-BART13. These miRNAs can be employed as a biomarker for diagnosis and prognosis because they are abundant and can be excreted extracellularly.
  • Other molecules: such as metastatic tumor antigen (MAT1), are linked to tumor metastasis. The Epstein-Barr nuclear antigen 1 (EBNA1) protein is a nuclear protein connected to virus transcription and lymphatic metastasis.

Etiology

The disease’s origin is complicated by a combination of environmental variables, genetic structure, and EBV infection. Environmental factors, such as smoking in the western population and food ingredients, including nitrosamines, have been suspected of playing a role.

Second, as the overwhelming occurrence in the Chinese population demonstrates, the genetic structure of the demographics involved is equally essential. Finally, EBV infection, in combination with genetic vulnerability, has been linked to the condition.

Genetics

Prognostic Factors

The time of diagnosis and the extent of local invasion determine the prognosis of individuals with nasopharyngeal carcinoma. Patients with localized illness have a poor prognosis. The prognosis for people with locally invasive illnesses is uncertain.

Radiation alone has a 40% survival rate, but when paired with chemotherapy, the survival rate increases from 50% to 80%.Other investigations, such as miRNA and DNA methylation, have been efficient biomarkers for determining the prognosis of this malignancy

Clinical History

Physical Examination

Age group

Associated comorbidity

Associated activity

Acuity of presentation

Differential Diagnoses

Laboratory Studies

Imaging Studies

Procedures

Histologic Findings

Staging

Treatment Paradigm

by Stage

by Modality

Chemotherapy

Radiation Therapy

Surgical Interventions

Hormone Therapy

Immunotherapy

Hyperthermia

Photodynamic Therapy

Stem Cell Transplant

Targeted Therapy

Palliative Care

Medication

 

toripalimab 

It is indicated in the first-line therapy for metastatic or recurrent, locally advanced NPC with cisplatin and gemcitabine with a recommended dosage of 240 mg with a duration of 3-week intervals
It is also indicated for previously treated unresectable or metastatic NPC with disease progression on or after platinum-containing chemotherapy with a recommended dosage of 3 mg/kg with a duration of 2-week intervals



 
 

Media Gallary

References

https://www.ncbi.nlm.nih.gov/books/NBK459256/

https://www.ncbi.nlm.nih.gov/books/NBK558922/

Nasopharyngeal Carcinoma

Updated : April 15, 2024




Nasopharyngeal carcinoma (NPC), formerly known as lymphoepithelioma, is a cancer of the nasopharyngeal epithelium. The nasopharynx is a tiny, tubular structure that connects the nose to the oropharynx and is located above the soft palate. Squamous cell carcinomas are the most common tumors in this area, and they act differently than other head and neck cancers.

The fossa of Rosenmuller, which is the pharyngeal recess, is the most typical place of origin. The Ebstein-Barr (EBV) is linked to nasopharyngeal tumors (NPC). Nasopharyngeal malignancies have different clinical outcomes based on their histological subtype. Based on histology, the WHO has divided nasopharyngeal cancer into three subgroups.

Keratinizing squamous cell carcinoma (type 1) is related to EBV infection in around 70% to 80% of cases. Type 2 nasopharyngeal cancer is differentiated non-keratinizing carcinoma, while type 3 nasopharyngeal cancer is undifferentiated non-keratinizing carcinoma, which is the most prevalent type. The latter two categories are also the most treatment responsive.

All type 2 and 3 cases are caused by EBV and occur in areas where the virus is prevalent. Basaloid nasopharyngeal carcinoma is a newer, rarer histologic type that is known to be aggressive. Treatment is unaffected by histologic subtypes. In general, nasopharyngeal carcinoma mortality has decreased due to early identification and treatment breakthroughs.

Nasopharyngeal carcinoma is uncommon in the United States, despite its prevalence in other parts of the world. In some places in China, the rate of infection is as high as twenty-one cases per 100,000 persons.

Nasopharyngeal carcinoma is most typically found in central, south, and southeast Asia, the Arctic, the Middle East, and North Africa. The Incidence in the United States is 0.4 instances per 100,000 individuals, with a greater incidence in those who have immigrated from locations where the disease is more prevalent.

Multiple factors influence the development of nasopharyngeal cancer, including genetic vulnerability, environmental variables, and infections like the Epstein-Barr virus (EPV). A region in human leukocyte antigen (HLA) genes on chromosome six have been related to the etiology of NPC in many studies; one of these genes is a region in HLA genes.

Other genes have been discovered in various positions on chromosomes, including 13q12, 3q26, 5p15, 6p21, and 9p21. Many studies show that EBV can activate or inhibit many processes and mechanisms in the host cell while changing it into a cancer cell.

EBV influences cells by delivering encoded proteins or RNA molecules to host cells, and these compounds can be summarised but are not limited to:

  • Latent membrane protein 1 (LMP1): LMP1 is a membrane protein that is encoded by the virus and participates in carcinogenesis. It has a major effect on the nuclear factor kappa B (NF-kB). The activation of NF-kB will have an impact on numerous other proteins involved in cell division, adhesion, differentiation, and survival. TP53, EGFR, VEGF, stemness-related genes, fibronectin, and other factors, proteins, and DNA regulation systems that affect the oncogenesis process are all involved by LMP1. LMP1 is correlated to a bad prognosis.
  • Latent membrane protein 2A (LMP2A): LMP2A is a membrane oncoprotein encoded in viral DNA that plays a role in epithelial-mesenchymal transition, resulting in invasion and migration.
  • MicroRNAs (miRNA): miRNAs are non-coding RNA molecules that have a role in regulating gene expression and so have an impact on cell function and division. EBV expresses a high quantity of miRNAs, such as BamHI-A rightward transcripts (BARTs), which are strongly linked to NPC pathogenesis, such as miR-BART3, miR-BART7, and miR-BART13. These miRNAs can be employed as a biomarker for diagnosis and prognosis because they are abundant and can be excreted extracellularly.
  • Other molecules: such as metastatic tumor antigen (MAT1), are linked to tumor metastasis. The Epstein-Barr nuclear antigen 1 (EBNA1) protein is a nuclear protein connected to virus transcription and lymphatic metastasis.

The disease’s origin is complicated by a combination of environmental variables, genetic structure, and EBV infection. Environmental factors, such as smoking in the western population and food ingredients, including nitrosamines, have been suspected of playing a role.

Second, as the overwhelming occurrence in the Chinese population demonstrates, the genetic structure of the demographics involved is equally essential. Finally, EBV infection, in combination with genetic vulnerability, has been linked to the condition.

The time of diagnosis and the extent of local invasion determine the prognosis of individuals with nasopharyngeal carcinoma. Patients with localized illness have a poor prognosis. The prognosis for people with locally invasive illnesses is uncertain.

Radiation alone has a 40% survival rate, but when paired with chemotherapy, the survival rate increases from 50% to 80%.Other investigations, such as miRNA and DNA methylation, have been efficient biomarkers for determining the prognosis of this malignancy

toripalimab 

It is indicated in the first-line therapy for metastatic or recurrent, locally advanced NPC with cisplatin and gemcitabine with a recommended dosage of 240 mg with a duration of 3-week intervals
It is also indicated for previously treated unresectable or metastatic NPC with disease progression on or after platinum-containing chemotherapy with a recommended dosage of 3 mg/kg with a duration of 2-week intervals



https://www.ncbi.nlm.nih.gov/books/NBK459256/

https://www.ncbi.nlm.nih.gov/books/NBK558922/

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