Cases Of Pharyngeal Cancer Research Articles

Histomorphometric features of oral tumors in Hyderabad, Pakistan.

Introduction: Oral cancers (oral cavity cancers) are the eleventh most commonly occurring cancers globally. The annual incidence of oral cancer is around 0.27 million cases while 0.13 million cases of pharyngeal cancers excluding nasopharynx occurring in developing countries. The incidence and mortality caused by these cancers show variability according to the geographic location in which it is diagnosed.
 Objectives: To evaluate the histomorphometric features, tumours arising at oral region, among patients in Isra University, Hyderabad.
 Methodology: This cross-sectional study was conducted at Isra University Hyderabad between January 2018 to December 2020. Patients; aged 18 or above of either gender; presented with chronic oral ulcer for ≥ 3 months duration, growth or swelling in the oral cavity were included in the study after taking consent. The morphological and histopathological findings of all the tissues after taking biopsy from the lesion were evaluated and finding recorded in a pre-design proforma.
 Results: During study period total 143 biopsies performed; 89(62.2%) were male patients while 54(37.8%) were female patients. Most (39.20%) of the patients belongs to age group of 43-52 years. Most commonly involved tumors location was the buccal mucosa/cavity (34.2%) followed by gums and alveolus (25.2%). Biopsy data after histopathological evaluation revealed that majority of patients were suffering from the squamous cell carcinoma (92.3%). Majority (35.0%) of patients were in stage II of TNM staging while half (50.3%) of the patients were in advance stages (stage III and IV).
 Conclusion: Buccal mucosa/cavity is the most common anatomical site for oral carcinoma with predominance of middle age group and male. Oral squamous cell carcinoma is the most prevalent oral cancer with majority of patients presented in advance stages (III and IV) and grade (II) of tumor. 
 
 Keywords: Buccal mucosa, Oral tumors, Squamous cell carcinoma.

Demography and Histopathological presentations of oral and maxillo-facial region tumours in Jamshoro, Pakistan.

Introduction: Oral and Pharyngeal cancers are the sixth most common cancer globally. In developing countries, the annual incidence of oral cancer is around 275,000 cases while 130,300 cases of pharyngeal cancers excluding naso-pharynx. Salivary glands tumors are rare accounting for less than 5 % of tumors of head and neck region. The annual incidence of these tumors is 0.05 to 2 cases per 100,000 populations. Majority (over two third quarters) of salivary gland tumors occurs in the parotid glands of which most of them (2/3rd) of them are benign in nature. While most common parotid gland’s benign tumor is Pleomorphic Adenoma.
 Objective: To assess the morphology and histopathological features of oral and maxillo-facial region tumours among the patients in Liaquat University Hospital, Jamshoro, Sindh.
 Methodology: A Cross-sectional study was conducted at Liaquat University Hospital, Jamshoro. Data was collected regarding socio-demographic features, anatomical location of tumours and relevant history of patients admitted at surgical, medical and ENT units of Liaquat University Hospital, Jamshoro from January 2016 to January 2018. Histopathological diagnostic record was collected from Research and Diagnostic Laboratory of Liaquat University Hospital, Jamshoro.
 Results: A total of 160 biopsies were collected from surgical, medical and ENT units of Liaquat University Hospital with maximum (43%) of biopsies were from ENT unit. Most (51%) tumours were benign and 37% were malignant in nature. These tumours of oral and maxillo-facial region were mostly (38%) located in parotid region. Histopathological findings of this study revealed that majority (51%) tumours were Pleomorphic adenoma while (20%) of malignant tumours were Mucoepidermoid Carcinoma.
 Conclusion: Based on findings of the study, we conclude that the most common anatomical location of oral and faciomaxillary tumours, in either gender, is parotid region. The majority of oral and faciomaxillary tumours were benign; frequently occurring benign tumour was pleomorphic adenoma while most frequent malignant tumour was Muco-epidermoid Carcinoma.
 
 Key Words: Faciomaxillary tumours, Salivary glands, Pleomorphic adenoma.

CANCER EPIDEMIOLOGY IN THE TOMSK REGION

The present study was undertaken to evaluate the incidence of pharyngeal cancer in the Tomsk region for the period between 2007 and 2015. Approximately 27 new cases of pharyngeal cancer are annually diagnosed in the region. Between 2007 and 2015, the pharyngeal cancer incidence in males was reported to be higher (80.9 %) than in females. The incidence rate of oropharyngeal cancer was 73.4 %. This incidence rate was not stable over time, and it was 2.2 per 100,000 population in 2015. In 2015, the pharyngeal cancer incidence in the Tomsk region was the highest in the Siberian Federal District (2.3 compared to 0.4) The pharyngeal cancer incidence was higher in rural than urban areas. High percentage of patients with advanced-stage disease and one-year mortality was registered in the region.

Genetic variants in nicotine addiction and alcohol metabolism genes, oral cancer risk and the propensity to smoke and drink alcohol: a replication study in India.

BackgroundGenetic variants in nicotinic acetylcholine receptor and alcohol metabolism genes have been associated with propensity to smoke tobacco and drink alcohol, respectively, and also implicated in genetic susceptibility to head and neck cancer. In addition to smoking and alcohol, tobacco chewing is an important oral cancer risk factor in India. It is not known if these genetic variants influence propensity or oral cancer susceptibility in the context of this distinct etiology.MethodsWe examined 639 oral and pharyngeal cancer cases and 791 controls from two case-control studies conducted in India. We investigated six variants known to influence nicotine addiction or alcohol metabolism, including rs16969968 (CHRNA5), rs578776 (CHRNA3), rs1229984 (ADH1B), rs698 (ADH1C), rs1573496 (ADH7), and rs4767364 (ALDH2).ResultsThe CHRN variants were associated with the number of chewing events per day, including in those who chewed tobacco but never smoked (P = 0.003, P = 0.01 for rs16969968 and rs578776 respectively). Presence of the variant allele contributed to approximately 13% difference in chewing frequency compared to non-carriers. While no association was observed between rs16969968 and oral cancer risk (OR = 1.01, 95% CI = 0.83– 1.22), rs578776 was modestly associated with a 16% decreased risk of oral cancer (OR = 0.84, 95% CI = 0.72– 0.98). There was little evidence for association between polymorphisms in genes encoding alcohol metabolism and oral cancer in this population.ConclusionThe association between rs16969968 and number of chewing events implies that the effect on smoking propensity conferred by this gene variant extends to the use of smokeless tobacco.

Incidence and mortality of oral cavity and pharyngeal cancer in China, 2009

To analyze the incidence and mortality of oral cavity and pharyngeal cancer in cancer-registration areas of China in 2009. We collected data about incidence of oral cavity and pharyngeal from 72 cancer registry sites of National Central Registry Database in 2009, covering 85 470 522 person (57 489 009 were from urban areas, 27 981 513 were from rural areas).Incidence and mortality rates, proportions, cumulative rate (0-74 years old), cut rate (35-64 years old), age-specific rate were then calculated and analyzed respectively. The age-standardized rate was calculated and adjusted by the Chinese standard population in 1982 as well as the Segi's world standard population. There were 2803 new diagnosed oral cavity and pharyngeal cancer cases, 1793 male and 1010 female, with the sex ratio at 1.78: 1. The crude incidence rate of oral cavity and pharyngeal cancer was 3.28/100 000(2803/85 470 522). The crude incidence rate of males was 4.15/100 000(1793/43 231 554) while it was 2.39/100 000(1010/42 238 968) among females. The age-standardized incidence rates by Chinese standard population (ASIRC) and the world standard population were 1.72/100 000 and 2.23/100 000 respectively, and the cumulative rate and cut rate was separately 0.26% and 4.02/100 000. The crude incidence and ASIRC of oral cavity and pharyngeal cancers were 3.87/100 000 (2225/57 489 009) and 1.97/100 000 in urban areas, whereas in rural areas, they were 2.07/100 000(578/27 981 513) and 1.17/100 000. There were 1172 death cases, including 825 males and 347 females. The crude mortality rate was 1.37/100 000 (1172/85 470 522), while it was 1.91/100 000(825/43 231 554) among males and 0.82/100 000(347/42 238 968) among females. The age-standardized incidence rates were 0.64/100 000 and 0.88/100 000 respectively, by Chinese standard population (ASMRC) and the world standard population. The cumulative mortality rate (0-74 age years old) and cut rate were separately 0.10% and 1.34/100 000. The mortality and ASMRC were 1.59/100 000(915/57 489 009) and 0.72/100 000 in urban areas, whereas in rural areas, they were 0.92/100 000(257/27 981 513) and 0.48/100 000 respectively. Both the incidence and mortality of oral cavity and pharyngeal cancer in China were still low in 2009.

Identifying incident oral and pharyngeal cancer cases using Medicare claims

BackgroundBaseline and trend data for oral and pharyngeal cancer incidence is limited. A new algorithm was derived using the Surveillance, Epidemiology, and End Results (SEER)-Medicare linked database to create an algorithm to identify incident cases of oral and pharyngeal cancer using Medicare claims.MethodsUsing a split-sample approach, Medicare claims’ procedure and diagnosis codes were used to generate a new algorithm to identify oral and pharyngeal cancer cases and validate its operating characteristics.ResultsThe algorithm had high sensitivity (95%) and specificity (97%), which varied little by age group, sex, and race and ethnicity.ConclusionExamples of the utility of this algorithm and its operating characteristics include using it to derive baseline and trend estimates of oral and pharyngeal cancer incidence. Such measures could be used to provide incidence estimates where they are lacking or to serve as comparator estimates for tumor registries.

Regular dental visits are associated with earlier stage at diagnosis for oral and pharyngeal cancer

Oral and pharyngeal cancer patients diagnosed at an advanced stage experience increased morbidity and mortality relative to those with localized disease. The aim of this study was to assess the impact of dental insurance status and regularity of dental visits on early detection of oral and pharyngeal cancer. We examined the relationship of dental insurance and frequency of dental visits with stage at diagnosis among 441 oral and pharyngeal cancer cases from a population-based study of head and neck cancer. Ordinal logistic regression models were used to assess the association with stage, and tumor (T) and nodal (N) classification. Never or rarely going to the dentist was associated with being diagnosed at higher stage for oral and pharyngeal cancer (cumulative OR = 2.28, 95 % CI: 1.02-5.10) and oral cancer (cumulative OR = 9.17, 95 % CI: 2.70-31.15) compared to those going to the dentist at least annually. Oral and pharyngeal cancer patients who went to the dentist infrequently (cumulative OR = 1.82, 95 % CI: 1.09-3.05) or rarely/never (cumulative OR = 3.24, 95 % CI: 1.59-6.57) were diagnosed with a higher T classification compared with those who went at least annually. Receipt of regular dental examinations at least annually may reduce the public health burden of oral and pharyngeal cancer by facilitating earlier detection of the disease.

Cholecystectomy and risk of laryngeal and pharyngeal cancer

Duodeno-gastro-esophageal reflux of bile might cause laryngeal and pharyngeal cancer, but more research is required. Since cholecystectomy is followed by an increased risk such reflux, the risk of developing laryngeal or pharyngeal cancer after cholecystectomy was addressed. A population-based cohort study was conducted in Sweden during the period 1965-2008. The number of laryngeal or pharyngeal cancer cases observed in a large cohort of cholecystectomized patients was compared with the expected number, calculated from the entire Swedish population of corresponding age, gender and calendar year. Risk of laryngeal or pharyngeal cancer was calculated as standardized incidence ratio (SIR) with 95% confidence interval (CI). The cholecystectomy cohort included 345,251 patients who were followed up for 1-43 years and contributed 4,854,969 person-years at risk. The 192 new cases of laryngeal cancer and the 175 cases of pharyngeal cancer were not greater than the expected, providing SIR 0.99 (95% CI 0.85-1.14) and SIR 1.06 (95% CI 0.91-1.23), respectively. A longer latency period after cholecystectomy was not associated with any increased risk of any of these tumors. No differences between age groups or sexes were detected. Analyses restricted to verified squamous-cell carcinomas revealed similar results. In conclusion, cholecystectomy does not appear to be followed by any increased risk of laryngeal or pharyngeal cancer.

Abstract 2818: Vitamin or mineral supplement intake and the risk of head and neck cancer: Pooled analysis in the INHANCE consortium

Abstract Background. Head and neck cancer (HNC) is a significant cause of morbidity and mortality, with over half a million cases worldwide each year. While high fruit and vegetable intake is thought to be protective against HNC, it is unclear whether vitamin and mineral supplement intake is associated with decreased risk of these malignancies. Previous case-control studies in the US have suggested vitamin E supplement intake is inversely associated with oral cavity and pharyngeal cancers. In a large randomized controlled trial, supplementation with alpha-tocopheryl acetate and/or beta-carotene was not associated with upper aerodigestive tract cancer incidence; however an inverse association was suggested for early stage laryngeal cancers. Methods. We analyzed individual-level pooled data from 12 case-control studies (7,002 HNC cases and 8,383 controls) participating in the International Head and Neck Cancer Epidemiology (INHANCE) consortium. There were a total of 2,028 oral cavity cancer cases, 2,465 pharyngeal cancer cases, and 874 laryngeal cancer cases. Odds ratios (OR) and 95% confidence intervals (CIs) for ever use of any vitamins, multivitamins, vitamin A, vitamin C, vitamin E, and calcium, beta carotene, iron, selenium, and zinc supplement were assessed. We further examined frequency, duration and cumulative exposure of each vitamin or mineral when possible. All ORs were adjusted for age, sex, race/ethnicity, study center, education level, pack-years of smoking, frequency of alcohol drinking and fruit/vegetable intake. Results. A decreased risk of HNC was observed with ever use of vitamin C (OR=0.76, 95%CI=0.59-0.96) and with ever use of calcium supplements (OR=0.64, 95%CI=0.42-0.97). There did not appear to be any associations between HNC risk and ever use of any vitamins (OR=0.87, 95%CI=0.71-1.06), multiple vitamins (OR=0.99, 95%CI=0.82-1.19), vitamin A (OR=1.04, 95%CI=0.54-1.98), vitamin E (OR=0.71, 95%CI=0.45-1.11), beta-carotene (OR=1.35, 95%CI=0.65-2.81), iron (OR=0.79, 95%CI=0.54-1.16), selenium (OR=1.21, 95%CI=0.35-4.22) or zinc (OR=0.88, 95%CI=0.34-2.26). Dose-response trends were suggested for years of use of vitamin C (p for trend=0.03) and calcium (p<0.01) with decreasing HNC risk, but not for other vitamin or mineral supplement use. Increased cumulative calcium intake (in tablets) was also associated with decreasing HNC risk (p for trend<0.01). Differences by cancer subsite (oral cavity, pharynx, larynx) were not observed. Conclusions. This is the first time that inverse associations were observed for HNC risk with both vitamin C use and with calcium use in an extremely large sample size. The next steps for our pooled analyses will include adjustment on micronutrients from dietary intake and stratification on HPV infection status where possible. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 2818.

Narrow‐band imaging endoscopy with magnification is useful for detecting metachronous superficial pharyngeal cancer in patients with esophageal squamous cell carcinoma

Head and neck cancers, especially pharyngeal cancers, as well as esophageal cancers frequently coexist either synchronously or metachronously, but most cases of pharyngeal cancer are detected at an advanced stage resulting in poor prognosis. The aim of this study is to evaluate the effectiveness of using narrow-band imaging (NBI) endoscopy with magnification for early detection of pharyngeal cancer on patients following their treatment for esophageal squamous cell carcinoma (SCC). This case series was conducted at the National Cancer Center Hospital in Tokyo between April and October 2005 and included 424 consecutive patients for surveillance endoscopy who had previously undergone chemoradiotherapy (CRT) and/or surgery for esophageal SCC. Observation of the pharyngeal region was randomly conducted on 91 patients using NBI endoscopy with magnification (NBI group) and 333 patients using conventional white light endoscopy (control group). The detection rate for pharyngeal cancer was significantly higher using NBI endoscopy with magnification (10.9%; 10/91) compared with conventional endoscopy (1.2%; 4/333) (P < 0.0001). In particular, the detection rate in CRT patients was significantly higher in the NBI group (12.9%; 7/54) than the control group (0.5%; 1/191) (P < 0.0001). In addition, diagnostic sensitivity, specificity, accuracy, positive predictive value and negative predictive value for the NBI group were 100% (10/10), 97.5% (79/81), 97.8% (89/91), 83.3% (10/12) and 100% (79/79), respectively. NBI endoscopy with magnification is a promising technique for detecting superficial pharyngeal cancer at an early stage in patients previously treated for esophageal SCC.

Pipe smoking and cancers of the upper digestive tract

Pipe smoking has been related to the risk of cancers of the upper digestive and respiratory tract, but quantification of the risk for exclusive pipe smokers is still limited. To analyse the association between exclusive pipe smoking and cancers of the upper digestive tract, we used data from a series of case-control studies conducted in Italy and Switzerland between 1984 and 1999. After excluding cigarette and cigar smokers, 41 male oral and pharyngeal cancer cases, 52 male oesophageal cancer cases and 1,032 male controls were included in the present analysis. Odds ratios (OR) of cancers were estimated by the mean of unconditional multivariate logistic regression, including terms for age, study centre, education, body mass index, and alcohol drinking. Compared to never smokers, exclusive pipe smokers had an OR of 8.7 [95% confidence intervals (CI): 4.0-18.9] of all upper digestive tract cancers. The OR was 12.6 for oral and pharyngeal and 7.2 for oesophageal cancer. Pipe smokers who were also heavy alcohol drinkers had an OR of 38.8 (95% CI: 13.6-110.9) as compared to never smokers and light drinkers. Thus, pipe smoking and heavy alcohol drinking appears to interact at least on a multiplicative model.

No Association between Gastroesophageal Reflux and Cancers of the Larynx and Pharynx

To examine the proposed relation between gastroesophageal reflux disease and cancers of the larynx and pharynx. A cohort of 66,965 patients with discharge diagnoses of heartburn, hiatal hernia, or esophagitis was identified in the Swedish Inpatient Register. We observed a total of 376,622 person-years in the cohort. Identification of laryngeal and pharyngeal cancers was achieved through the Swedish Cancer Register. Standardized incidence ratios, the ratio of the observed to the expected number of cancers, derived from the general Swedish population and adjusted for sex, age, and calendar year, was used to estimate the relative risk. During follow-up, 30 cases of laryngeal and 31 cases of pharyngeal cancer were detected in the cohort. Slightly increased risks of laryngeal [relative risk, 1.6; 95% confidence interval (CI), 1.1-2.2] and pharyngeal carcinomas (relative risk, 1.9; 95% CI, 1.3-2.8) were observed in the total reflux cohort. After stratification to exclude cohort members with a diagnosis of alcoholism, no significant increase in the risk of laryngeal (relative risk, 1.3; 95% CI, 0.8-2.0) or pharyngeal carcinomas (relative risk, 1.0; 95% CI, 0.5-1.6) was found compared with the general population. Furthermore, there were no dose-response patterns of the risk for laryngeal and pharyngeal cancers with years of cohort follow-up, indicators of reflux severity, or specificity of reflux diagnosis. This study provides no evidence in support of the proposed association between gastroesophageal reflux disease and cancers of the larynx or pharynx.

Is the incidence of oral and pharyngeal cancer increasing in Finland? An epidemiological study of 17,383 cases in 1953-1999.

The aim of this study was to describe the occurrence of oral and pharyngeal cancer in Finland over the last half century. The study included all lip, oral and pharyngeal cancer cases diagnosed in Finland and reported to the nation-wide Finnish Cancer Registry between 1953 and 1999. The study comprised 17,383 new cancer cases: 11,666 in males and 5717 in females. Of these, 83% were squamous cell carcinomas. By the end of the study, 1999, the mean age at diagnosis had increased to 63 years for males and 67 for females. The age-adjusted incidence of oral and pharyngeal cancer decreased in males from 12.5 per 10(5) to 8.4 per 10(5) while it increased in females from 3.0 per 10(5) to 3.9 per 10(5). This was because of a decrease in lip cancer incidence in males, while the incidence of tongue, mouth and salivary gland cancers increased in both genders. The annual number of new oral cancer cases increased, however, in both genders. The incidence of lip cancer decreased in males, probably because of a decrease in smoking and in outdoor work. The incidence of intra-oral cancers increased in both genders, possibly because of increased alcohol consumption.

Pharyngeal cancer mortality among chemical plant workers exposed to formaldehyde.

To assess the possible relationship between formaldehyde exposure and mortality risk from pharyngeal cancer (PC), in particular nasopharyngeal cancer (NPC). Subjects were 7328 workers employed at a plastics-producing plant (1941-1984). Vital status for 98% of the cohort and cause of death for 95% of 2872 deaths were determined. Reconstructed exposures to formaldehyde, particulates and pigment were used to compute several exposure measures. Standardized mortality ratios (SMRs) were computed for several demographic, work history and formaldehyde exposure variables. In a nested case-control study, seven cases of NPC and 15 cases of other PC were matched on race, sex, age and year of birth to four controls from the cohort. Among interviewed subjects, lifetime smoking history was determined using respondents or proxies for all but one control subject. Statistically significant 2.23-fold and fivefold excesses for PC and NPC, respectively, were observed. Fivefold range NPC excesses were observed for both short ( < 1 year) and long-term workers and were concentrated among workers hired during 1947-1956. Only three NPC cases were exposed to formaldehyde for longer than one year, and each had low average intensity of formaldehyde exposure (0.03-0.60 ppm). Only a few exposure measures revealed some evidence of an association with all PC or NPC. For all PC combined, adjustment for smoking and year-of-hire in the case-control study generally corroborated findings from the cohort study. Overall, the pattern of findings suggests that the large, persistent nasopharyngeal and other PC excesses observed among the Wallingford workforce are not associated with formaldehyde exposure, and may reflect the influence of nonoccupational risk factors or occupational risk factors associated with employment outside the Wallingford plant.

Familial risk in oral and pharyngeal cancer.

We examined the relationship between a family history of cancer and risk of oral and pharyngeal cancer using epidemiological data from a large case-control investigation of these tumours. 487 (45.7%) of the cases and 485 (41.0%) of the controls reported cancer in a parent or a sibling. After controlling for age, race, sex, study location, respondent status and smoking and alcohol use, the OR associated with any cancer in the family was 1.1 [95% confidence interval (CI) 0.9-1.3]. Risks were non-significantly elevated among those with a history of cancers arising from the oral cavity/pharynx (OR = 1.2, 95% CI 0.7-2.3), oesophagus/larynx (OR = 1.6, 95% CI 0.7-3.8) and lung (OR = 1.2, 95% CI 0.8-1.8), with the excess risk primarily among those for whom a male relative, particularly a brother, was affected with these smoking-related cancers. In addition, an elevated risk of oral/pharynx cancer was found among those whose sisters developed other cancers (OR = 1.6, 95% CI 1.1-2.2). Subsite analyses revealed stronger elevated risks of smoking-related cancers in relatives of pharyngeal cancer cases (OR = 1.7, 95% CI 1.1-2.8) than of oral cancer patients. The data indicate that there is at most a weak familial aggregation of oral/pharynx cancers. Furthermore, since the excess familial risk of oral/pharynx cancer was associated with smoking-related cancers among male but not female relatives, it seems likely that environmental factors (notably smoking and drinking) contribute to the familial tendency observed in this study.(ABSTRACT TRUNCATED AT 250 WORDS)

咽頭癌のＮｄ‐ＹＡＧレーザー治療

We have treated cancer with the CO2 laser since 1980 and have added the Nd-YAG laser treatment since 1983. Twenty hundred and fifty-seven patients with head and neck cancer were treated using the CO2 laser or the Nd-YAG laser. However, we have treated many cancer cases mainly with the contact Nd-YAG laser technique except for laryngeal cancers, because the contact Nd-YAG laser technique can be performed at a low power of 6 to 8 watts in a laser excision of soft tissue with less bleeding and tissue damage, in addition to its high controllability and harmlessness for surgeons or coworkers. Twenty-five cases with mesopharyngeal cancers and 17 cases with hypopharyngeal cancers were treated by this laser surgery.Also, we have recently developed a new ceramic tip for localized laser hyperthermia (laserthermia). It is well known that hyperthermia combined with radio-chemotherapy can be useful in treating malignant tumors. This laserthermia was applied to 26 cases of head and neck malignancies including 4 cases of pharyngeal cancers. Using this treatment with radio-chemotherapy we got complete remission in 5 cases and partial remission in 14 cases.

A case of cancer of the larynx found in mustard gas poisoning

1) A 46-year-old man who had worked during 1941-1945 in a former Japanese army poison gas (chemical weapon) manufacturing factory mainly produced mustard gas, complained of sore throat, swelling of the neck and otalgia since 1962, and was diagnosed as having supraglottic cancer (T4N3M0).Biopsy showed squamous cell carcinoma. The latent period of carcinoma induction was about 21 years.2) The tumor of this case already extended from the left ventricular fold through the left side of epiglottis and aryepiglottic fold to the extrinsic laryngeal muscles. Metastasis was found in the left deep cervical lymph nodes without metastastic markings of the lung. He was treated in 1962 with total larygectomy with left radical neck dissection followed by 6000R. Co60 irradiation.No cervical or distant metastasis has been recognized in 1967.3) This factory was located on the Island of OKU-NO-JIMA, a small island in the Inland sea, Japan. Among these workers, frequent occurrences of laryngeal and bronchogenic cancer were reported by A. YAMADA.4) The carcinogenecity of mustard gas including itsderivatives has been clinically and experimentally confirmed. Accordinng to YAMADA's investigation, 32 consecutive cases were reported-18 cases of bronchogenic cancer, 7 cases of laryngeal cancer, 3 cases of pharyngeal cancer, 3 cases of cancer of the spheniod sinus and one case of cancer of the tongue.5) Eight cases of cancer of the larynx were reported. All cases were male of the average age of 54 year-old, which was younger than that of usual laryngeal cancer. They suffered from excessive cough and expectoration since their engagement in prodution of the mustard gas.The average latent period for carcinoma induction was 19 years and our case was 21 years. The histological type was squamous cell carcinoma.Concerning the sites of the cancer, the site of predilection was the supraglottic region, while only one case was in the subglottic region. In eight cases the glottic cancer was not encountered.6) The incidence of the occupational cancer of the larynx has been very rarely reported. But we believe that these laryngeal cancers observed in the workers having engaged in the production of the mustard gas. are one of the occupational cancer.