[Comparison of the clinical features of smear-positive and culture-positive tuberculous patients with smear-negative and culture-positive patients in an education hospital]

The clinical features of 27 smear-positive and culture-positive tuberculous patients (Group 1) were compared with those of 39 smear-negative and culture-positive patients (Group 2) experienced in our hospital. The proportion of the patients who have underlying diseases was lower in Group 1 than Group 2. Ninety-five % of the patients in Group 1 showed positive PPD skin reaction in comparison with 73% of the patients in Group 2. In most of the patients in Group 1, the chest X-ray findings were typical ones for pulmonary tuberculosis, but 36% of the patients in Group 2 showed atypical X-ray findings. Final diagnosis was more difficult for the patients in Group 2 than Group 1. Almost all patients in Group 1 could be diagnosed within a few days and were referred to a tuberculosis hospital for the treatment of tuberculosis. On the contrary, by the patients in Group 2, the final diagnosis was delayed more than one month until the results of culture was available. Also, many patients in this group had underlying disease and only 8 patients could be transferred to a tuberculosis hospital.

[A case report of invasive pulmonary aspergillosis which could not be saved in spite of making an early diagnosis]

A seventy-one year old male with pemphigus vulgaris and treated with steroid therapy for long periods of 7 months was suffered from invasive pulmonary aspergillosis. He complained of a productive cough and the chest X-p indicated a mild infiltration shadow in his both lungfields. He was treated by intravenous antibiotics and no clinical improvement was observed. Two days after the onset of the clinical respiratory symptoms, he was transferred to the division of respiratory diseases and the diagnosis of aspergillosis was confirmed by serological and histopathological studies on the same day. Intravenous amphotericin B and oral itraconazole administrations were started immediately after the diagnosis was made. However, the progression of the disease was so rapid and his immune condition was too weak to respond to the treatment. The overall clinical course of the case was extremely short only 5 days.

[Eight cases of infection caused by the Streptococcus milleri group--significance of serum antibody titer and a comparative investigation of the backgrounds and factors of infections caused by Streptococcus milleri and Streptococcus pneumoniae]

Eight cases of infection caused by Streptococcus milleri were studied clinically, and a comparative study was made of the backgrounds and factors influencing the development of infectious diseases caused by Streptococcus milleri and Streptococcus pneumoniae. The patients (six males and two females) with infectious diseases caused by Streptococcus milleri ranged in age from 21 to 81 years old with an average age of 62.0 years. The infectious diseases encountered among the patients were pyothorax in three patients, and in one patient each pyothorax and lung abscess, pleurisy, a secondary infection of pulmonary emphysema, skin infection related to a tracheostomy, a subdural abscess and a brain abscess, respectively. Six out of the eight cases had infections which formed pus. An underlying disease existed in seven cases, and, in five of these seven cases, it influenced the general condition of these patients. Six serum antibody titers for the S. milleri groups were examined in the First Department of Internal Medicine, University of the Ryukyus. Three cases for S. anginosus, two cases for S. intermedius, and one case for S. constellatus showed high titers of X1024 or X2048. Therefore, the examination of the serum antibody titer seems useful for the diagnosis of infections caused by the S. milleri group. We also carried out a comparative investigation of the backgrounds and factors of infectious diseases caused by S. milleri and S. pneumoniae. There are more underlying diseases in infections caused by S. milleri than in those caused by S. pneumoniae. There were more smokers among the patients with infections caused by S. milleri than among those with S. pneumonia infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Papillary serous carcinoma of the peritoneum in women. A clinicopathologic and immunohistochemical study

BACKGROUND

Papillary serous carcinoma of the peritoneum (PSCP) is a primary peritoneal tumor in women that histologically resembles papillary serous carcinoma of the ovary (PSCO). Recognition of PSCP as an entity is controversial, as is the histogenesis, histopathologic differential diagnosis, and treatment.

METHODS

Ten cases of PSCP retrieved from the pathology files of 4 hospitals in Kyoto and Nara, Japan, were studied clinicopathologically and immunohistochemically.

RESULTS

Patient ages at presentation ranged from 40 to 74 years (median, 56 years). All patients were Asian (Japanese). None of the patients had a history of asbestos exposure. Most of the patients had abdominal swelling, ascites with positive cytology, and elevated serum CA125. At surgery, omental tumors with dissemination to the abdominal and pelvic peritoneum were found in all patients. The histology was similar to that of Grade 2 to 3 PSCO. Immunohistochemical studies using a panel of monoclonal antibodies against carbohydrates showed that Lewis Y is a good marker, in addition to S-100, placental alkaline phosphatase, CA125, and CD15 for separating PSCP from malignant mesothelioma (MM). With cytoreductive surgery and cisplatin-based combination chemotherapy and in some cases adoptive immunotherapy and radiation, a median survival of 27 months and a 5-year survival rate of 27% were attained. One patient with Grade 3 tumor has survived for more than 6 years after surgery.

CONCLUSIONS

(1) Papillary serous carcinoma of the peritoneum is a definite clinicopathologic entity; (2) immunohistochemistry is a useful tool for distinguishing PSCP from MM; (3) cytoreductive surgery and cisplatin-based combination chemotherapy with other adjunct therapies such as immunotherapy and radiation may improve patient survival in PSCP.

[A case of lung cancer with choroidal metastasis]

A 72-year-old woman was admitted to our hospital because of a mass shadow in the left upper lobe on chest roentgenograms. She had noticed floaters in both visual fields 2 months before admission. Percutaneous aspiration of the lung lesion was done, and revealed poorly differentiated squamous cell carcinoma. Metastatic tumors were noted in the choroid of both eyes and in both kidneys. These lesions responded partially to systemic chemotherapy and the floaters disappeared. There have been few reports of metastatic choroidal tumors, but most cite the lung and the breast as the primary sites. We should pay attention to ophthalmologic findings because lung cancer may metastasize to the choroid.

Serial changes of cystic air spaces in fibrosing alveolitis: a CT-pathological study

In patients with cryptogenic fibrosing alveolitis (CFA), subpleural large cysts are sometimes seen within honeycombing on computed tomography (CT). These cysts may be interpreted as bullae and the coexistence of emphysema with CFA might be assumed. We evaluated whether cystic spaces in honeycombing become larger in patients with CFA on serial CT scans. CT scans were obtained in 16 patients with CFA, who had undergone two CT examinations (6 to 43 months, mean 25.1 months apart), were reviewed focusing on the changes in size of the cystic spaces in honeycombing. The mechanism of enlargement of cystic spaces was investigated using microscopic serial sections of autopsied specimens. In 15 of 16 patients, the cystic spaces in honeycombing were larger on the second examination. Histologically, stenosis of bronchioles and slit-like structures between cysts and bronchioles were detected in addition to alveolar septal dissolution and bronchiolectasis. Both the bronchiolar stenosis and the slit-like gaps have the potential to work as check-valves and increase the volume of cystic spaces. Therefore, in the evaluation of CFA, large cysts should be interpreted with caution to avoid misinterpretation of the cysts as bullae associated with emphysema. From the results of this correlative study, we suggest that a check-valve effect is an important mechanism in the formation of large cysts in honeycomb lung.

[Comparison of the prevalence of symptoms, elevated serum antibody, antibody types and complications between two outbreaks of influenza in a ward]

We experienced two outbreaks of influenza in the respiratory ward of our hospital in Feb. 1990 and Feb. 1993. Influenza-like symptoms were recognized in 42 of 67 cases (63%) in 1990, and in 22 of 56 cases (39%) in 1993. In the former outbreak, the prevalence of the serum CF titer for anti-influenza antibody was elevated in 25 of 42 cases (60%) (only the A2 antibody titer in 2 cases, B antibody titer in 4 cases in the latter one). Among asymptomatic inpatients, the serum titer was elevated in 3 of 25 cases (12%) in the former outbreak, but in 1 of 8 cases which the serum CF titer for anti-influenza antibody was measured in the latter one. A respiratory complications secondary to influenza were observed in 6 (2 cases pneumonia, 3 cases lower respiratory tract infection, 1 case asthma attack) of 67 cases during the former period, but only 1 of 56 cases during the latter period. In the two outbreaks of influenza in the respiratory ward we found the same results concerning the occurrence of influenza-like symptoms, an elevation of the serum antibody titer, but a significant difference was noted with regard to the phenotype of the prevalent influenza and the occurrence of complications.

[Bacterial flora of the respiratory tract in patients with long term tracheostomy--colonization of the lower respiratory tract by Pseudomonas aeruginosa]

Throat secretions (TS) and bronchial secretions aspirated from tracheostomy sites (TSTA) from six subjects with long term tracheostomy were simultaneously collected and then cultured every two weeks from January, 1990, to December, 1992. Isolated bacteria were mainly alpha-streptococci (96.2%) and Neisseria (69.6%) in TS, and Pseudomonas aeruginosa (75.7%) in TSTA. In all cases, P. aeruginosa was isolated from and colonization of the lower respiratory tract by this organism was apparent 24.4 months, on average, after tracheostomy. There were ten episodes of respiratory infection in five cases, eight of which occurred after colonization. P. aeruginosa was the causative organism in seven of these episodes. Findings in patients with long term tracheostomy indicated separate colonization of the upper and lower respiratory tracts and that P. aeruginosa colonized the lower respiratory tract. The colonization of the lower respiratory tract by P. aeruginosa would thus appear to be an important factor inducing respiratory infection.

High expression of the Epstein-Barr virus latent protein EB nuclear antigen-2 on pyothorax-associated lymphomas

Pyothorax-associated lymphoma (PAL) is a rare tumor associated with long-standing tuberculous pyothorax. Most of these lymphomas are B-cell lymphomas of high-grade malignancy. Over 50 cases have been reported in Japan, but no cases have been described in Western countries. Its pathogenesis remains unknown. We studied immunohistologically the expression of Epstein-Barr virus- (EBV) encoded latent gene products, EB nuclear antigen-2 and LMP-1, in four cases of PAL. Fifty B-cell lymphomas unrelated to pyothorax, and five EBV-bearing lymphoblastic tumors produced in severe combined immune deficient mice (severe combined immune deficient-EBV+ tumors) were also studied as controls. Marked expression of EB nuclear antigen-2 was demonstrated on all four PALs. LMP-1 was also present in all cases, but both the staining intensity and the number of stained cells remained less than on severe combined immune deficient-EBV+ tumors. Neither EB nuclear antigen-2 nor LMP-1 was observed in the 50 control B-cell lymphomas. Additional molecular genetic analysis revealed that EBVs are incorporated into each PAL clonally. These results confirm the definite association of EBV with PALs, although the significance of weak expression of LMP-1 awaits further study.

The fibrosing process in so-called organized diffuse alveolar damage. An immunohistochemical study of the change from hyaline membrane to membranous fibrosis

On the assumption that some cases of organized diffuse alveolar damage (DAD) result from organization of hyaline membrane, we collected nine autopsy cases of DAD in various stages of the fibrosing process from hyaline membrane to membranous fibrosis and studied changes in the basement membrane and epithelial cells immunohistochemically. In the majority of cases, the following sequence of events was assumed: the hyaline membrane is first formed at the tip of the alveolar septum, a part of the alveolar duct wall where epithelial cells have disappeared. With time it elongates and completely covers alveolar mouths. In the organizing stage, fibroblasts start to permeate through the alveolar duct walls to replace the hyaline membrane completely and to form membranous fibrous tissue. In a few cases, however, fibrous tissue will fill alveolar spaces to form intraluminal diffuse fibrosis. Alveolar epithelial cells and the basement membrane of the alveolar walls are well preserved until the end of the organizing stage when the basement membrane becomes distorted. We believe that membranous fibrosis represents a form of "alveolar duct damage" and that it differs from diffuse fibrosis, which is indicative of diffuse alveolar damage in the true sense.

Comparative study of penetration of lomefloxacin and ceftriaxone into transudative and exudative pleural effusion

We investigated the transpleural penetration of lomefloxacin (LFLX) and ceftriaxone (CTRX). LFLX (200 mg) was administered orally to three patients with transudative fluid and four with exudative fluid, and 2 g of CTRX was administered by drip infusion to four patients with transudative fluid and three with exudative fluid. For both groups that received LFLX and CTRX, blood samples were drawn at time zero and 1, 2, and 6 h after drug administration. Thoracocentesis of each group was performed at 6 h after drug administration. The mean ratios of concentrations in pleural fluid/maximum concentrations in serum (P/S max) of LFLX were 66% in patients with transudative fluid and 69% in patients with exudative fluid. The mean ratios of P/S max of CTRX were 9.1% in patients with transudative fluid and 13.5% in patients with exudative fluid. The P/S max ratios for the penetration of LFLX were five to six times higher than those for CTRX. In addition, there was less differentiation in concentrations of LFLX in pleural fluid between the transudative and exudative effusions than there was in the concentrations of CTRX.

[A case of so-called carcinosarcoma of the lung]

A 65-year-old male was admitted to our institute because of bloody sputum. A tumor in right S6 was detected by X-ray, CT and MRI. Bronchoscopic study showed that the right lower bronchus was occluded by the tumor, in which non-epithelial malignant cells were detected. Therefore right bilobectomy was performed. This tumor was a pedunculated endobronchial type measuring 6 x 4 x 3cm. Histologically, the tumor presented carcinomatous (squamous cell carcinoma and adenocarcinoma) and sarcomatous elements. Immunohistologically, many malignant cells were positively stained by vimentin and muscle-actin, which suggested differentiation from muscle components.

[Study of the duration of antimicrobial chemotherapy in mycoplasmal pneumonia]

We assessed the period of administration of antibiotics required for cases of mycoplasmal pneumonia. The subjects were 38 patients with mycoplasmal pneumonia admitted to our hospital. These patients were treated with 100 mg minocycline or 500 mg erythromycin by intravenous infusion twice a day. They were divided into a 6 day-administration group (Group A; 16 cases) and a 9 day-administration group (Group B; 17 cases). Administration was discontinued on the 4th day or earlier in 5 cases due to side effects. A comparative assessment was made between Groups A and B with respect to body temperature, WBC, erythrocyte sedimentation rate, CRP, and chest X-ray on the 3rd, 6th, and 9th days of treatment, but no significant difference was observed. Residual shadows at the end of treatment were present in 100% of Group A and in 47% of Group B, but they disappeared gradually in both groups. No cases of recurrence were observed in either Group A or B within 1 month after the completion of treatment. Regarding the treatment period for mycoplasmal pneumonia by intravenous infusion of minocycline or erythromycin, no significant clinical difference was observed between the 6 day-administration group and the 9 day-administration group, suggesting that 6 days of administration is sufficient for treatment.

Follicular center cell lymphoma of childhood in Japan

Following a histologic review of 108 patients with childhood lymphoma from 20 hospitals in the Osaka, Hyogo, Nara, and Kyoto prefectures of Japan during the period 1964-1989, 16 cases (15%) were classified as follicular center cell (FCC) lymphomas. None had a follicular pattern of proliferation. The age range was from 2 to 15 years (median 10) with no peak incidence. The male/female ratio was 1.3:1. Presentation was nodal in 10 patients and extranodal in 6. Chronic infection and other predisposing factors for the development of FCC lymphomas in childhood are discussed, with a review of the literature.

[Investigation of 5-fluorouracil (5-FU) levels and pyrimidine nucleoside phosphorylase activities in the tissues from patients with uterine cervical and ovarian cancers after oral administration of 5'-DFUR]

The usefulness of 5'-DFUR in both patients with uterine cervical and ovarian cancers was investigated by determining pyrimidine nucleoside phosphorylase (PyNPase) activities and 5-FU levels in cancerous and normal tissues resected from them after oral administration of 5'-DFUR. In uterine cervical cancer, each group of 9 cases administered single dose of 400 mg of 5'-DFUR and 7 cases administered 400 mg of 5'-DFUR 3 times a day continuously for 7 days was investigated. In ovarian cancer, all of 9 cases were administered 400 mg of 5'-DFUR 3 times a day continuously for 7 days. In conclusion, PyNPase activities in the tissues of uterine cervical and ovarian cancers were higher than those in the normal tissues. 5-FU tissue levels in the cancerous tissues were significantly higher than in the normal tissues and blood as well. This tendency was observed in each of the single and continuous administration groups. These results suggest that the tumor selectivity which is one of characteristics of 5'-DFUR could be expected also for cancer in the field of gynecology.

[Clinicopathological study of methicillin-resistant Staphylococcus aureus detected by pulmonary microbial culture in autopsied cases]

Microbial culture of lung specimens from 569 autopsied cases from 1986 to 1989 revealed methicillin-resistant Staphylococcus aureus (MRSA) in 28 cases, which were subsequently analyzed clinicopathologically. The number of MRSA positive cases has markedly increased in recent years (2 cases in 1986, 2 in 1987, 6 in 1988, 18 in 1989). The most frequent underlying disease was neoplasm, which was seen in 17 cases. Of non-neoplastic diseases, liver cirrhosis and diffuse panbronchiolitis were prevalent. Twenty-four cases had received a course of antibiotic therapy. Antibiotics frequently administered were third-generation Cephem and Imipenem/cilastatin sodium (used in 20 cases). Antibiotics o which MRSA was sensitive were administered in only one case (minocycline). Sputum culture was performed in only 10 cases, 5 of which were MRSA positive. MRSA had acquired resistance to fosfomycin and ofloxacin. Histological examination revealed complication by pneumonia in 19 cases. In 7 of these 19 cases, MRSA was the only pathogen detected. Pulmonary MRSA infection detected at autopsy is frequently seen in patients with terminal stage cancer, but it is frequently not diagnosed and is undertreated. This may be a factor responsible for the recent marked increase in the proportion of MRSA in pathogens causing infection within medical institutions.

[Etiological examination of idiopathic interstitial pneumonia and lung cancer in autopsy cases]

In order to investigate the etiology of usual interstitial pneumonia (UIP) and UIP with lung cancer (LC), autopsy findings in 18 cases of UIP with LC and 11 cases of uncomplicated UIP were clinicopathologically compared with the environmental factors of smoking habits and occupation. UIP with LC was highly correlated with smoking, especially heavy smoking and with occupations in which dust is inhaled, such as electrical installation and ceramic production, indicating that these environmental factors are important background factors in the complication of UIP with IC. Pathologic examination of cases of UIP with LC (6 squamous cell carcinomas, 5 small cell carcinomas, 4 adenocarcinomas, and 3 large cell carcinomas, 2 of which showed pulmonary double carcinoma revealing a slight correlation between fibrosis and primary site of LC and a slightly greater correlation of squamous cell carcinoma and small cell carcinoma to smoking habits and inhalation of dust. In terms of the correlation between UIP and LC among autopsy cases, the environmental factors proved to be more significant than the fibrotic findings. These environmental factors are thought to merit consideration as common predisposing factors in the development of LC and its complication with UIP.

Lymphoproliferative diseases of the lung in Japan: review of thirty-six patients with an immunohistochemical study

Thirty-six cases of primary lymphoproliferative disease of the lung, collected from hospitals in Japan, have been reviewed. Histologically they were divided into three groups: definite lymphoma (DL) showing monomorphous proliferation of medium to large cells (17 cases), small lymphoid cell proliferation (SLP) frequently containing lymphoid follicles (11 cases), and pseudolymphoma showing lymphoid follicular hyperplasia (LFH) (six cases) or mixed diffuse infiltration of small lymphocytes and macrophages (two cases). In some DL cases, lymphoid follicles were present in or near the tumors. Pulmonary lesions in SLP and LFH patients were frequently detected at their medical checkups. Immunohistochemistry revealed that proliferating cells in 15 out of 17 DL and all SLP cases were B cells with restricted expression of the immunoglobulin light chain, all lambda type, in three DL and four SLP cases. From morphologic and immunologic findings, 10 SLP cases were diagnosed as intermediate lymphocytic lymphoma (ILL) and one as being of lymphoplasmacytic type. Two DL cases with convoluted nuclei proved from immunohistochemistry to be of T-cell type, showing a much lower frequency of T-cell type than that found in the USA (approximately 50%).

[Clinicopathological features of metastatic pulmonary calcinosis with malignant neoplasm]

Metastatic pulmonary calcinosis is a rare complication seen in malignancies accompanied by hypercalcemia, or chronic renal failure. We reviewed the clinicopathological findings of 8 cases of metastatic pulmonary calcinosis accompanied malignancy revealed at autopsy. The underlying diseases were malignant lymphoma in 3 cases (adult T cell lymphoma in 2 cases), multiple myeloma in 2, lung cancer in 2, and acute myelocytic leukemia in 1, all cases were complicated by hypercalcemia and renal failure. Chest X-ray revealed almost normal findings in 2 cases, bilateral diffuse infiltrates in 4, bilateral infiltrates in the apex in 1, and right atelectasis in 1. Bone scintigraphy was performed in 4 cases, and revealed warm pulmonary uptake in 1 patient with multiple myeloma and 1 with lung cancer, but normal findings in the 2 other cases. Histopathological examination revealed diffuse alveolar septal edema and fibrosis due to calcium deposition, which were considered to be the cause of respiratory failure. Metastatic pulmonary calcinosis is a rare but a serious complication in malignancies accompanied by hypercalcemia and renal failure, and bone scintigraphy seems to be a useful method for its diagnosis.

[Cellular interstitial pneumonia and follicular bronchiolitis diagnosed by open lung biopsy in a patient with rheumatoid arthritis]

A 54-year-old woman under treatment for rheumatoid arthritis was admitted because of aggravation of dyspnea on effort and restrictive pulmonary dysfunction. Although chest X-ray revealed no marked change, the symptoms progressively worsened, necessitating open lung biopsy for diagnosis and treatment. Based on the histopathological findings of the biopsied tissue, the patient was diagnosed as having active rheumatoid lung complicated with cellular interstitial pneumonia and follicular bronchiolitis. The patient responded well to adrenocorticosteroid and immunosuppressor therapy, and is now being followed up as an outpatient. Rheumatoid arthritis can be complicated by diverse lung diseases. Among them one important disease is interstitial pneumonia, which serves as a prognostic factor. When cellular interstitial pneumonia is treated with adrenocorticosteroid therapy, it responds well and its prognosis is good. Therefore, its early detection and appropriate adrenocortical therapy are essential. Patients with rheumatoid arthritis presenting with dyspnea on effort and pulmonary dysfunction should be examined for cellular interstitial pneumonia, follicular bronchiolitis and other lung diseases, even when no marked change is visible on chest X-ray films.

Pallido-nigro-luysian atrophy, progressive supranuclear palsy and adult onset Hallervorden-Spatz disease: a case of akinesia as a predominant feature of parkinsonism

Few parkinsonian patients present with 'pure akinesia' or with severe akinesia accompanied by only mild rigidity, tremor and other manifestations such as ophthalmoplegia. Pathological examinations of such cases have rarely been conducted and have revealed findings compatible with progressive supranuclear palsy (PSP), pallido-nigro-luysian atrophy (PNLA) or Parkinson's disease. We report a parkinsonian patient whose main clinical feature was akinesia. A postmortem study of this patient showed findings corresponding to PNLA and PSP. Histochemical properties of the pallidal pigment granules were equivalent to those of Hallervorden-Spatz disease (HSD) and striatonigral degeneration. In addition to iron-positive pigment granules, spheroids, severe neuronal loss and gliosis in the globus pallidus and substantia nigra, formation of Alzheimer's neurofibrillary tangle (NFT) in the brainstem shares characteristics with PSP, adult onset HSD and PNLA. We suggest that the underlying pathology of 'pure' akinesia is most often situated in the globus pallidus substantia nigra and subthalamus (Luys), and that PSP, PNLA and adult onset HSD may constitute a spectrum of one disease.

Angiotropic lymphoma with histologic features of neoplastic angioendotheliomatosis presenting with predominant respiratory and hematologic manifestations. Report of a case and review of the literature [corrected]

Neoplastic angioendotheliomatosis (NAE) is a rare fatal disease characterized by widespread intravascular proliferations of neoplastic mononuclear cells. Clinically, dermatologic and bizarre neurologic manifestations usually predominate. The origin of the neoplastic cells remains still undetermined. The authors report a patient with NAE peculiar with respect to the following points: (1) the patient predominantly manifested respiratory symptoms and hematologic findings and lacked cutaneous or neurologic manifestations; and (2) immunohistochemical and molecular genetic studies showed the B-cell nature of the neoplastic cells, although previous cases with predominant respiratory or hematologic manifestations were reported to be of endothelial origin. Despite the rarity, this type of NAE or angiotropic [corrected] lymphoma should be recognized because it is easily confused with other disorders, particularly vasculitis or thrombotic thrombocytopenic purpura.

Extranodal non-Hodgkin's lymphoma of the head and neck. A clinicopathologic study in the Kyoto-Nara area of Japan

The clinicopathologic features of 114 Japanese patients with extranodal non-Hodgkin's lymphoma of the head and neck region were analyzed. The median age was 60.5 years and the male:female ratio was 1.5:1. The most common site of involvement was Waldeyer's ring, followed by the oral cavity, thyroid gland, paranasal sinuses, nasal cavity, and larynx. Seventy-five percent of the patients were in Stage I or Stage II at admission. Histologically, diffuse lymphoma accounted for 94% and follicular lymphoma for 6% of cases. The histologic grade according to the Working Formulation System of the National Cancer Institute was low in 11%, intermediate in 75%, and high in 14% of cases. Immunohistochemical study showed that the majority of the cases were of B-cell type and only 13 cases (11%) were of the T-cell type. Peripheral T-cell lymphomas (eight cases) mainly occurred in the nasopharynx and nasal cavity, whereas four of five thymic T-cell lymphomas were found in the palatine tonsil. The over-all 5-year survival rate was 54%, and the factors affecting survival were sex, histologic grade, T/B phenotype, clinical stage, and the site of initial presentation. Five-year survival with nasal cavity and Waldeyer's ring lymphoma was 24% and 46%, respectively. The poor prognosis of lymphomas at these sites might result from the predominance of T-cell lymphoma, the paucity of low grade lymphoma, and the relatively high incidence of cases that were in an advanced stage at presentation. In Stage II, patients treated with combined therapy tended to have a better 5-year survival rate than those treated with radiotherapy alone.