Surgical Therapy of T1 and Selected Cases of T2 Glottic Carcinoma: Cordectomy, Horizontal Glottectomy and CO2 Laser Endoscopic Resection

Aims and background

Among the different laryngeal neoplasms, glottic carcinoma is known to be one of the most suitable for functional management. Nevertheless, the best treatment for T1 and T2 glottic carcinoma, whether an open neck procedure, endoscopy or radiotherapy, with reference to recurrence, survival, and functional results, has long been debated.

Study design

From February 1983 to September 1997, 83 patients with well to undifferentiated glottic carcinoma (48 pT1a, 14 pT1b, and 21 selected cases of pT2 with impairment of vocal cord mobility) were submitted to surgery at the Otorhinolaryngologic Section of the Department of Surgical Sciences and Organ Transplantations of Cagliari University. Surgical treatment included 30 laryngofissures with simple or enlarged cordectomy, 22 horizontal glottectomies and 31 endoscopic laser resections. A retrospective review of the records of the patients was performed in order to obtain a better understanding of the outcome of the three different surgical procedures in our institution.

Results

According to the Kaplan-Meier method, the probability of remaining free of local recurrence 3 years after primary surgery was 0.90 for the T1 group and 0.85 for the T2 group. The distribution of recurrences for cordectomy, glottectomy and CO2 laser at 3 years showed a cumulative probability of remaining free of disease after primary surgery of 0.86, 0.85 and 0.88. The probability of remaining free of local recurrence 3 years after salvage surgery was 0.96 for the T1 group and 0.95 for the T2 group. Analyzing the phenomena for type of surgical procedure, local control at 3 years after salvage surgery for cordectomy, glottectomy and exclusive CO2 laser was 0.93, 0.90 and 0.92, respectively. In the endoscopic group, local control rate after any type of salvage therapy modified the percentage at 3 years to 100%. Anterior commissure spread (AC1-AC2) resulted in a difference (not statistically significant) in local control between the group of patients without and with anterior commissure involvement. Laryngeal preservation was achieved in 93.7% (45/48) of patients who survived after salvage surgery following open neck procedures and in 100% of patients originally submitted to the endoscopic approach.

Conclusions

In our experience, although open laryngeal procedures can be still considered a valid option in the treatment of T1 and selected cases of T2 glottic carcinoma, endoscopic laser excision offered an oncologically adequate alternative to the traditional techniques, with minimum discomfort for the patient and satisfactory preliminary functional results.

Revision stapes surgery for recurrent transmissional hearing loss after stapedectomy and stapedotomy for otosclerosis

A total of 20 stapedotomy and 24 stapedectomy cases were retrospectively reviewed to establish the causes of failure, and to evaluate hearing results after revision surgery. Our series included 23 male and 21 female patients. Mean age at revision time was 42 years, and the mean interval from primary surgery and revision stapes surgery was 27 months. The retrospective review of our data, revealed that the most common cause for revision surgery was a displaced prosthesis (47.7%). After revision surgery, the mean post-operative air-bone gap was 14.78 dB. A mean post-operative air-bone gap within 10 dB occurred in 24 patients (54.5%), in 14 patients (31.5%) this was between 11 and 20 dB, in 5 patients (11.5%) between 21 and 30 dB, and in one patient (2.5%) > 30 dB. There were no "dead ears" in this series. Our results compare to other reported series, and confirm that after revision stape surgery, an air-bone gap closure within 10 dB is difficult to obtain. In the present series, the use of the total ossicular replacement prosthesis resulted in the poorest functional hearing results.

Endoscopic revision of failed external dacryocystorhinostomy

Obstruction of the lacrimal pathways is a relatively frequent problem usually corrected by external dacryocystorhinostomy. Failure of the external approach may be due to an inadequate rhinostomy, excessive scar tissue production, anatomical anomalies or concomitant paranasal sinus infectious. The introduction of direct and angled endoscopes for paranasal sinus surgery and the refinement of endoscopic surgical procedures allows a complete intranasal exposure and surgical management of the lacrimal sac, even in cases of recurrent obstruction. The present work offers a retrospective review of the records of seven patients who underwent a revision endoscopic dacriocystorhinostomy (ENDCR) between January 1994 and June 1997 for failed external dacryocystorhinostomy. The preoperative evaluation of the patients, the surgical technique and the postoperative management are examined in detail. A permanent dacryocystorhinostomy was obtained in six patients. One patient underwent a successful bilateral procedure. One patient experienced a persistent stenosis. There were no complications related to the surgical procedure. In our experience the revision endoscopic dacryocystorhinostomy offered several advantages, including a complete exposure of those anatomical anomalies or inflammatory changes of the normal structures that commonly hinder conventional external surgery. Although a larger series will further elucidate the efficacy of this procedure in failed external dacryocystorhinostomy, we recommend considering revision ENDCR as an alternative to the external revision technique.

Polymorphous low-grade adenocarcinoma of the parotid gland

Polymorphous low-grade adenocarcinoma of the salivary glands is a well-defined clinico-pathological entity which occurs almost exclusively in the oral cavity. Only few reports have documented it in the parotid gland. The authors report an additional case of de novo polymorphous low-grade adenocarcinoma of the parotid and describe the histological and immunocytochemical features of the neoplasm. The current literature is also reviewed.

[The immunological assessment of a combined therapeutic approach (chemo- + radiotherapy +/- surgery) including immunotherapy in neoplasms of the head and neck area at an advanced stage]

Fourty-eight patients entered the study, 37 of whom were evaluable, who underwent a nonrandomized combined modality approach plus a randomized immunotherapy treatment assigning the patients to one of the three arms: 1) thymostimulin, 2) beta IFN, 3) thymostimulin + beta IFN. The patients enrollment started in May 1991 and was closed in February 1993: the final evaluation was in February 1994. An immunological evaluation was made for all patients enrolled. The immunological assessment confirms some previous reports, such as the defective proliferative response of PBMC, the high serum level and the low production in culture of soluble IL 2 receptor (s IL 2 R), the low serum level and the low production of IL 2, and moreover shows new data. It is noteworthy that the significant increases--especially for cytokines and s IL 2 R, except for IL 1 alpha which has decreased, both for serum levels and for culture production--are induced by treatment with beta IFN (or with thymostimulin + beta IFN), suggesting that beta IFn is the immunologically effective moiety.

Atypical "reversed" paroxysmal positioning nystagmus in benign paroxysmal positional vertigo

An atypical paroxysmal positioning nystagmus (PPNy), "reversed" in its directional components, is a rare finding in patients suffering from benign paroxysmal positioning vertigo (BPPV). It poses problems of pathophysiogenetic interpretation, differential diagnosis with a CNS lesion and therapeutic strategy. Such a finding was observed in 7 patients (out of a total of 450 BPPV) and took on the typical PPNy pattern after repeated diagnostic manoeuvres. These aspects are incompatible with the "heavy cupula" mechanism (cupulolithiasis) and are better explained by the presence of "free endolymph aggregates" (canalolithiasis) within the posterior semicircular canal (p.s.c). Moreover, canalolithiasis would also permit a more convincing interpretation of all the clinical findings observed in typical p.s.c.-BPPV.

Neo-adjuvant chemotherapy +/- immunotherapy with s.c. IL 2 in advanced squamous cell carcinoma of the head and neck: a pilot study

We carried out a pilot nonrandomized phase II study to compare the neo-adjuvant chemotherapic regimen with cisplatin, 5-FU and vinorelbine with the same combination plus s.c. IL 2 in advanced head and neck squamous cell carcinoma (HNSCC). The primary goals of the trial were to evaluate the feasibility and response rates of the two regimens. The study design consisted of a patient's assignment to either of the two following arms: Arm A: Cisplatin 80 mg/m2 i.v. on day 1; 5-FU 600 mg/m2 i.v. on days 2-5; and vinorelbine 20 mg/m2 i.v. on days 2 and 8, Arm B: the same chemotherapic regimen plus recombinant IL 2 (Proleukin, Eurocetus) 9 MIU s.c. daily from day 9 to 13 and from day 16 to 20 for every cycle. From March 1993 to November 1993 twenty three patients with Stage III-IV HNSCC were enrolled in the study. Patients could be evaluated for response to treatment if they had received at least 2 complete cycles of therapy. The overall response rate (ORR) was 63% in Arm A and 100% in Arm B. The differences for ORR and CR rates were statistically significant in favor of Arm B. The analysis for each of the three drugs included in the chemotherapy schedule shows that both the actually received average dose-intensity and the actually delivered average cumulative doses/patient were higher for Arm B (chemo-plus IL 2 therapy) (approximately 80% of programmed dose-intensity) than for Arm A (approximately 70% of programmed dose-intensity). Both the actually received average dose-intensity and the actually delivered average cumulative doses/patient for IL 2 were more than 80%. In both arms the most frequent side effects were myelosuppression, phlebitis and electrolyte disturbances. There were 2 toxic deaths, 1 in Arm A and 1 in Arm B, both for hematologic toxicity. Our "pilot" study suggests that the combination of cisplatin, 5-FU, vinorelbine plus IL 2 is a highly active, but rather toxic, neo-adjuvant treatment in advanced HNSCC with very high ORR and CR rates.

[Controlled trial of thymostimulin treatment of patients with primary carcinoma of the larynx resected surgically. Immunological and clinical evaluation and therapeutic prospects]

The study aim was that of evaluate the effect of thymostimulin (Tp-1, Serono), either in vitro or in vivo, in patients with primary laryngeal carcinoma, treated only with surgery without any other complementary therapy. Nineteen patients have been studied: nine (mean age 62.5 years, range 48-70) have been treated with Tp-1 and ten patients (mean age 63.4 years, range 56-75) served as "controls". Tp-1 has been administered as follows: 60 mg/m2/daily i.m. days 1-15; 60 mg/m2 twice weekly i.m. days 16-30; 60 mg/m2 once weekly i.m. days 31-60. The treatment was stopped days 61-90. The same cycle was repeated until day 180. The treatment was stopped days 181-365. The following parameters have been assessed: clinical (at the protocol entry and after one year): Performance Status (PF, Karnofsky), local status, presence of relapses, incidence of chronic infections of the upper respiratory tract; immunological in vitro: 1) response to polyclonal mitogens, PHA, Con A and PWM, response to human recombinant Interleukin 2 (rIL 2) of PHA-prestimulated and non prestimulated peripheral blood lymphocytes. The immunological parameters also have been assessed at the protocol entry and after one year. Our results have shown that, in the group of patients treated with Tp-1, 5/9 patients (55.56%) exhibited a significant increase of the PHA response at the end of treatment as compared to pretreatment values, 3/9 (33.34%) showed a decrease and 1/9 (11.10%) an almost unchanged response. In the group of controls, 5/10 (50%) have shown a significant decrease of the response after one year, 3/10 (30%) an increase, 1/10 (10%) were unchanged and 1/10 (10%) exhibited a non univocal response.(ABSTRACT TRUNCATED AT 250 WORDS)

Glucose-6-phosphate dehydrogenase (G6PD) activity in tumoral tissues of G6PD-deficient subjects affected by larynx carcinoma

The activity of glucose-6-phosphate dehydrogenase (G6PD), the key enzyme of the hexose monophosphate (HMP) shunt pathway, was measured in both normal and tumoral larynx tissues from normal and G6PD deficient subjects. Significant increases of this enzymatic activity were found in tumoral tissues of both normal and G6PD deficient subjects, who were characterized by very low levels of G6PD activity in erythrocytes as well as in larynx tissue.

Fine structure of excretory ducts of human salivary glands

Excretory ducts of human major salivary glands are lined by an epithelium consisting of principal cells and by a discontinuous row of basal cells. The principal cells are tall and columnar with mitochondria, large lipofuscin granules and a central nucleus. Just beneath the plasmalemma bordering the lumen, their cytoplasm contains a number of small granules and vesicles similar to those observed in cells of striated ducts. Both in TEM and SEM, these cells also show large apical protrusions devoid of cytoplasmic organelles that may represent a kind of apocrine secretion. The cytoarchitecture of the principal cells seems to be at variance with that of cells of striated ducts. First, the cell body remains unique and does not split into major basal processes. Second, these cells usually lack the long laminated basal folds, housing vertically aligned mitochondria, that are typical of striated ducts. Instead, below the smooth area occupied by the junctional complexes, the lateral cell surfaces are completely covered by a great number of short irregular processes. These organelle-free folds are apparently involved in the mechanism of ion transport since, at their level, there is a strong reactivity for the transporting enzyme K(+)-pNPPase. The basal cells, which are small and cuboidal, have a dense and filamentous cytoplasm. Their functional role is still uncertain.

Survival analysis of 378 surgically treated cases of laryngeal carcinoma in south Sardinia

The effect of various patient and tumor characteristics were evaluated in 378 laryngeal carcinomas treated only surgically between November 1974 and December 1987 at the Ear, Nose and Throat Clinic of Cagliari Medical University in South Sardinia. The overall three-year survival rate was 68%, the five-year survival rate was 61% (approximate 95% confidence interval (CI), 54-68%), and then a plateau seemed to emerge, with the ten-year survival rate being 51%. Tumor ulceration exerted a strong influence on survival: patients with ulcerated tumors had a twofold (95% CI, 1.4-2.9%) higher death rates. Conversely, the influence of tumor site and type of operation was not statistically significant in the multivariate analysis. A median delay in diagnosis of 4 months was found, with 30% of patients reporting an interval longer than 6 months between first symptoms and referral to a physician; overall, however, the influence of delay in diagnosis on survival rate was not significant. Dysphonia seemed to be the symptom less promptly recognized by the patient.

Immunologic assessment determined by response to IL-2 and immunophenotyping of tumor-infiltrating lymphocytes, of invaded and non invaded lymph nodes and of peripheral blood lymphocytes from twenty-one patients with primary laryngeal cancer

The aim of the study was to identify the lymphocyte sets and/or subsets possibly involved in the response to malignant cells. For this purpose we have investigated both the cells at the tumor site, i.e. tumor-infiltrating lymphocytes (TIL), and the cells present in the draining lymph nodes, either invaded or non invaded, as well as the peripheral blood lymphocytes from twenty-one patients with primary laryngeal epidermoid carcinoma. The functional assay was carried out by the proliferative response to mitogens, to Interleukin 2 and to their association, the surface immunophenotyping was performed with a large panel of monoclonal antibodies. TIL are the most responsive cells to mitogens, while the responsiveness of TIL and of LN cells to IL-2 was in the same range. PHA-activated TIL are the most responsive cells to IL-2. Our data indicate that TIL do show in vitro, and probably also in vivo, "activation" with elevated responsiveness to IL-2. The surface phenotype showed a strikingly increased proportion of T8+ cells in TIL as compared to T8+ cells in all types of LN, thus confirming within TIL variable, but high, proportions of clones which display cytolytic activity, possibly induced by IL-2. Our data seem to support the perspective for a therapeutic approach in vivo with IL-2, which via its influence on TIL, may act on tumor cells.

Comparison of nimesulide and flurbiprofen in the treatment of non-infectious acute inflammation of the upper respiratory tract

Sixty patients were enrolled in a controlled randomized single-blind study to compare the efficacy and tolerability of 200 mg/day nimesulide and 300 mg/day flurbiprofen given for 7 days, in the treatment of non-infectious acute inflammation of the upper respiratory tract. Patients were diagnosed as follows: pharyngitis, 20 (33.4%) cases; laryngitis 11 (18.3%) cases; tonsillitis, eight (13.3%) cases; and mixed forms, 21 (35.0%) cases. Both drugs showed the same efficacy in reducing mucosal congestion, local redness, fever and sore throat. Nimesulide treatment gave rise to fewer and less severe side-effects than flurbiprofen treatment.

A histochemical study of the main excretory duct of the human submandibular gland

The duct was reacted histochemically to identify glycoproteins and several enzymic activities. Neutral mucosubstances were detected in the entire cytoplasm of the principal cells, and acid glycoproteins were identified only in a thin apical zone corresponding to the glycocalyx. Lysosomal enzymes were demonstrated as cytoplasmic granules, whereas endogenous peroxidase was diffusely distributed throughout the entire cytoplasm of the epithelial cells. 17 beta- and 3 beta-hydroxysteroid dehydrogenases and prostaglandin-synthetase reactivity were intense in all epithelial cells.

[Collateral effects of 9-alpha-fluor-prednisolone acetate and kanamycin, administered by nasal spray. Clinical experience and experimental data]

Iatrogenic pathology due to treatment with steroid drugs used by systemic route is well known. On the contrary iatrogenic pathology due to topical use of these drugs is rarely reported. Two cases of abuse of 9-alpha- fluor-prednisolone and kanamycin administered by endonasal route are reported. The same treatment has been carried out in patients and rabbits. Clinical and bio-humoral data in patients and anatomo-pathological findings in rabbits are reported. The risks, sometimes underestimated, of an overdose of corticosteroid and antibiotic drugs used by endonasal route are pointed out.

Ciliated cells in the main excretory duct of the submandibular gland in obstructive sialadenitis: a SEM and TEM study

The epithelium of the main excretory duct of the submandibular gland in five cases of obstructive sialadenitis was studied by TEM and SEM. In three cases we found a considerable increase in goblet and ciliated cells. As well as normal cilia, different kinds of ciliary anomalies, especially compound cilia, were noticed. Images of centriole formation and of ciliogenesis, both normal and abnormal, were also observed. Several hypotheses concerning the mode of formation of the compound cilia are discussed.

Histological and ultrastructural findings on mucocele of maxillary sinus

The authors describe a rare case of mucocele of maxillary sinus and, on the basis of the histological and namely of the ultrastructural findings, they maintain that the mucocele has in all probability a multiple pathogenesis being dependent not only on the inflammatory processes, but also on other local predisposing factors and namely the active participation of the mucosa in the formation of the cavity of mucocele.

Cytochemical localization of ouabain-sensitive, K+ -dependent p-nitrophenylphosphatase and Ca++-stimulated adenosine triphosphatase activities in human parotid and submandibular glands

K+ -dependent p-nitrophenylphosphatase (pNPPase) and Ca++ -stimulated adenosine triphosphatase (ATPase) activities were studied in human parotid and submandibular glands using cytochemical methods at the ultrastructural level. In both glands, only the striated-duct epithelium showed K+ -pNPPase reaction product, thereby indicating the localization of Na+, K+ -ATPase. The precipitate was concentrated on the deep invaginations of the basolateral plasma membranes, in close association with their cytoplasmic surface. Ca++ -ATPase activity was also found on the basolateral plasma membranes, but two striking differences from the K+ -pNPPase distribution were observed: firstly, Ca++ -ATPase appeared in both acinar and ductal cells, and secondly, it was localized on the outer side of the plasma membranes.

Human ceruminous glands: a histochemical study

Human ceruminous glands were treated for the histochemical demonstration of glycoproteins and of several enzymatic activities. Neutral mucopolysaccharides were detected in the cytoplasm and pigment granules of the epithelial cells, and acid glycoproteins were recognized only in a thin apical zone corresponding to the glycocalyx. Lysosomal enzymes were demonstrated within cytoplasmic granules, while peroxidase, G6PD and 6PGD showed a diffuse reactivity through the entire cytoplasm of the secretory cells. Age and sex-related differences were observed with respect to 17 beta-HSD and the 3 beta-HSD, whose reactivity appeared more intense in the young and in the female than in the old and in the male glands. Finally, all the ceruminous cells showed a strong prostaglandin synthetase reactivity.

Histochemistry of the 3 beta-hydroxysteroid, 17 beta-hydroxysteroid and 3 alpha-hydroxysteroid dehydrogenases in human salivary glands

Human parotid and submandibular glands showed no 3 alpha-hydroxysteroid dehydrogenase (3 alpha-HSD) activity. The 3 beta-hydroxysteroid dehydrogenase (3 beta-HSD) and the 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) appeared intensely reactive in the duct epithelia of the male and female glands and weakly reactive in the acinar cells of the female ones. The failure to demonstrate 3 alpha-HSD activity indicates that in-vivo androgen activation, if present at all, is not so marked as in target organs. The different distribution of the 3 beta-HSD and 17 beta-HSD in the two sexes can be related not only to the oxidation of androgens but also to the metabolism of the female hormones. Glucose-6-phosphate dehydrogenase (G6PD) and 6-phosphogluconate dehydrogenase (6PGD) do not seem to be specifically influenced by the sex hormones as their pattern of distribution showed no sex differences.

The epithelium of the excretory duct of the human submandibular gland: a transmission and scanning electron microscopic study

The duct of the human submandibular gland (Wharton) is lined by a pseudostratified epithelium consisting of principal and basal cells. Scattered among them are a few goblet and ciliated cells. The principal cells are columnar in shape with many mitochondria, numerous dense bodies and a central nucleus with some indentations. Their apical cytoplasm shows a number of clear vesicles, some of which are reactive to silver and are extruded by exocytosis into the lumen. Other vesicles, which are unreactive, may represent the products of the absorption process. A mechanism of apocrine secretion is also observed in the principal cells. Thus, with regard to its functions, the duct of the human submandibular gland modifies the composition of saliva by adding a secretory component to it. This latter material is derived from the goblet cells but chiefly from merocrine (exocytosis) and apocrine secretion of principal cells.

[Auditory evoked potential in normal rats and after para-chlorophenylalanine (PCPA) treatment]

We have studied the latency behaviour of an early component of the cortical acoustic evoked potentials (EAEP) in albino rats after administration of p-chlorophenylalanine (PCPA), a rather selective tryptophan-hydroxylase inhibitor, at a dose of 100 mg/kg daily for 3 days. The rats were implanted with 3 chronic electrodes: one in the bregma, one in the nasion and 3rd inserted in the periauricular skin. Series of clicks originating from a square pulse of 0.12 msec duration were administrated. Brain responses were amplified by an EEG and averaged by a computer with different post-stimuli analysis times. A first group of 4 rats was tested with clicks of 100 dB (HTL) intensity and brain responses were analysed at 5,10,25,50,100 msec post-stimuli times. Results demonstrate that after PCPA administration there is a latency reduction of EAEP components that have a latency higher than 20 msec. In a second group of 4 rats we have analysed those EAEP components with an intensity of clicks ranging from 60 to 110 dB and results demonstrate that, when PCPA was administered, Latencies of those components were significatively lower than the controls at each stimuli intensity tested. We concluded that 5-HT may influence the acoustic pathways activity and this is according to remarks of other A.A. that found a correlation between acoustic stress and brain 5-HT levels.

Secretory mechanisms of human ceruminous glands: a transmission and scanning electron microscopic study

Two secretory mechanisms (eccrine and apocrine) were observed by transmission and scanning electron microscopy in the same secretory cells of the human ceruminous glands. The eccrine secretion occurs as a typical exocytosis by fusion of the limiting membrane of the secretory granule with the apical plasmalemma. The apocrine secretion is more complex and takes place by sequential steps: bulging of the cellular apex into the lumen, constriction of the projection, and detachment of it from the cell. This mechanism generally causes the removal of the entire projection all at once by decapitation at its base; some variations of this process have been found, however, and are described in the present work. A double membrane, apparently separating the apical protrusion from the rest of the cell, is noticeable in our photographs. Nevertheless, even if this membrane is very similar to a demarcation layer, we consider it as an intercellular double membrane separating two obliquely sectioned cells.

Auditory involvement in thalassemia major

The auditory function of 75 children affected by homozygous beta0-thalassemia, managed with a low transfusion scheme and treated irregularly with low doses of desferrioxamine, and of 75 controls were examined. In 12 patients a mild bilateral conductive hearing impairment due to bony hypertrophy and/or adenoid hypertrophy was found. In 43 cases a moderate monolateral or bilateral sensory-neural hearing loss at high frequencies with recruitment phenomenon was observed. Ferritin levels were determined in a randomly chosen group of these patients with (14) and without heaing loss (11). In the subjects with sensory-neural hearing loss the mean ferritin levels were significantly higher than in those with no hearing defect. There was no obvious relation between sensory-neural damage on the one hand and Hb levels and unit of blood transfused on the other. The results of this study suggest that iron overload could be a cause of damage in the high frequency elements of the auditory mechanism. Intermittent hypoxia and slow 8th nerve compression due to bony hypertrophy as causes of auditory involvement are also discussed.

Ultrastructural localization of endogenous peroxidase in human parotid and submandibular glands

The localization of endogenous peroxidase was studied in human parotid and submandibular glands using the medium of Strum & Karnovsky either at pH 7 or at pH 8.3, after a short fixation of the tissues with a low concentration of glutaraldehyde. At pH 7 reaction product was found in seromucous cells of both glands in the cisternae of the rough endoplasmic reticulum, in the elements of the Golgi apparatus, and in secretory products. However, while in the parotid gland all secretory granules showed peroxidase activity, in the submandibular gland some of the granules were left unstained. At pH 8.3 the pattern of reactivity was practically unchanged in the submandibular gland, whereas the amount of precipitate noticeable in the secretory granules of the parotid gland was greatly reduced. The method of Novikoff et al. for catalase revealed the presence of a number of small bodies having in the characteristics of peroxisomes. Acid phosphatase was not demonstrable in the secretory granules of either parotid or submandibular glands. The lead precipitate indicating enzyme activity was observed only in lysosomes and, occasionally, in the elements of the Golgi apparatus of some sermucous cells.