Real-World Treatment Patterns of Older Adults with Locally Advanced SCCHN Using SEER-Medicare

PURPOSE/OBJECTIVE(S)

Roughly 50-67% of patients with squamous cell carcinomas of the head and neck (SCCHN) present with locally advanced (LA) disease and 65% of them relapse after initial therapy. The standard of care for LA SCCHN is definitive therapy (DT), a combination of surgery and or radiation therapy (RT), with or without platinum-based chemotherapy/cetuximab (chemo), that has been shown to optimize long term disease control. Few published analyses have characterized recent real-world treatment (Tx) patterns of older adults with LA SCCHN in the US.

MATERIALS/METHODS

We used the Surveillance, Epidemiology, and End Results (SEER)-Medicare database, a linkage of cancer registry and claims data, to identify patients diagnosed with LA SCCHN (first and only cancer) from 2010 to 2017 who initiated a relevant Tx (Tx initiation date defined as index date) and were continuously enrolled in Medicare Parts A, B, and D from 12 months pre-index until death or 12 months post-index. We used clinical guidelines regarding timing and frequency of treatments to build an algorithm that used Medicare claims to categorize initial Tx as non-DT, non-surgical DT (concomitant chemo+RT (cCRT) or chemotherapy before RT/cCRT), or surgical DT (surgery then RT/cCRT ± prior chemo).

RESULTS

We identified 1052 older adults with LA SCCHN (median age 73 years, 37% female, and 81% non-Hispanic white) whose initial treatment was started a median of 26 days after initial diagnosis. Of the 610 patients who received a DT as their initial Tx, 23.3% of patients had a subsequent Tx: 3.8% received immunotherapy-containing regimens (IO), and the most common subsequent Tx were surgery only (7.7%), chemotherapy only (3.6%), and RT only (3.4%). The median time to next Tx (TTNT) differed by DT category and primary tumor site. (Table 1) CONCLUSION: In this descriptive analysis, we provided an update on the Tx patterns of older adults with LA SCCHN in the US, for whom there have been no novel FDA approvals in over a decade. We found that a large proportion (42%) of patients did not receive DT regimens in the real-world setting despite known benefits in LA SCCHN. Roughly a quarter of patients required subsequent Tx. Availability of IO was low due to approvals after 2017. These findings suggest a need for novel therapies that can improve outcomes in LA SCCHN.

Racial Disparities in Survival of Patients with High-Risk LA SCCHN in the U.S

PURPOSE/OBJECTIVE(S)

Approximately 50-67% of patients with squamous cell carcinomas of the head and neck (SCCHN) present with locally advanced (LA) disease. Human papillomavirus (HPV) associated SCCHN has improved survival compared to non-HPV SCCHN. Studies have analyzed racial disparities in LA SCCHN but few have adjusted for HPV status and socio-economic status (SES). Our objective was to characterize disparities in LA SCCHN.

MATERIALS/METHODS

We identified high-risk patients from 2010-2017 with AJCC v8 Stage IVA/IVB SCCHN of the oral cavity, oropharynx (OP), larynx or hypopharynx, or Stage III SCCHN of the OP in the Surveillance, Epidemiology, and End Results (SEER) with HPV Status and Census Tract-level SES/Rurality Combined Database. We excluded OP patients with missing HPV data. SEER-reported treatment was used to classify initial treatment as definitive therapy (DT) categories: surgical DT, non-surgical DT or non-DT. The Kaplan Meier method was used to estimate overall survival (OS) with 95% confidence intervals (CI). Multivariable cox proportional hazard models were used for associations between covariates and hazard ratio (HR) of death, adjusted for age, sex, race, ethnicity, DT category, marital status, rurality, tumor size, cancer stage, and HPV status. We explored the impact of additionally adjusting for Yost SES index quintiles.

RESULTS

We identified 17,818 eligible patients: 79.3% White, 14.4% Black, 5.8% Asian/Pacific Islander (A/PI), and 0.6% American Indian/Alaska Native (AI/AN). Primary tumor sites were oral cavity (36.8%), larynx (29.0%), OP (24.4%), and hypopharynx (9.9%). 10.4% were HPV-associated. Race and SES quintiles were related (chi-squared, p<0.001) and the majority (56.5%) of black patients were in the lowest SES quintile. mOS was shorter and risk of death was significantly higher for black vs white patients in both the all-site and OP-only cohorts. When we added SES to multivariable analyses, Black race was no longer associated with increased risk of death in the all-site or OP-only cohorts. (Table 1) CONCLUSION: We found that when adjusting for sociodemographic and clinical factors, Black race was independently associated with a higher risk of death compared to white patients. When we adjusted for SES in multivariable analysis the association between Black race and risk of death was no longer significant, consistent with previously published analyses and indicative of a complex relationship between race and SES. Further research is needed to identify and address the causative factors of disparities in LA HNSCC.

4D CT angiography more closely defines intracranial thrombus burden than single-phase CT angiography

BACKGROUND AND PURPOSE

In patients with acute stroke, the location and extent of intravascular thrombi correlate with clinical and imaging outcomes and have been used to predict the success of intravenous thrombolysis. We hypothesized that 4D-CTA reconstructed from whole-brain CTP more closely outlines intracranial thrombi than conventional single-phase CTA.

MATERIALS AND METHODS

Sixty-seven patients with anterior circulation occlusion were retrospectively analyzed. For 4D-CTA, temporal maximum intensity projections were calculated that combine all 30 spiral scans of the CTP examination through temporal fusion. Thrombus extent was assessed by a semi-quantitative clot burden score (0-10; in which 0 = complete unilateral anterior circulation occlusion and 10 = patent vasculature). In patients with sufficient collateral flow, the length of the filling defect and corresponding hyperdense middle cerebral artery sign on NCCT were measured.

RESULTS

Clot burden on temporal maximum intensity projection (median clot burden score, 7.0; interquartile range, 5.1-8.0) was significantly lower than on single-phase CT angiography (median, 6.0; interquartile range, 4.5-7.0; P < .0001). The length of the hyperdense middle cerebral artery sign (14.30 ± 5.93 mm) showed excellent correlation with the filling defect in the middle cerebral artery on temporal maximum intensity projection (13.40 ± 6.40 mm); this filling defect was larger on single-phase CT angiography (18.08 ± 6.54 mm; P = .043).

CONCLUSIONS

As the result of an increased sensitivity for collateral flow, 4D-CTA temporal maximum intensity projection more closely outlines intracranial thrombi than conventional single-phase CT angiography. Our findings can be helpful when planning acute neurointervention. Further research is necessary to validate our data and assess the use of 4D-CTA in predicting response to different recanalization strategies.

The double-spouted loop ileostomy

OBJECTIVE

A functional improvement to a conventional loop ileostomy is described with both proximal and distal limbs spouted reducing the number of patients with problematic ileostomies.

METHOD

The results of the National Prospective Audit of Stoma Complications for the hospital showed 14/15 of the traditional single loop ileostomies were identified as problematic. 21 patients were then studied prospectively, who underwent formation of a new type of loop stoma, in which both the proximal and distal limbs were spouted.

RESULTS

In the group of 21 patients with a double spouted loop ileostomy 3/21 had a problematic stoma. The number of appliances needed was significantly less than the single spouted group. The number of home visits by the stoma nurse and outpatient visits to the stoma therapy team at the hospital were also significantly less in the double spouted group.

CONCLUSION

This modification of the loop ileostomy, with both the proximal and distal ends of the bowel spouted has several advantages. The danger of spouting the wrong limb is eliminated, it can be created very easily via a trephine technique and spouting the distal limb reduces the leakage of mucus under the flange of the stoma bag, reducing the problems of poor appliance adhesion.

Identification and characterization of two neurogenic zones in interface organotypic hippocampal slice cultures

Neurogenesis plays a role in many physiological (memory formation) and pathological (stroke, depression) processes. However the mechanisms of postnatal stem cell proliferation and neurogenesis are still poorly understood. We characterized early neurogenesis in vitro in rat organotypic hippocampal slice cultures. Proliferation was assessed by bromodeoxyuridine incorporation, neurogenesis by bromodeoxyuridine-double labeling with doublecortin or beta-III tubulin. We showed for the first time that in addition to the dentate gyrus organotypic hippocampal slice cultures include a second neurogenic zone: the posterior periventricle, which is a part of the lateral ventricle wall. This structure lining the stratum oriens contained Nestin+ precursors. We could identify morphological and functional differences between dentate gyrus and posterior periventricle precursor populations. Our data demonstrate that basic fibroblast growth factor treatment induced a fast but short-lasting neurogenic response in the dentate gyrus while the posterior periventricle showed a more pronounced and long lasting neurogenic effect of basic fibroblast growth factor. Thus two neurogenic zones with different neurogenic properties were identified in organotypic hippocampal slice cultures.

Submicrometer position control of single trapped neutral atoms

We optically detect the positions of single neutral cesium atoms stored in a standing wave dipole trap with a subwavelength resolution of 143 nm rms. The distance between two simultaneously trapped atoms is measured with an even higher precision of 36 nm rms. We resolve the discreteness of the interatomic distances due to the 532 nm spatial period of the standing wave potential and infer the exact number of trapping potential wells separating the atoms. Finally, combining an initial position detection with a controlled transport, we place single atoms at a predetermined position along the trap axis to within 300 nm rms.

Neutral atom quantum register

We demonstrate the realization of a quantum register using a string of single neutral atoms which are trapped in an optical dipole trap. The atoms are selectively and coherently manipulated in a magnetic field gradient using microwave radiation. Our addressing scheme operates with a high spatial resolution, and qubit rotations on individual atoms are performed with 99% contrast. In a final readout operation we analyze each individual atomic state. Finally, we have measured the coherence time and identified the predominant dephasing mechanism for our register.

Expression and purification of turkey coronavirus nucleocapsid protein in Escherichia coli

Purification of turkey coronavirus (TCoV) nucleocapsid (N) protein, expressed in a prokaryotic expression system as histidine-tagged fusion protein is demonstrated in the present study. Turkey coronavirus was partially purified from infected intestine of turkey embryo by sucrose gradient ultracentrifugation and RNA was extracted. The N protein gene was amplified from the extracted RNA by reverse transcription-polymerase chain reaction and cloned. The recombinant expression construct (pTri-N) was identified by polymerase chain reaction and sequencing analysis. Expression of histidine-tagged fusion N protein with a molecular mass of 57 kd was determined by Western blotting analysis. By chromatography on nickel-agarose column, the expressed N protein was purified to near homogeneity as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. The protein recovery could be 2.5 mg from 100 ml of bacterial culture. The purified N protein was recognized by antibody to TCoV in Western blotting assay. The capability of the recombinant N protein to differentiate positive serum of turkey infected with TCoV from normal turkey serum was evident in enzyme-linked immunosorbent assays (ELISA). These results indicated that the expressed N protein is a superior source of TCoV antigen for development of antibody-capture ELISA for detection of antibodies to TCoV.

Continued imaging of the transport of a single neutral atom

We have continuously imaged the controlled motion of a single atom as well as of a small number of distinguishable atoms with observation times exceeding one minute. The Cesium atoms are confined to potential wells of a standing wave optical dipole trap which allows to transport them over macroscopic distances. The atoms are imaged by an intensified CCD camera, and spatial resolution near the diffraction limit is obtained.

Coherence properties and quantum state transportation in an optical conveyor belt

We have prepared and detected quantum coherences of trapped cesium atoms with long dephasing times. Controlled transport by an "optical conveyor belt" over macroscopic distances preserves the atomic coherence with slight reduction of coherence time. The limiting dephasing effects are experimentally identified, and we present an analytical model of the reversible and irreversible dephasing mechanisms. Our experimental methods are applicable at the single-atom level. Coherent quantum bit operations along with quantum state transport open the route towards a "quantum shift register" of individual neutral atoms.

Specific mucosal IgA immunity in turkey poults infected with turkey coronavirus

The objective of this study was to elucidate the kinetics and magnitudes of specific IgA antibody responses in intestines of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 days of age. Intestinal segment cultures were administered for duodenum, jejunum, and ileum and the IgA antibody responses were analyzed at 1, 2, 3, 4, 6, or 9 weeks post-infection (PI) in two different experiments. The kinetics of virus-specific IgA antibody responses in duodenum, jejunum, and ileum were similar: gradually increased from 1 week PI, reached the peak at 3 or 4 weeks PI, and declined afterward. The virus-specific IgA antibody responses in duodenum, jejunum, and ileum showed negative correlation with duration of TCV antigen in the corresponding locations of intestine with Spearman's correlation coefficient of -0.85 (p=0.034), -0.74 (p=0.096), and -0.75 (p=0.084), respectively. Moreover, the virus-specific IgA antibody responses in serum were positively correlated with that of duodenum (coefficient=0.829, p=0.042), jejunum (coefficient=0.829, p=0.042), and ileum (coefficient=0.771, p=0.072) segment cultures, suggesting that the induction of specific IgA response in serum was predictive of an IgA response in intestine. The results indicate that intestinal mucosal IgA antibodies to TCV are elicited in turkeys following infection with TCV. The local mucosal antibodies may provide protective immunity for infected turkeys to recover from TCV infection.

Purification of turkey coronavirus by Sephacryl size-exclusion chromatography

Sephacryl S-1000 size-exclusion chromatography was used to purify turkey coronavirus (TCoV) from infected turkey embryo. TCoV was propagated in the 22-day-old turkey embryos. Intestines and intestinal contents of infected embryos were harvested and homogenized. After low speed centrifugation, the supernatant was concentrated by ultracentrifugation through a cushion of 30 or 60% sucrose solution, or by ammonium sulfate precipitation. The purification methods included sucrose gradient and Sephacryl S-1000 size-exclusion chromatography. Ultracentrifugation through a cushion of 60% sucrose solution was better than the other two methods for concentration of TCoV from intestinal homogenate. The most effective method for purifying TCoV and removing extraneous materials was size-exclusion chromatography as analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. More spike-rich particles were observed in the sample purified by chromatography than those purified by sucrose gradient as examined by electron microscopy. Differentiation of turkey anti-TCoV antiserum from normal turkey serum was better achieved by ELISA plates coated with TCoV preparation purified by size-exclusion chromatography than that purified by sucrose density gradient. The results indicated that Sephacryl S-1000 chromatography was useful for purification of TCoV.

Humoral and cellular immune responses in turkey poults infected with turkey coronavirus

The objective of the present study was to elucidate the kinetics of humoral and cellular immune responses of turkey poults infected with turkey coronavirus (TCV). Turkey poults were orally inoculated with TCV at 10 d of age, and the immune responses were analyzed at 1, 3, 7, 14, 21, 28, 42, and 63 d postinfection (PI) in three different experiments. Total Ig to TCV was initially detected at 7 and 14 d PI in Experiments 1 and 3. In addition, Ig gradually increased from 7 to 21 d PI and remained at 80 immunofluroescent antibody assay (IFA) titers or more thereafter. Lymphocyte proliferation responses of spleen cells to concanavalin A were higher in TCV-infected turkeys than in noninfected control turkeys with significant differences (P < 0.05) being noted at 14 and 63 d PI in Experiment 2 and at 3 and 28 d PI in Experiment 3. Strong IFA staining response to TCV antigen was observed in intestines of turkeys at 1, 3, and 7 d PI, and the response declined from 14 to 28 d PI in Experiment 3. In Experiment 3, the IgG isotype antibody response to TCV was markedly increased after 21 d PI and remained high until 63 d PI. The IgM isotype antibody response to TCV was 1.40 and 0.91 at 7 and 14 d PI, respectively. The IgA isotype antibody response to TCV was very low as detected at 7 (0.13), 14 (0.20), and 21 (0.17) d PI. Turkeys infected with TCV had significantly higher (P < 0.05) antibody response to sheep erythrocytes than noninfected controls at 7 d PI. Virus-specific lymphocyte proliferation response of spleen cells was significantly stimulated (P < 0.05) at 63 d PI in Experiment 3. The proportion of the CD4+ subpopulation of T lymphocytes was significantly increased (P < 0.05) at 1, 7, and 21 d PI in Experiment 3. The results indicate that humoral and cellular immunities to TCV are elicited in turkeys following infection with TCV.

Deterministic delivery of a single atom

We report the realization of a deterministic source of single atoms. A standing-wave dipole trap is loaded with one or any desired number of cold cesium atoms from a magneto-optical trap. By controlling the motion of the standing wave, we adiabatically transport the atom with submicrometer precision over macroscopic distances on the order of a centimeter. The displaced atom is observed directly in the dipole trap by fluorescence detection. The trapping field can also be accelerated to eject a single atom into free flight with well-defined velocities.

Nucleocapsid protein gene sequence analysis reveals close genomic relationship between turkey coronavirus and avian infectious bronchitis virus

Antibodies to infectious bronchitis virus (IBV) cross-react with turkey coronavirus (TCV) in immunofluorescence assay (IFA) indicating that IBV and TCV may share an amino acid sequence similarity. To determine its extent, the gene encoding the nucleocapsid (N) protein of TCV was amplified by reverse transcription-PCR (RT-PCR) from RNA purified from intestines of embryos of turkeys infected with various TCV isolates and from allantoic fluid of chicken embryos infected with IBV M41 strain, the obtained N genes were cloned, sequenced and compared with known sequences of N genes of five IBV strains. The primers for amplification were designed from the genome of IBV PCR products were obtained only from two of eight TCV isolates tested. It was found that the two TCV isolates were identical with five IBV strains by 90.1-94.1% at the N gene level. It was also observed that the N gene of eight TCV isolates originating from various regions of the USA could not be amplified by the primers designed from the N gene of bovine coronavirus (BCV).

[Imaging of breast tumors using MR elastography]

PURPOSE

Imaging of breast tumors using MR-Elastography.

MATERIAL AND METHOD

Low-frequency mechanical waves are transmitted into breast-tissue by means of an oscillator. The local characteristics of the mechanical wave are determined by the elastic properties of the tissue. By means of a motion-sensitive spin-echo-sequence these waves can be displayed within the phase of the MR image. Subsequently, these images can be used to reconstruct the local distribution of elasticity. In-vivo measurements were performed in 3 female patients with malignant tumors of the breast.

RESULTS

All patients tolerated the measurement set-up without any untoward sensation in the contact area of skin and oszillator. The waves completely penetrated the breast, encompassing the axilla and regions close to the chest wall. All tumors were localized by MRE as structures of markedly stiffer tissue when compared to the surrounding tissue. Furthermore, in one patient, a metastasis in an axillary lymph node was detected. In all patients, local regions of increased elasticity were found in the remaining parenchyma of the breast, which, however, did not reach the high levels of elasticity found in the tumors.

CONCLUSION

MRE is an imaging modality enabling adjunct tissue differentiation of mammary tumors.

Single atoms in an optical dipole trap: towards a deterministic source of cold atoms

We describe a simple experimental technique which allows us to store a small and deterministic number of neutral atoms in an optical dipole trap. The desired atom number is prepared in a magneto-optical trap overlapped with a single focused Nd:YAG laser beam. Dipole trap loading efficiency of 100% and storage times of about one minute have been achieved. We have also prepared atoms in a certain hyperfine state and demonstrated the feasibility of a state-selective detection via resonance fluorescence at the level of a few neutral atoms. A spin relaxation time of the polarized sample of 4.2+/-0.7 s has been measured. Possible applications are briefly discussed.

Detection of antibody to turkey coronavirus by antibody-capture enzyme-linked immunosorbent assay utilizing infectious bronchitis virus antigen

An antibody-capture enzyme-linked immunosorbent assay (ELISA) for detection of antibody to turkey coronavirus (TCV) utilizing infectious bronchitis virus (IBV) antigen was developed. Anti-TCV hyperimmune turkey serum and normal turkey serum were used as positive or negative control serum for optimization of the ELISA system. Goat anti-turkey immunoglobulin G (light plus heavy chains) conjugated with horseradish peroxidase was used as detector antibody. The performance of the ELISA system was evaluated with 45 normal turkey sera and 325 turkey sera from the field and the cutoff point was determined. Serum samples of turkeys experimentally infected with TCV collected sequentially from 1 to 63 days postinfection were applied to the established antibody-capture ELISA using IBV antigens. The optimum conditions for differentiation between anti-TCV hyperimmune serum and normal turkey serum were serum dilution at 1:40 and conjugate dilution at 1:1600. Of the 325 sera from the field, 175 were positive for TCV by immunofluorescent antibody (IFA) assay. The sensitivity and specificity of the ELISA relative to IFA test were 93.1% and 96.7%, respectively, based on the results of serum samples from the field turkey flocks using the optimum cutoff point of 0.18 as determined by the logistic regression method. The ELISA values of all 45 normal turkey sera were completely separated from that of IFA-positive sera. The ELISA results of serum samples collected from turkeys experimentally infected with TCV were comparable to that of the IFA assay. Reactivity of anti-rotavirus, anti-reovirus, anti-adenovirus, or anti-enterovirus antibodies with the IBV antigens coated in the commercially available ELISA plates coated with IBV antigens could be utilized for detection of antibodies to TCV in antibody-capture ELISA.

High-resolution tensor MR elastography for breast tumour detection

MR elastography is a novel imaging technique for the visualization of elastic properties of tissue. It is expected that this method will have diagnostic value for the clarification of suspicious breast lesions. Low-frequency mechanical waves are coupled into the tissue and visualized via an MR sequence which is phase-locked to the mechanical excitation. Commonly, elasticity is assumed to be isotropic and reconstruction is performed in only two dimensions. The technique is extended to three dimensions such that the entire symmetric elasticity tensor is assessed. This is achieved by measuring different phases of the mechanical wave during one oscillatory cycle. Thereby it is possible to provide information about the anisotropy of the elasticity tensor. Finite-element simulations as well as phantom experiments are performed to demonstrate the feasibility of the method. Initial clinical results of a breast carcinoma are presented. The analysis of the eigenvalues of the elasticity tensor support the hypothesis that breast carcinoma might exhibit an anisotropic elasticity distribution. The surrounding benign tissue appears isotropic. Thereby new and additional diagnostic information is provided which might help in distinguishing between benign and malignant breast diseases.

[Measurement of the distance of the rectal mucosa from a gynecologic afterloading applicator based on the drop in performance of a cobalt-60-source]

PURPOSE

Assessment of the distance from a gynecological afterloading applicator to the rectum mucosa.

METHODS

The appropriate afterloading applicator for HDR-Ir-therapy is used for that purpose. A Co-60-source (370 MBq) with a guiding wire is positioned at the tip of the applicator and then withdrawn in steps of 1 cm. For each of these points the maximum dose at the rectum mucosa is measured with an ionisation chamber. From a reference curve it is then possible to determine the distance from the rectum mucosa to the applicator and to mark it in the calculated isodose plan. The actual daily dose to the rectum mucosa is planned not to exceed 3.0 Gy in the maximum.

RESULTS

Up to now the measurements were performed in 91 patients. The minimal distances of the rectum mucosa from the applicator were found to range from 5 to 18 mm with an average value of 14 mm.

CONCLUSIONS

The comparison of the measurement with the readings of the rectum probe during each session showed, that the method is suitable to avoid an overdose at the rectum mucosa.

[Comparison of the dorsal position with the semi-lateral position for irradiation of the breast]

In breast-conserving therapy of the mamma, patients are irradiated in a dorsal or hemi-lateral position. Both positioning techniques were investigated in twelve patients and then compared in order to assess the effect of the position on the dose distribution. It was shown that, in dependence on the individual conditions, both irradiation techniques can be used to optimize the dose distribution.

Immunization against psittacine pox

Pox virus isolated from psittacine birds was used as a vaccine in trials with love birds (Agapornis roseicollis). The vaccine was applied by wing-web puncture using single- and double-needle applicators. Immunity was effective against challenge with virulent psittacine pox virus administered via the feather follicle/thigh. When unvaccinated contact control birds were placed with the vaccinated individuals immediately post-vaccination, virus spread was evident. However, susceptible birds placed with vaccinated ones at 27 days postvaccination remained uninfected for 11 weeks. The importance of a high vaccine virus titer was observed.

[Irradiation planning in conservative treatment of cancer of the breast (author's transl)]

Investigations of homogeneous irradiation of the breast with opposed wedge filter fields are presented. Isodose plans calculated with the help of computer programs were compared with measurements of isodose distributions (LiF rods in polystyrol phantoms), and the possibility of optimizing the irradiation method by means of computed plans was examined. Differences between the calculated and the measured values maximally amounted to 10% (programs SIDOS U2 and COMRAD). The calculations correctly describe the place of dose maxima, the homogeneity of the irradiation and tendency to isodose shift caused by variation of the shape of the breast, of the angle of incidence of radiation and of the angles of the wedges. The results are demonstrated using isodose lines in the mediolateral and in the craniocaudal plane of the breast.

Diffusion hyperoxia following preoxygenation

Several minutes of 100 percent O2 breathing prior to inhalation induction with 79 percent N23 results in consistently higher PaO2 values during the first 10 minutes compared with prior air breathing. The theoretic maximum concentrating action of N2O uptake upon O2 is approximately the same (60 torr) regardless of gas breathed before induction.

Selective removal of hypersecreting pituitary adenomas? An analysis of endocrine function, operative and microscopical findings in 101 cases

The aim of this study of 101 pre- and postoperatively controlled hypersecreting pituitary adenomas (80 acromegalies, 15 Cushing's diseases, 6 Nelson's syndromes) was to establish in what cases a selective adenoma extirpation by the transnasal route is possible and advisable. In primary operations on acromegalics with small and medium size tumours 92% were postoperatively GH normal. Eighty five per cent of these had intact pituitary function. The results with larger tumours were worse (72%). During a control period of 1.5-5.5 years a renewed elevation of GH levels was observed in three cases, all in the first year, but never after clearly selective adenomectomy. These results, and the anterior lobe biopsies, which showed no GH cell hyperplasia, favour selective adenoma extirpation. In contrast to acromegaly, nodular ACTH cell hyperplasia in the anterior lobe was found in most cases of Cushing's disease, and therefore complete hypophysectomy was performed. The cortisol levels became either normal or, in most cases, lower than normal. A selective operation was performed on 6 Nelson tumors. The ACTH values became normal in about 50% of the patients but there was a tendency towards recurrence. Our experiences with Cushing's disease and Nelson's syndrome lead us to recommend total hypophysectomy.

[Plasma ACTH and Nelson tumors in bilaterally adrenalectomized Cushing patients]

Bilaterally adrenalectomized patients (18) because of Cushing's syndrome were studied. 16 of these 18 persons exhibited fairly high plasma ACTH levels. Distinctly elevated plasma ACTH levels were observed in 6 of them. 5 patients of this group showed an enlarged sella and deep pigmentation of the skin. 4 of the latter group had a mucoid cell adenoma which was removed selectively. After the surgery the ACTH values were found to be within normal range without any significant endocrine dysfunction of the pituitary. A long-term ACTH survey revealed that the ACTH levels remained within the ranges of bilaterally adrenalectomized Cushing patients without concomitant enlargement of the sella or pigmentation.