Prognostic factors for local recurrence and survival and impact of local treatments on survival in lacrimal gland carcinoma

BACKGROUND/AIMS

To identify prognostic factors for local recurrence, distant metastasis and disease-specific survival (DSS) for lacrimal gland carcinoma.

METHODS

All consecutive patients with lacrimal gland carcinoma treated from January 1998 through December 2018 were included. Log-rank tests and univariate Cox proportional hazards regression models were used to study risk factors and survival.

RESULTS

Overall, 55 patients were included in this study, and 5 patients were excluded from the survival analysis. Median age was 46 years (range: 10-76). 43 patients (78%) had adenoid cystic carcinoma (ACC). 31 patients (56%) had T2 disease at presentation. 28 patients (51%) underwent orbital exenteration with or without adjuvant radiotherapy or chemoradiation, 26 (47%) underwent eye-sparing surgery with or without adjuvant radiotherapy or chemoradiation, and 1 received palliative chemoradiation. 11 patients (22%) experienced local recurrence; 14 (29%) experienced distant metastasis. Five- and 10-year local-recurrence-free survival rates were 0.71 (95% CI 0.58 to 0.88), and 5- and 10-year distant-metastasis-free survival rates were 0.67 (95% CI 0.53 to 0.85) and 0.49 (95% CI 0.30 to 0.81), respectively. There was no significant difference in risks of local recurrence, distant metastasis or DSS between ACC patients who had orbital exenteration and those who had eye-sparing surgery. Perineural invasion was negatively associated with local-recurrence-free survival (p=0.02). Among patients with ACC, basaloid/solid histologic type was associated with significantly worse DSS than non-basaloid/solid histologic type (p<0.01).

CONCLUSIONS

For lacrimal gland carcinoma, orbital exenteration with adjuvant therapy and eye-sparing surgery with adjuvant therapy are associated with similar recurrence outcomes. Eye-sparing surgery is associated with better DSS. Perineural invasion is a risk factor for local recurrence. ACC with basaloid/solid subtype correlates with worse DSS.

Prognostic Factors for Orbital Exenteration, Local Recurrence, Metastasis, and Death From Disease in Conjunctival Squamous Cell Carcinoma

PURPOSE

Information regarding risk of metastasis and disease-related death (DD) from conjunctival squamous cell carcinoma (SCC) is relatively scarce. We explored prognostic factors for orbital exenteration, local recurrence, nodal metastasis, and DD in patients with conjunctival SCC.

DESIGN

Retrospective cross-sectional study.

METHODS

All consecutive patients with conjunctival SCC treated by the senior author at MD Anderson Cancer Center during1999-2018 were included. Survival curves were estimated using the Kaplan-Meier method, and survival differences were assessed using 2-sided log-rank tests.

RESULTS

The study included 44 patients (24 men, 20 women); median age was 64 years (range, 40-90). T categories at presentation were as follows: Tis, 20 patients; T2, 8; T3, 9; and T4, 7. Eighteen patients (41%) had tumors exclusively in the bulbar conjunctiva; 26(59%) had nonbulbar conjunctival involvement. The median follow-up time was 29.2 months (95% CI: 21.8-44.3). Orbital exenteration was performed in 10 cases (23%) and was associated with T3 or more advanced disease at presentation (p < 0.001). Seven patients developed local recurrence during follow up. History of organ transplant correlated with local recurrence and orbital exenteration (p < 0.01). Nodal metastasis was present in 1 patient at presentation and occurred in 3 patients during follow up, for an overall nodal metastasis rate of 9% (4/44). By end of follow up, 2 patients had died of disease, 4 had died of other causes, and 38 were alive with no evidence of disease. The results suggest that both orbital exenteration and nodal metastasis are independent variables associated with DD.

CONCLUSIONS

In patients with conjunctival SCC, orbital exenteration and nodal metastasis are associated with DD and organ transplantation is associated with orbital exenteration.

High-speed evaluation of track-structure Monte Carlo electron transport simulations

There are many instances where Monte Carlo simulation using the track-structure method for electron transport is necessary for the accurate analytical computation and estimation of dose and other tally data. Because of the large electron interaction cross-sections and highly anisotropic scattering behavior, the track-structure method requires an enormous amount of computation time. For microdosimetry, radiation biology and other applications involving small site and tally sizes, low electron energies or high-Z/low-Z material interfaces where the track-structure method is preferred, a computational device called a field-programmable gate array (FPGA) is capable of executing track-structure Monte Carlo electron-transport simulations as fast as or faster than a standard computer can complete an identical simulation using the condensed history (CH) technique. In this paper, data from FPGA-based track-structure electron-transport computations are presented for five test cases, from simple slab-style geometries to radiation biology applications involving electrons incident on endosteal bone surface cells. For the most complex test case presented, an FPGA is capable of evaluating track-structure electron-transport problems more than 500 times faster than a standard computer can perform the same track-structure simulation and with comparable accuracy.

Dietary fish oil and pectin enhance colonocyte apoptosis in part through suppression of PPARdelta/PGE2 and elevation of PGE3

We have shown that dietary fish oil and pectin (FP) protects against radiation-enhanced colon cancer by upregulating apoptosis in colonic mucosa. To investigate the mechanism of action, we provided rats (n = 40) with diets containing the combination of FP or corn oil and cellulose (CC) prior to exposure to 1 Gy, 1 GeV/nucleon Fe-ion. All rats were injected with a colon-specific carcinogen, azoxymethane (AOM; 15 mg/kg), 10 and 17 days after irradiation. Levels of colonocyte apoptosis, prostaglandin E(2) (PGE(2)), PGE(3), microsomal prostaglandin E synthase-2 (mPGES-2), total beta-catenin, nuclear beta-catenin staining (%) and peroxisome proliferator-activated receptor delta (PPARdelta) expression were quantified 31 weeks after the last AOM injection. FP induced a higher (P < 0.01) apoptotic index in both treatment groups, which was associated with suppression (P < 0.05) of antiapoptotic mediators in the cyclooxygenase (COX) pathway (mPGES-2 and PGE(2)) and the Wnt/beta-catenin pathway [total beta-catenin and nuclear beta-catenin staining (%); P < 0.01] compared with the CC diet. Downregulation of COX and Wnt/beta-catenin pathways was associated with a concurrent suppression (P < 0.05) of PPARdelta levels in FP-fed rats. In addition, colonic mucosa from FP animals contained (P < 0.05) a proapoptotic, eicosapentaenoic acid-derived COX metabolite, PGE(3). These results indicate that FP enhances colonocyte apoptosis in AOM-alone and irradiated AOM rats, in part through the suppression of PPARdelta and PGE(2) and elevation of PGE(3). These data suggest that the dietary FP combination may be used as a possible countermeasure to colon carcinogenesis, as apoptosis is enhanced even when colonocytes are exposed to radiation and/or an alkylating agent.

Radiation responses of perfused tracheal tissue

We are using a novel perfusion system to examine the effects of radiation on a model respiratory tissue. Tracheas taken from young adult male Fischer 344 rats are embedded in a growth factor-enriched agarose matrix that is mounted in a special apparatus designed to allow growth medium to periodically wash the epithelial surface of the lumen. A comparison of the microarray expression profiles of freshly harvested tracheas and tracheas maintained in perfusion culture for 24 h shows no significant difference except for an increase in expression of a few metabolism- and surfactant-related genes. Perfusion culture samples exposed to 4 Gy of X rays show a lower than expected increase in expression for some cell cycle- and repair-related genes.

Bound PCNA in nuclei of primary rat tracheal epithelial cells after exposure to very low doses of plutonium-238 alpha particles

Bystander effects from ionizing radiation have been detailed for a number of cell systems and a number of end points. We wished to use a cell culture/ex vivo rat model of respiratory tissue to determine whether a bystander effect detected in culture could also be shown in a tissue. Examination by immunofluorescence techniques of tracheal cell cultures after exposure to very low doses of alpha particles revealed a large proportion of cells with proliferating cell nuclear antigen (PCNA) bound in their nuclei. PCNA was selected as an end point because it is involved in both DNA repair and the changes in cell cycle that are typical of many reported bystander effects. Maximum response can be detected in up to 28% of the cells in sub-confluent cultures with a dose of only 2 mGy. At this dose less than 2% of the cell nuclei have experienced a particle traversal and less than 6% of the cells have experienced an alpha-particle traversal through either their nucleus or some part of their cytoplasm. The hypothesis that this bystander response in nontargeted cells is mediated through secreted factor(s) is presented, and supporting evidence was found using partial irradiation and co-culture experiments. Examination of the effect with excised pieces of trachea demonstrated a response similar to that seen in culture.

Influence of cell position relative to planar alpha-particle sources on survival and preneoplastic transformation of primary rat tracheal epithelial cells

Rat tracheal epithelial cells exposed directly on planar 210Po sources exhibited exponential cell killing; however, no significant increase in induction of preneoplastic transformation was observed over a range of alpha-particle fluences (0.017-0.050 micron-2). In contrast, up to 10-fold increases in frequencies of preneoplastic transformants, above control levels, were observed after exposure of rat tracheal epithelial cells to similar alpha-particle fluences on 238Pu and 241Am sources. Two alternative hypotheses are evaluated as an explanation for this apparent difference in the biological effect of alpha particles emitted from different sources: (a) possible interactions between effects produced by alpha particles and by low-energy photons, which occur with 238Pu and 241Am but not with 210Po; and (b) the influence of spatial relationships between exposed cells and the surface of the planar source. The data suggest that cell-to-source spatial relationships affect both survival and transformation markedly.

Effects of 210Po alpha particles on survival and preneoplastic transformation of primary rat tracheal epithelial cells irradiated while in suspension or in the intact tissue

Rat tracheal epithelial cells exhibited exponential cell killing when exposed to 210Po alpha particles as single cell suspensions or in the intact tissue. Survival of cells in the intact tissue was not significantly different from that observed with cell suspensions. Comparison of survival of cells exposed in suspension to 300 kVpX rays yielded an RBE of 6.3. Measurements of basal cell nuclei were used to determine that a single traversal of a cell nucleus had a high probability of causing cell inactivation. This was also observed in mink lung cells and CHO cells exposed in an identical manner. There were no significant increases in frequencies of preneoplastic transformation observed for a range of exposures (0.0007 to 0.05 alpha particles/micron2). Examination of intact tracheal transplants which were irradiated with alpha particles also failed to reveal any preneoplastic or neoplastic changes.

Characteristics of magnetically separated rat tracheal epithelial cell populations

A simple magnetic separation technique has been developed using lectins specific for two of the cell types found in the tracheal mucosa. The resulting populations of basal and secretory cells were examined for proliferative capacity in culture and in vivo. The basal cell fraction contains the cells that proliferate in culture and respond to 12-O-tetradecanoylphorbol-13-acetate. In addition, the basal cell fraction exhibited the highest proliferative capacity in vivo during the first few days after transplantation. Repopulation of inverted intestinal segments showed that only with suspensions containing a significant proportion of basal cells could a mucociliary lining be established. Segments receiving the same number of unsorted or predominantly mucous secreting cells did not repopulate in vivo. These data support the hypothesis that the basal cell is most likely the stem cell of the tracheal epithelium.

Basal cells are the progenitors of primary tracheal epithelial cell cultures

The goal of this study was to identify the cells from the rat tracheal epithelium which attach and proliferate in primary culture. When cells isolated from tracheas by enzymatic digestion were held in suspension at 37 degrees C for several hours most of the differentiated cells died. The kinetics of this selective cell death were not dependent on the constituents of the holding medium. With time in suspension, the colony forming efficiency of the surviving cells increased two- to threefold. Comparison of the growth curves of cells held or plated directly showed no difference in the number of cells in the proliferating populations. Using two lectins, it was possible to monitor the loss of specific populations in suspension. BS1-B4 is a marker for basal cells and UEA-1 is a secretory cell marker. Only those cells that were BS1-B4 positive survived in suspension. Further, the colonies that formed in primary culture were positive for this marker. Single cell suspensions of cells were sorted by flow cytometry and a fivefold increase in the colony forming efficiency of BS1-B4 positive cells compared to that of the negative cells was observed. These findings suggest that the cells that survived in suspension and proliferated in culture originated from the basal cells of the trachea.

Secretion of LH, FSH and oestradiol-17 beta during the follicular phase of the oestrous cycle in the ewe

Plasma concentrations of LH, FSH and oestradiol-17 beta were measured in blood samples taken at 15 min intervals for 48 h during the follicular phase of four Merino ewes. The amplitude of pulses of LH and the mean concentration of LH were higher at the beginning of the follicular phase, 36-24 h before the preovulatory surge of LH (amplitude 2.4 ng ml-1, mean concentration 3.9 ng ml-1), than at the end, 24-0 h before the preovulatory surge (amplitude 1.2 +/- 0.1 ng ml-1; mean concentration 1.4 +/- 0.1 ng ml-1). There was no change in the inter-pulse interval during this time (mean 74 +/- 5 min). Over the same period, oestradiol levels increased from 7-8 pg ml-1 to a peak of 10-15 pg ml-1. Mean FSH concentrations declined (36-24 h: 3.6 ng ml-1 vs 24-0 h: 1.8 +/- 0.3 ng ml-1) before rising at the time of the preovulatory surge of LH and again 24 h later. It was concluded that the biphasic response of LH to oestrogen that is seen in ovariectomized ewes may also operate during the follicular phase of the oestrous cycle in entire ewes.

An in vitro model of acetaldehyde metabolism by rodent conceptuses

A culture model is described for the study of acetaldehyde (AcH) metabolism by explanted postimplantation rat and mouse conceptuses. The ability of 12-d rat and 10-d mouse embryos to metabolise AcH was demonstrated. The elimination rate for the 12-d rat conceptus using an initial AcH concentration of 1 mM in the medium was found to be 1.8 nmol/mg per minute. When the conceptus was divided into embryonic and extraembryonic tissue, the rates were 1.6 and 2.2 nmol/mg per minute, respectively. When the AcH concentration was reduced to 50 microM the rate was 0.095 nmol/mg per minute. The results provide further evidence for a functional barrier that prevents AcH entry to the embryo. A comparative experiment using CBA/beige mouse conceptuses showed that AcH elimination characteristics may be qualitatively similar to those in rat embryos, but that the estimated elimination rate of 0.8 nmol/mg per minute was less than half that of the rat. Thus the "metabolic barrier" may be less efficient in the mouse. This may be important in view of the greater sensitivity of the mouse to ethanol embryotoxicity.