Francis E. Sharkey

Considerations in the use of nude mice for cancer research

SummaryTransplants of human tumors in nude mice have shown a progressive increase during the past 15 years as an experimental model for cancer research. A variety of factors, including relatively fragile health, have been identified that require appropriate experimental controls if the investigator is to obtain consistent results.Not all tumors grow in nude mice. The frequency of tumor ‘take’ varies according to tumor origin, tumor type, inoculation site, age and conditioning of the mouse host, and a variety of other factors. Manipulation of these variables has led to successful propagation of almost every known variety of human malignancy. Following transplant, changes in characteristics have been documented, but the frequency and degree of such changes remains uncertain. Tumor growth rate probably increases after transplantation, requiring great care in the interpretation of chemotherapy experiments, but biochemical characteristics may be more stable. The nude mouse offers great interest as a model for the in vivo study of metastasis, as a number of experimental variables, mainly immunological, have been shown to affect this process. Spontaneous tumors have been shown to arise in these animals, but the controversy over their frequency relative to the thymus-brearing background strain is unresolved.We conclude that the nude mouse/tumor xenograft model, while requiring meticulous experimental controls, is nevertheless an extremely useful tool for cancer research.

Radiofrequency tissue ablation: Effect of hepatic blood flow occlusion on thermal injuries produced in cirrhotic livers

AbstractBackground: Radiofrequency thermal ablation has been used as a treatment for several types of hepatic malignancies. Many of these lesions exist in the presence of cirrhosis. Limitations exist to the size of the ablations and, subsequently, the efficacy of treatment. Hepatic vascular inflow occlusion has been advocated as an adjunctive measure to increase the efficacy of the ablation. We present a model in the human cirrhotic liver that demonstrates the advantage of blood flow occlusion during radiofrequency ablation. Methods: Five patients with advanced endstage liver disease scheduled to have orthotopic liver transplantation were enrolled in this study. After laparotomy and before hepatectomy, radiofrequency ablation was performed without and with hepatic blood flow occlusion. After hepatectomy, the liver was sectioned, the area of ablation was measured in three dimensions, and the volume of ablation calculated. Results: Three of the patients had had previously placed transjugular intrahepatic portosystemic shunt. The mean volume of the ablation without blood flow occlusion was 22.5 ± 7.4 cm3 and that with blood flow occlusion was 48.4 ± 24.0 cm3 (P = .05). Conclusions: Ablation area is increased significantly with hepatic blood flow occlusion in the human cirrhotic liver. This result may have application in the treatment of larger (>3 cm) hepatic malignancies.

Urogenital tract carcinoma metastatic to the head and neck

A 9‐year review of our experience with head and neck metastases from 845 urogenital tract tumors of the kidney, prostate, bladder, testicle, spermatic cord, penis, urethra, and ureter was performed. Thirty‐one (3.7%) of these tumors developed metastases to the cervical and supraclavicular lymph nodes, scalp, thyroid gland, thyroid cartilage, parotid gland, retroorbit, mandible, nasal cavity, and paranasal sinuses. Unusual cases and a review of the literature are presented. The frequency of such metastases to the head and neck from various primaries, diagnostic application of current immunohistochemical methodology, and therapeutic alternatives are emphasized.

Colorectal cancer in Hispanics: a population at risk for earlier onset, advanced disease, and decreased survival.

Background:While colorectal cancer (CRC) incidence and mortality rates have declined slightly over the past decade, there remain marked differences by ethnicity. Our aim was to investigate ethnic differences in occurrence, clinical presentation and outcome of CRC at a tertiary university center that serves a predominantly Hispanic population. Methods:Prospectively collected data from the tumor registry on patients diagnosed with colorectal cancer from 1985 through 2001 was examined. Age at diagnosis, mode of presentation, sex, tumor location, ethnicity, TNM stage, and survivals were assessed and ethnic differences were sought. Results:Records from 453 patients with CRC were reviewed. There were 296 (65%) patients that were Hispanics, 112 (25%) non-Hispanic Whites, 37 (8%) African Americans, and 8 (2%) of other or unknown ethnicity. Compared with non-Hispanic Whites, Hispanics presented at a younger age (58.5 ± 14 versus 53.6 ± 12.73, respectively; P < 0.01), with a significantly greater incidence of stage IV disease (19% versus 32%, respectively; P = 0.02). They had significantly poorer age-adjusted survival (median survival of 92 months for <55 years and 77 months for >55 years versus 48 months for <55 years and 48 months for >55 years, respectively; adjusted log rank P = 0.045). There were no differences in tumor location, mode of presentation or adjuvant treatment received. Conclusions:Hispanic patients with CRC in our catchment area present at a younger age with more metastatic disease and have a poorer survival than non-Hispanic Whites. Modification of screening criteria and treatment paradigms may be required for Hispanics.

Oral bropirimine immunotherapy of bladder carcinoma in situ after prior intravesical bacille Calmette-Guérin

OBJECTIVES Bropirimine is an oral immunomodulator that has demonstrated anticancer activity in transitional cell carcinoma in situ (CIS) in both the bladder and upper urinary tract. Activity also has been documented in patients after prior therapy with bacille Calmette-Guérin (BCG). To more accurately estimate bropirimines efficacy in BCG-resistant bladder CIS, a Phase II trial was performed. A separate analysis was performed in additional patients intolerant of BCG toxicity. METHODS Patients received bropirimine 3.0 g/day by mouth for 3 consecutive days, weekly, for up to 1 year. Bladder biopsies and cytologic examination were performed quarterly. Complete response (CR) required negative biopsy and cytology results. RESULTS Twenty-one of 86 patients entered were not evaluable. CR was seen in 21 (32%; 95th percentile confidence interval [CI], 21% to 44%) of 65 evaluable patients, including 14 (30%, CI 17% to 43%) of 47 BCG-resistant, and 7 (39%, CI 16% to 61%) of 18 BCG-intolerant patients. Overall, by intent-to-treat analysis, CR was thus seen in 21 (24%) of 86 subjects. Most BCG-resistant patients were failures to BCG without relapse, and had received 12 to 36 (median 12) BCG treatments; intolerant patients had received 4 to 11 treatments (median 6). Response duration ranged from 65 to 810 days, with median not yet reached (but greater than 12 months). Thirteen (15%) of 86 stopped bropirimine due to toxicity. Progression to invasive or metastatic disease during or immediately after therapy was documented in only 4 patients (6%), all nonresponders. CONCLUSIONS Bropirimine may be an alternative to cystectomy for some patients with bladder CIS who have failed or have not tolerated BCG. Further evaluation to improve responses and durability is warranted.

Observer reproducibility during computer-assisted planimetric measurements of nuclear features.

To evaluate observer variance during microprocessor-assisted planimetry, nuclear features (area, perimeter, and form factor) were studied in a series of mammary ductal carcinomas. Fragments of formalin-fixed, paraffin-embedded tissue were re-embedded in plastic, sectioned at 1 micron, stained with methylene blue, and studied with a Zeiss-Kontron MOP-3 microprocessor-assisted planimeter. Both interobserver and intraobserver reproducibility were evaluated, the former among three different observers and the latter by two observers repeating their own measurements. Reproducibility was good for measurement of area, but deteriorated progressively for measurement of perimeter and form factor. Not only was observer correlation poor (identified via linear regression), but paired t-tests also showed consistent variation among observers. The major difficulty was in following the irregular nuclear contours that are characteristic of cancer cells. It is concluded that adequate demonstration of observer reproducibility remains an essential part of tissue investigation, even when the objective methods typical of morphometry are used.

Acute hepatic allograft rejection: a comparison of patients with and without centrilobular alterations during first rejection episode.

The histologic diagnosis of acute hepatic allograft rejection is usually based upon the identification of characteristic portal tract features. In addition to these, centrilobular alterations such as central vein endothelialitis, zone 3 inflammation, and hepatocyte necrosis may also be seen during episodes of acute rejection. The purpose of this study was to identify any differences in the subsequent clinical course of patients with and without centrilobular alterations during their first biopsy‐proven episode of acute rejection. Acute rejection was diagnosed at least once in 35 liver recipients who had undergone allograft biopsy. Of these, 15 (43%) had centrilobular alterations in their first posttransplant biopsy. These 15 patients developed ductopenia (60% vs. 30%) and subsequent episodes of acute rejection (53% vs. 25%) more often than did the 20 patients who lacked centrilobular alterations in their first posttransplant biopsy. Time to first episode of acute rejection and rates of subsequent recurrent hepatitis and death were similar between the 2 groups. Patients with centrilobular alterations during a first episode of acute rejection are more likely to have subsequent episodes of acute rejection and to develop features of chronic rejection than are patients without these changes. These patients may benefit from more vigilant clinical follow‐up and/or higher levels of immunosuppression. (Liver Transpl 2004;10:369–373.)

The Significance of Central Pathology Review in Clinical Studies of Transitional Cell Carcinoma in Situ

PURPOSE The causes of interobserver variation in the pathological diagnosis of urothelial neoplasia were studied. MATERIALS AND METHODS A central review was performed on pathological specimens in a multi-institutional clinical study of patients with in situ transitional cell carcinoma of the bladder. RESULTS A significant discrepancy in pathological diagnosis was noted between the original report and the central review in 60 of 159 biopsies (38%) and in 73 of 217 cytology specimens (34%). Biopsy discrepancies were almost equally divided between upgrades and downgrades, whereas 89% of cytology discrepancies involved an upgrade in diagnosis by the central reviewer. The most significant factor causing variability in biopsy diagnoses was the multiplicity of classifications used by the originating pathologists. Other factors included fixation and biopsy artifacts. Cell degeneration secondary to treatment was the most important factor resulting in cytology under grading. At originating institutions the correlation of diagnoses between concurrent biopsy and cytology specimens was poor. CONCLUSIONS The lack of a well accepted standard for the histopathological diagnosis of transitional cell carcinoma in situ poses a major problem for multi-institutional studies of this disease. Organizers must include a histopathological standard in the study plan and publicize it to all participants, particularly pathologists. Central review of pathological specimens is essential to maintain data integrity.

The prognostic significance of vascular channel involvement and deep stromal penetration in early cervical carcinoma.

EIGIITY-EIGHT PATIENTS WITH FIGO Stage Ib and IIa squamous cell carcinoma of the cervix underwent radical hysterectomy with pelvic and paraaortic lymphadenectomy. The records and histopathologic material were reviewed to determine the prognostic significance of vascular channel involvement and deep stromal penetration by tumor. Seventy-four patients (84%) were alive and free of disease for more than 2 years and 14 (16%) developed recurrent carcinoma within that time. A positive correlation was found between depth of stromal penetration by tumor and the degree of vascular channel involvement (p <0.05). Vascular involvement in itself did not significantly affect nodal status, survival or the rate of recurrence. Depth of penetration was associated with a higher incidence of positive nodes (p <0.05). There was a trend towards a lower survival rate and a higher recurrence rate in patients with deep stromal penetration as compared to those with superficial tumors. Microscopic nodal disease increased the rate of recurrence and had an adverse effect on survival. The combination of deep tumor penetration and positive nodes in the same patient was associated with the highest recurrence rate and the lowest survival (p <0.05). Nodal status was a more significant prognostic indicator than depth of tumor penetration because patients with deeply penetrating tumors and positive nodes had more than twice the recurrence rate than did patients with deep tumors and negative nodes. Postoperative radiation therapy was beneficial to patients whose tumors demonstrated deep stromal penetration and microscopic metastases to pelvic lymph nodes.

Tumor-associated antigens in breast carcinomas. Prognostic significance

In an attempt to identify biologic markers that might predict prognosis in breast cancer patients, the presence or absence of seven tumor‐associated antigens in 54 infiltrating breast carcinomas was correlated with tumor recurrence rates (minimum five‐year follow‐up), axillary lymph node metastases and tumor volume. Immunohistochemical kappa‐casein was present in 30 (56%) tumors, alpha‐lactalbumin in 39 (72%) tumors, secretory component of IgA in 26 (48%) tumors, carcinoembryonic antigen in 34 (63%) tumors, pregnancy‐specific beta‐1‐glycoprotein in 7 (13%) tumors, beta subunit of human chorionic gonadotrophin in 1 (2%) tumor and human placental lactogen in 0 (0%) tumors. There was no significant correlation between the presence or absence in tumor of any of the antigens, and prognosis as assessed either by 5‐year recurrence rates (P > 0.18) or by the presence of axillary lymph node metastases (P > 0.20). No significant difference was noted in mean tumor volume (cm3) ±SEM, between tumors with or without antigen immunoreactivity (P > 0.05).