68 Ga-Pentixafor PET/CT for In Vivo Imaging of CXCR4 Receptors in Glioma Demonstrating a Potential for Response Assessment to Radiochemotherapy: Preliminary Results

PURPOSE

The aim of this study was to evaluate the diagnostic potential of 68 Ga-pentixafor PET/CT for in vivo CXCR4 receptors imaging in glioma and its possible role in response assessment to radiochemotherapy (R-CT).

METHODS

Nineteen (12 men, 7 women) patients with glioblastoma multiforme (GBM) underwent 68 Ga-pentixafor PET/CT, contrast-enhanced MR, and MR spectroscopy. Patients were divided in to 2 groups, that is, group I was the presurgical (n = 9) group in which the scanning was done before surgery, and PET findings were correlated with CXCR4 receptors' density. The group II was the postsurgical (n = 10) group in which the scanning was done before and after R-CT and used for treatment response evaluation. The quantitative analysis of 68 Ga-pentixafor PET/CT evaluated the mean SUV max , SUV mean , SUV peak , and T/B values. MR spectroscopy data evaluated the ratios of tumor metabolites (choline, NAA, creatine).

RESULTS

68 Ga-Pentixafor uptake was noted in all (n = 19) the patients. In the group I, the mean SUV max , SUV mean , SUV peak , and T/B values were found to be 4.5 ± 1.6, 0.60 ± 0.26, 1.95 ± 0.8, and 6.9 ± 4.6, respectively. A significant correlation ( P < 0.005) was found between SUV mean and choline/NAA ratio. Immunohistochemistry performed in 7/9 showed CXCR4 receptors' positivity (intensity 3 + ; stained cells >50.0%). In the group II, the mean SUV max at baseline was 4.6 ± 2.1 and did not differ (4.4 ± 1.6) significantly from the value noted at post-R-CT follow-up PET/CT imaging. At 6 months' clinical follow-up, 4 patients showed stable disease. SUV max and T/B ratios at follow-up imaging were lower (3.70 ± 0.90, 2.64 ± 1.35) than the corresponding values (4.40 ± 2.8; 2.91 ± 0.93) noted at baseline. Six (6/10) patients showed disease progression, and the mean SUV max , and T/B ratio in these patients were significantly ( P < 0.05) higher than the corresponding values at baseline and also higher than that noted in the stable patients.

CONCLUSIONS

68 Ga-Pentixafor PET/CT can be used for in vivo mapping of CXCR4 receptors in GBM. The technique after validation in a large cohort of patients may have added diagnostic value for the early detection of GBM recurrence and for treatment response evaluation.

68 Ga-Pentixafor PET/CT for in-vivo mapping of CXCR4 receptors as potential radiotheranostic targets in soft tissue and bone sarcoma: preliminary results

OBJECTIVE

To evaluate the diagnostic utility of 68 Ga-Pentixafor PET/CT for in vivo imaging of CXCR4 receptors in soft tissue/bone sarcoma.

METHODS

Ten (7M: 3F; mean age = 24.7 ± 14.2 years) consecutive patients with clinical and radiological evidence of bone/soft tissue sarcoma were recruited prospectively whole body 68 Ga-Pentixafor PET/CT imaging was performed at 60-min after tracer administration. After performing standard CT, PET acquisition from head to toe was done (3 min/bed position) in a caudocranial direction. PET/CT data was reconstructed and SUV max , SUV mean values, target-to-background ratio (TBR) and active tumor volume (cc) were computed for the tracer avid lesions. Histopathological and IHC analysis was performed on the surgically excised primary tumors. CXCR4 receptors' intensity was evaluated by visual scoring.

RESULTS

The mean SUV max and SUV mean values in the primary tumors were 4.80 ± 1.0 (3.9-7.7) and 2.40 ± 0.60 (0.9-4.0). The mean TBR and tumor volume (cc) were 1.84 ± 1.3 and 312.2 ± 285. Diagnosis of osteosarcoma in 7, chondrosarcoma, leiomyosarcoma and synovial sarcoma in 1 patient each was confirmed on HP analysis. Distant metastatic lesions were seen in 3/10 patients. Nuclear CXCR4 receptors' positivity was seen in 5, cytoplasmic in 4 and both pattern seen in 1 patient. The mean CXCR4 receptors' intensity was found to be 7.6 ± 2. The highest SUV max value of 7.7 was observed in the patient having both cytoplasmic and nuclear CXCR4 expression. SUV max was found to be poorly correlated ( r  = 0.441) with CXCR4 expression.

CONCLUSION

68 Ga-Pentixafor PET/CT detects CXCR4 receptors over-expressed in sarcoma, its radio-theranostics potential needs detailed evaluation.

Effectiveness of Azadirachta indica (neem) mouthrinse in plaque and gingivitis control: a systematic review

OBJECTIVES

The aim of this systematic review was to evaluate the effectiveness of Azadirachta indica (neem)-based herbal mouthrinse in improving plaque control and gingival health.

METHODS

Literature search was accomplished using electronic databases (PubMed, Cochrane Central Register of Controlled Trials and EMBASE) and manual searching, up to February 2015, for randomized controlled trials (RCTs) presenting clinical data for efficacy of neem mouthrinses when used alone or as an adjunct to mechanical oral hygiene as compared to chlorhexidine mouthrinses for controlling plaque and gingival inflammation in patients with gingivitis.

RESULTS

Of the total 206 articles searched, three randomized controlled trials evaluating neem-based herbal mouthrinses were included. Due to marked heterogeneity observed in study characteristics, meta-analysis was not performed. These studies reported that neem mouthrinse was as effective as chlorhexidine mouthrinse when used as an adjunct to toothbrushing in reducing plaque and gingival inflammation in gingivitis patients. However, the quality of reporting and evidence along with methods of studies was generally flawed with unclear risk of bias.

CONCLUSION

Despite the promising results shown in existing randomized controlled trials, the evidence concerning the clinical use of neem mouthrinses is lacking and needs further reinforcement with high-quality randomized controlled trials based on the reporting guidelines of herbal CONSORT statement.

Diffusion properties of conventional and calcium-sensitive MRI contrast agents in the rat cerebral cortex

Calcium-sensitive MRI contrast agents can only yield quantitative results if the agent concentration in the tissue is known. The agent concentration could be determined by diffusion modeling, if relevant parameters were available. We have established an MRI-based method capable of determining diffusion properties of conventional and calcium-sensitive agents. Simulations and experiments demonstrate that the method is applicable both for conventional contrast agents with a fixed relaxivity value and for calcium-sensitive contrast agents. The full pharmacokinetic time-course of gadolinium concentration estimates was observed by MRI before, during and after intracerebral administration of the agent, and the effective diffusion coefficient D* was determined by voxel-wise fitting of the solution to the diffusion equation. The method yielded whole brain coverage with a high spatial and temporal sampling. The use of two types of MRI sequences for sampling of the diffusion time courses was investigated: Look-Locker-based quantitative T(1) mapping, and T(1) -weighted MRI. The observation times of the proposed MRI method is long (up to 20 h) and consequently the diffusion distances covered are also long (2-4 mm). Despite this difference, the D* values in vivo were in agreement with previous findings using optical measurement techniques, based on observation times of a few minutes. The effective diffusion coefficient determined for the calcium-sensitive contrast agents may be used to determine local tissue concentrations and to design infusion protocols that maintain the agent concentration at a steady state, thereby enabling quantitative sensing of the local calcium concentration.

Aloe vera herbal dentifrices for plaque and gingivitis control: a systematic review

OBJECTIVES

To evaluate the effectiveness of aloe vera containing herbal dentifrices in improving plaque control and gingival health.

METHODS

A manual and electronic literature (MEDLINE and Cochrane Central Register of Controlled Trials) search was performed up to July 2012, for randomized controlled trials presenting clinical, microbiological, immunological, and patient-centered data for the efficacy of aloe vera herbal dentifrices for controlling plaque and gingival inflammation in patients with gingivitis.

RESULTS

From 79 titles and abstracts, eight full-text articles were screened and finally two randomized controlled trials were selected. These randomized controlled trials reported that aloe vera dentifrices were similar in efficacy to control dentifrices in effectively reducing plaque and gingival inflammation in gingivitis patients based on the assessment of clinical, microbiological, and patient-centered treatment outcomes. However, many important details (composition and characteristics of aloe vera and control dentifrices along with appropriate randomization, blinding, and outcomes assessed) were lacking in these trials, and therefore, the quality of reporting and methods was generally flawed with high risk of bias.

CONCLUSION

Even though there are some promising results, the clinical effectiveness of aloe vera herbal dentifrices is not sufficiently defined at present and warrants further investigations based on reporting guidelines of herbal CONSORT statement.

Improved neuronal tract tracing with stable biocytin-derived neuroimaging agents

One of the main characteristics of brains is their profuse connectivity at different spatial scales. Understanding brain function evidently first requires a comprehensive description of neuronal anatomical connections. Not surprisingly a large number of histological markers were developed over the years that can be used for tracing mono- or polysynaptic connections. Biocytin is a classical neuroanatomical tracer commonly used to map brain connectivity. However, the endogenous degradation of the molecule by the action of biotinidase enzymes precludes its applicability in long-term experiments and limits the quality and completeness of the rendered connections. With the aim to improve the stability of this classical tracer, two novel biocytin-derived compounds were designed and synthesized. Here we present their greatly improved stability in biological tissue along with retained capacity to function as neuronal tracers. The experiments, 24 and 96 h postinjection, demonstrated that the newly synthesized molecules yielded more detailed and complete information about brain networks than that obtained with conventional biocytin. Preliminary results suggest that the reported molecular designs can be further diversified for use as multimodal tracers in combined MRI and optical or electron microscopy experiments.

Synthesis and characterization of a smart contrast agent sensitive to calcium

A novel first-generation Ca2+ sensitive contrast agent, Gd-DOPTRA has been synthesized and characterized. The agent shows approximately 100% relaxivity enhancement upon addition of Ca2+. The agent is selective and sensitive to Ca2+ also in the presence of Mg2+ and Zn2+. The relaxivity studies carried out in physiological fluids prove the prospects of the agent for in vivo measurements.

Towards extracellular Ca2+ sensing by MRI: synthesis and calcium-dependent 1H and 17O relaxation studies of two novel bismacrocyclic Gd3+ complexes

Two new bismacrocyclic Gd³⁺ chelates containing a specific Ca²⁺ binding site were synthesized as potential MRI contrast agents for the detection of Ca²⁺ concentration changes at the millimolar level in the extracellular space. In the ligands, the Ca²⁺-sensitive BAPTA-bisamide central part is separated from the DO3A macrocycles either by an ethylene (L¹) or by a propylene (L²) unit [H₄BAPTA is 1,2-bis(o-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid; H₃DO₃A is 1,4,7,10-tetraazacyclododecane-1,4,7-triacetic acid]. The sensitivity of the Gd³⁺ complexes towards Ca²⁺ and Mg²⁺ was studied by ¹H relaxometric titrations. A maximum relaxivity increase of 15 and 10% was observed upon Ca²⁺ binding to Gd₂L¹ and Gd₂L², respectively, with a distinct selectivity of Gd₂L¹ towards Ca²⁺ compared with Mg²⁺. For Ca²⁺ binding, association constants of log K = 1.9 (Gd₂L¹) and log K = 2.7 (Gd₂L²) were determined by relaxometry. Luminescence lifetime measurements and UV–vis spectrophotometry on the corresponding Eu³⁺ analogues proved that the complexes exist in the form of monohydrated and nonhydrated species; Ca²⁺ binding in the central part of the ligand induces the formation of the monohydrated state. The increasing hydration number accounts for the relaxivity increase observed on Ca²⁺ addition. A ¹H nuclear magnetic relaxation dispersion and ¹⁷O NMR study on Gd₂L¹ in the absence and in the presence of Ca²⁺ was performed to assess the microscopic parameters influencing relaxivity. On Ca²⁺ binding, the water exchange is slightly accelerated, which is likely related to the increased steric demand of the central part leading to a destabilization of the Ln–water binding interaction.

Selective estrogen receptor modulation: the search for an ideal hormonal therapy for breast cancer

Female hormones, especially estrogens, play an important role in the pathogenesis of breast neoplasms and are a principal determinant of their biological behavior. Endocrine manipulation through medical or surgical means can often lead to objective shrinkage of breast tumors. Tamoxifen, a triphenylethylene estrogen receptor modulator, is currently the most widely used hormonal treatment for breast cancer. It has been conclusively demonstrated to reduce the risk of relapse following definitive local therapy (and systemic chemotherapy, when indicated) of invasive or noninvasive breast cancer. Recently, it has also been shown to reduce the incidence of breast cancer in healthy women who are at high risk of developing the disease. In addition, it can prevent osteoporosis and reduce the risk of fractures in postmenopausal women. However, its use is also complicated by an increased incidence of endometrial hyperplasia/carcinoma, venous thromboembolism, cataracts, and in some cases, emergence of tamoxifen-dependent clones of breast cancer. These side effects (except cataracts) are believed to be related to estrogen-agonist effects of tamoxifen. Newer drugs, which are "pure antiestrogens" or inhibitors of estrogen biosynthesis, are devoid of such estrogen-agonist activity and may not have the liability of many of these side effects. However, these agents would also be expected to lack the potentially beneficial effects of tamoxifen on lipids and skeletal system. The ability of tamoxifen to act as an estrogen-agonist or estrogen-antagonist in a tissue-specific fashion has led to the concept of selective estrogen-receptor modulation. Selective estrogen receptor modulators (SERMs), which are devoid of estrogen-agonist effects on the uterus or breast cancer cells but retain potentially beneficial effects on bones and lipids, have been described as "ideal" SERMs. A number of such compounds are currently being tested. Raloxifene is already approved for prevention of osteoporosis and has potential efficacy for prevention and treatment of breast cancer. An analogue of raloxifene, LY353381, is currently in Phase II clinical trials for treatment of breast cancer, with promising early results. EM800 and CP336156 are other promising ideal SERMs in clinical trials. These compounds may provide better treatment and chemoprevention alternatives for breast cancer as compared to tamoxifen, aromatase inhibitors, and pure antiestrogens. In addition, they may also prove to be useful for the treatment and prevention of prostate cancer as well as for treating benign gynecological diseases such as fibroids and endometriosis. Future laboratory efforts should focus on further broadening the efficacy profile of SERMs (e.g., prevention of Alzheimer's disease and elevation of high-density lipoproteins to improve the likelihood of cardiovascular benefit) and narrowing their side-effect profile (e.g., risk of thromboembolism and hot flashes).

Phase I study of a third-generation selective estrogen receptor modulator, LY353381.HCL, in metastatic breast cancer

PURPOSE

We conducted this phase I trial to determine the safety and toxicity profile of LY353381.HCl-a novel, potent, third-generation selective estrogen receptor modulator (SERM)-because this benzothiophene derivative demonstrated an SERM profile in preclinical studies.

PATIENTS AND METHODS

We studied 32 patients with recurrent or metastatic breast cancer. Patients were treated in four cohorts with oral daily doses of 10, 20, 50, and 100 mg. Pharmacokinetic sampling was performed during the first 72 hours following the first dose on day 1 and during the 24 hours after the day 57 dose. Eligibility criteria included Eastern Cooperative Oncology Group performance status of 0 to 2; no significant major organ dysfunction; and at least 3 weeks elapsed since most recent hormonal therapy, chemotherapy, and estrogen replacement therapy.

RESULTS

The median patient age was 56 years (range, 30 years to 76 years). The median number of prior chemotherapies for metastatic disease was one (range, zero to four), while the median number of prior hormone regimens for metastatic disease was two (range, zero to five). Receptor status was estrogen receptor (ER) positive and progesterone receptor (PR) positive, 19 patients; ER positive and PR negative, eight patients; ER positive and PR unknown, two patients; and ER and PR unknown, three patients. Dose-limiting toxicity was not observed. Treatment was well tolerated with mild to moderate hot flashes in 18 of 32 patients (56%) at all dose levels. Transvaginal ultrasound performed at baseline and after 12 weeks of treatment showed no endometrial thickening. Of the 32 patients evaluable for response, six patients had stable disease for at least 6 months with a median duration of 7.7 months (range, 6.2 months to 33.8 months). The pharmacokinetics of LY353381.HCl were generally linear with respect to time and studied dose range.

CONCLUSION

As predicted in preclinical testing, daily oral LY353381.HCl is safe, is well tolerated at all tested dose levels, and may be clinically beneficial in patients with extensively pretreated metastatic breast cancer. Further studies with LY353381 to evaluate the efficacy in patients with or without prior exposure to tamoxifen and fewer overall prior regimens are under way.

Quantitative nuclear morphometry by image analysis for prediction of recurrence of ductal carcinoma in situ of the breast

Clinical management of ductal carcinoma in situ (DCIS) remains a challenge because significant proportions of patients experience recurrence after conservative surgical treatment. Unfortunately, it is difficult to prospectively identify, using objective criteria, patients who are at high risk of recurrence and might benefit from additional treatment. We conducted a multi-institutional, collaborative case-control study to identify nuclear morphometric features that would be useful for identifying women with DCIS at the highest risk of recurrence. Tissue sections of archival breast tissue of 29 women with recurrent and 73 matched women with nonrecurrent DCIS were stained for DNA, and nuclei in the DCIS lesions were evaluated by image analysis. A clear correlation between mean fractal2_area (FA2) and nuclear grade was observed (P < 0.001), allowing an objective determination of nuclear grade. Several nuclear morphometric features, including mean and variance of variation of radius, mean area, mean and variance of frequency of high boundary harmonics (FQH), and variance in sphericity, were found to be useful in discriminating recurrent from nonrecurrent DCIS subjects. However, the nuclear features associated with recurrence differed between high- and low-grade lesions. For lesions with high FA2 (nuclear grade 3), mean variation of radius, mean FQH, and mean area alone yielded recurrence odds ratios of 4.55 [95% confidence interval (CI) 0.45-45.96], 3.86 (95% CI, 0.88-16.98), 2.90 (95% CI, 0.31-27.2), respectively. Using a summed feature model, high-FA2 lesions showing three poor prognostic features had an odds ratio of 15.63 (95% CI, 1.22-200), compared with those with zero or one poor prognostic feature. Lesions with low mean FA2 (nuclear grade 1 or 2) showing high variances in sphericity and FQH had an odds ratio of 7.71 (95% CI, 1.77-33.60). Addition of other features did not enhance the odds ratio or its significance. These results suggest that nuclear image analysis of DCIS lesions may provide an adjunctive tool to conventional pathological analysis, both for the objective assessment of nuclear grade and for the identification of features that predict patient outcome.

Phase I study of vinorelbine and paclitaxel by 3-hour simultaneous infusion with and without granulocyte colony-stimulating factor support in metastatic breast carcinoma

BACKGROUND

The purpose of the study was to determine the maximum tolerated dose (MTD) of vinorelbine and paclitaxel given concomitantly in patients with advanced breast carcinoma, the toxicity of this combination, and whether the addition of granulocyte colony-stimulating factor (G-CSF) would allow administration of higher doses of the combination.

METHODS

Between January 1994 and January 1995, 38 patients were entered on this study. All patients received vinorelbine and paclitaxel administered simultaneously over 3 hours and repeated every 21 days as frontline therapy for metastatic breast carcinoma. Twenty-five patients (Group 1) did not receive prophylactic G-CSF, and 13 patients (Group 2) received prophylactic G-CSF. Toxic effects were documented prospectively using the National Cancer Institute grading system.

RESULTS

One hundred eighty-seven (Group 1) and 111 (Group 2) cycles were administered. For Group 1, Grade 3-4 granulocytopenia was encountered in 72% of the cycles and neutropenic fever in 30% of the cycles. For Group 2, Grade 3-4 granulocytopenia and neutropenic fever were encountered in 23% and 4% of the cycles, respectively. Grade 3-4 fatigue and myalgia, respectively, were encountered in 11% and 3% of the cycles in Group 1, whereas they were reported in 12% and 1% of the cycles in Group 2. The MTD of this combination without prophylactic G-CSF was 25 mg/m2 of vinorelbine and 150 mg/m2 of paclitaxel, the dose-limiting toxicity (DLT) being neutropenic fever and myalgia. The MTD of this combination with G-CSF was 36 mg/m2 of vinorelbine and 150 mg/m2 of paclitaxel, the DLT being myalgia and fatigue.

CONCLUSIONS

The authors conclude that vinorelbine and paclitaxel can be safely administered concomitantly and are well tolerated. Phase II studies are recommended to test the efficacy of this schedule.

Phase II study of paclitaxel in patients with metastatic breast carcinoma refractory to standard chemotherapy

BACKGROUND

The authors conducted a single institution Phase II clinical trial to determine whether paclitaxel had antitumor activity in patients with metastatic breast carcinoma that was refractory to standard chemotherapy.

METHODS

Patients with metastatic breast carcinoma were eligible for the study if they had disease progression after at least 2 prior chemotherapy regimens. Patients who had received three prior regimens were treated in a separate cohort. All patients were required to have received doxorubicin in the past and were not eligible if they had received prior therapy with paclitaxel. The starting dose of paclitaxel for low risk patients was 175 mg/m2, administered as a 24-hour continuous infusion; the starting dose of paclitaxel was 150 mg/m2 for patients who had received > or = 3 prior regimens. Therapy was given every 3 weeks and continued for at least 2 courses unless there was evidence of rapidly progressing disease, for at least 3 courses if there was no change in disease and Grade 3 or 4 (based on National Cancer Institute toxicity criteria) toxicity was not noted, and for 6 courses beyond the maximum response in patients who demonstrated complete or partial responses and showed no evidence of disease progression.

RESULTS

Sixty-eight of 69 patients entered in the study were evaluable for response: 35 patients who had received 2 prior chemotherapy regimens for Stage IV disease and 33 patients who had received > or =3 prior regimens. A partial response was observed in 7 patients who had received 2 prior regimens, for an objective response rate of 20% (95% confidence interval [95% CI], 14-26%). In the group who had received > or = 3 prior regimens, a total of 6 partial responses were observed, for an objective response rate of 18% (95% CI, 12-23%). The median response duration was 8.2 months (range, 2.7-10.1 months) for the group who had received 2 prior regimens and 5.8 months (range, 2.1-9.5 months) for patients who received > or = 3 prior regimens. Responses were noted in patients with anthracycline-resistant tumors.

CONCLUSIONS

Paclitaxel was active in heavily pretreated patients with metastatic breast carcinoma, including anthracycline-resistant breast carcinoma.

Antiestrogens--tamoxifen, SERMs and beyond

Estrogens play a central role in reproductive physiology. The cellular effects of estrogens are mediated by binding to nuclear receptors (ER) which activate transcription of genes involved in cellular growth control. At least two such receptors, designated ERalpha and ERbeta, mediate these effects in conjunction with a number of coactivators. These receptors can directly interact with other members of the steroid receptor superfamily. A complex cross-talk exists between the estrogen-signaling pathways and the downstream signaling events initiated by growth factors, such as epidermal growth factor and insulin-like growth factors. Estrogens are also a causative factor in the pathogenesis of a variety of neoplastic and non-neoplastic diseases, including breast cancer, endometrial cancer, endometriosis, and uterine fibroids, among others. Antiestrogens, such as tamoxifen, are widely used for the treatment of breast cancer. Tamoxifen produces objective tumor shrinkage in advanced breast cancer, reduces the risk of relapse in women treated for invasive breast cancer, and prevents breast cancer in high-risk women. Although, initially developed as an antiestrogen, tamoxifen can also prevent postmenopausal osteoporosis as well as reduce cholesterol, due to its estrogen-agonist effects. Its estrogen-agonist activity, however, can lead to significant side-effects such as endometrial cancer and thromboembolic phenomena. This has led to the concept of "ideal" selective estrogen receptor modulators (SERMs), drugs that would have the desired, tissue selective, estrogen-agonist or -antagonist effects. Raloxifene is a SERM which has the desirable mixed agonist/antagonist effects of tamoxifen but does not cause uterine stimulation. "Pure" antiestrogens may provide very potent estrogen-antagonist drugs, but are likely to be devoid of beneficial effects on bone and lipids. Future drug development efforts should focus on developing superior SERMs that have a greater efficacy against ER-positive tumors and do not cause hot flashes or thromboembolism, and explore combination strategies to simultaneously target hormone-dependent as well as hormone-independent breast cancer.

Interobserver reproducibility of the Lagios nuclear grading system for ductal carcinoma in situ

Several studies have shown an association between high nuclear grade or necrosis of ductal carcinoma in situ (DCIS) lesions and the risk of local disease recurrence in patients with DCIS treated surgically with less than mastectomy. Although criteria for separating low from high nuclear grade lesions have been published, no information exists regarding interobserver reproducibility (IR). To assess IR in the classification of DCIS, six surgical pathologists from four institutions used the Lagios grading system to grade 125 DCIS lesions. Before meeting to evaluate the cases, a training set of 12 glass slides, including cases chosen to present conflicting cues for classification, was mailed to the participants with a written criteria summary. This was followed by a working session in which criteria were reviewed and agreed on. The pathologists then graded the lesions independently. The area of interest was marked on each slide before grading. After initial grading, the pathologists met again to resolve discrepant lesion classifications. A complete agreement among raters was achieved in 43 (35%) cases, with five of six raters agreeing in another 45 (36%) cases. In no case did two raters differ by more than one grade. The pairwise kappa agreement values ranged from fair to substantial (0.30 to 0.61). Generalized kappa value indicated moderate agreement (0.46, standard error = 0.02). Kappa statistics for the distinction between grades 1 and 2 and 2 and 3 were 0.29 and 0.48, respectively, (standard error = 0.02). Only one of the six raters differed significantly in scoring. With adherence to specific criteria, IR in the classification of DCIS cases can be obtained in most cases. Although these pathologists made a few grading system modifications, further refinements are needed, especially if grading will influence future therapy.

Clinical course of breast cancer patients with complete pathologic primary tumor and axillary lymph node response to doxorubicin-based neoadjuvant chemotherapy

PURPOSE

To assess patient and tumor characteristics associated with a complete pathologic response (pCR) in both the breast and axillary lymph node specimens and the outcome of patients found to have a pCR after neoadjuvant chemotherapy for locally advanced breast cancer (LABC).

PATIENTS AND METHODS

Three hundred seventy-two LABC patients received treatment in two prospective neoadjuvant trials using four cycles of doxorubicin-containing chemotherapy. Patients had a total mastectomy with axillary dissection or segmental mastectomy and axillary dissection followed by four or more cycles of additional chemotherapy. Patients then received irradiation treatment of the chest-wall or breast and regional lymphatics. Median follow-up was 58 months (range, 8 to 99 months).

RESULTS

The initial nodal status, age, and stage distribution of patients with a pCR were not significantly different from those of patients with less than a pCR (P>.05). Patients with a pCR had initial tumors that were more likely to be estrogen receptor (ER)-negative (P<.01), and anaplastic (P = .01) but of smaller size (P<.01) than those of patients with less than a pCR. Upon multivariate analysis, the effects of ER status and nuclear grade were independent of initial tumor size. Sixteen percent of the patients in this study (n = 60) had a pathologic complete primary tumor response. Twelve percent of patients (n = 43) had no microscopic evidence of invasive cancer in their breast and axillary specimens. A pathologic complete primary tumor response was predictive of a complete axillary lymph node response (P<.01 ). The 5-year overall and disease-free survival rates were significantly higher in the group who had a pCR (89% and 87%, respectively) than in the group who had less than a pCR (64% and 58%, respectively; P<.01).

CONCLUSION

Neoadjuvant chemotherapy has the capacity to completely clear the breast and axillary lymph nodes of invasive tumor before surgery. Patients with LABC who have a pCR in the breast and axillary nodes have a significantly improved disease-free survival rate. However, a pCR does not entirely eliminate recurrence. Further efforts should focus on elucidating the molecular mechanisms associated with this response.

Residual metastatic axillary lymph nodes following neoadjuvant chemotherapy predict disease-free survival in patients with locally advanced breast cancer

BACKGROUND

This study was performed to validate the prognostic significance of residual axillary lymph node metastases in patients with locally advanced breast cancer (LABC) treated with neoadjuvant chemotherapy and to analyze other clinicopathologic factors that might be independent predictors of disease-free survival (DFS) in an attempt to identify patients in whom axillary dissection might be omitted.

METHODS

One hundred sixty-five assessable patients with LABC were treated in a prospective trial of neoadjuvant chemotherapy utilizing four cycles of 5-fluorouracil, doxorubicin, and cyclophosphamide. Responding patients were treated with segmental mastectomy and axillary dissection or modified radical mastectomy. Patients subsequently received additional chemotherapy followed by irradiation of the breast or chest wall and draining lymphatics. The median follow-up was 35 months.

RESULTS

Clinical tumor response to neoadjuvant chemotherapy (P = 0.046) and the number of residual metastatic axillary lymph nodes found at axillary dissection (P = 0.05) were the only independent predictors of DFS. Patients with a complete clinical response had a predictably excellent DFS and those with no change or progressive disease had a poor DFS. In patients with a partial response, the number of residual metastatic lymph nodes further stratified patients with respect to DFS (P = 0.006).

CONCLUSIONS

Clinical response and residual metastatic axillary lymph nodes following neoadjuvant chemotherapy are important predictors of DFS. Patients with a clinically positive axilla following neoadjuvant chemotherapy should undergo axillary dissection to ensure local control. However, the benefit of axillary dissection in patients with a clinically negative axilla may be minimal if the axilla will be irradiated, and histologic staging does not affect subsequent systemic treatment. A prospective randomized trial of axillary dissection versus axillary radiotherapy in patients with a clinically negative axilla following neoadjuvant chemotherapy is presently under way to evaluate this hypothesis.

Role of axillary lymph node dissection after tumor downstaging with induction chemotherapy for locally advanced breast cancer

BACKGROUND

Induction chemotherapy has become the standard of care for patients with locally advanced breast cancer (LABC) and currently is being evaluated in prospective clinical trials in patients with earlier-stage disease. To better gauge the role of axillary lymph node dissection in patients with LABC this study was performed to assess initial axillary status on physical and ultrasound examination, axillary tumor downstaging following induction chemotherapy, and the accuracy of physical examination compared with axillary sonography in predicting which patients will have axillary lymph node metastases found on pathologic examination.

METHODS

Between 1992 and 1996, 147 consecutive patients with LABC were registered in a prospective trial of induction chemotherapy using 5-fluorouracil, doxorubicin, and cyclophosphamide. Physical and ultrasound examinations of the axilla were performed at diagnosis and after induction chemotherapy. Segmental resection with axillary lymph node dissection or modified radical mastectomy was performed, followed by postoperative chemotherapy and irradiation of the breast or chest wall and regional lymphatics.

RESULTS

Following induction chemotherapy, 43 (32%) of the 133 patients with clinically positive lymph nodes on initial examination had axillary tumor downstaging as assessed by physical and ultrasound examination. The sensitivity of axillary sonography in identifying axillary metastases was significantly higher than that of physical examination (62% vs. 45%, P=.012). The specificity of physical examination (84%) was higher than that of sonography (70%), but the difference did not reach statistical significance. Among the 55 patients in whom the findings of both physical and ultrasound examination of the axilla were negative following induction chemotherapy, 29 patients (53%) were found to have axillary lymph node metastases on pathologic examination of the axillary contents. However, 28 (97%) of these patients had either 1 to 3 positive lymph nodes or only micrometastases 2 to 5 mm in diameter.

CONCLUSIONS

Preoperative clinical assessment of the axilla by physical examination combined with ultrasound examination is not completely accurate in predicting metastases in patients with LABC following tumor downstaging. However, patients with negative findings on both physical and ultrasound examinations of the axilla may be potential candidates for omission of axillary dissection if the axilla will be irradiated because minimal axillary disease remains. Patients who have positive findings on preoperative physical or ultrasound examinations should receive axillary dissection to ensure local control. A prospective randomized trial of axillary dissection versus axillary radiotherapy in patients with a clinically negative axilla following induction chemotherapy is currently underway.

Pathologic tumor response in the breast following neoadjuvant chemotherapy predicts axillary lymph node status

PURPOSE

Neoadjuvant chemotherapy is becoming the standard of care for locally advanced breast cancer. This study was performed to determine whether pathologic primary tumor response to neoadjuvant chemotherapy might predict axillary lymph node status and so be used to identify patients in whom surgery could be effectively limited to biopsy of the previous primary tumor site without axillary dissection.

PATIENTS AND METHODS

Between 1992 and 1996, 170 consecutive patients with locally advanced breast cancer were treated in a prospective trial with four preoperative cycles of 5-fluorouracil, doxorubicin, and cyclophosphamide. Disease was staged before initiation of preoperative chemotherapy and before surgery. Segmental resection with axillary lymph node dissection or modified radical mastectomy was performed first, followed by postoperative chemotherapy and radiation therapy of the breast (or chest wall) and regional lymphatics. Patient and tumor characteristics associated with complete versus incomplete pathologic primary tumor response to neoadjuvant chemotherapy and correlation between primary breast tumor pathologic response and axillary lymph node status found at surgery were analyzed.

RESULTS

Of 156 evaluable patients, 30 patients (19%) had primary breast tumors that were completely eliminated after induction chemotherapy based on histologic assessment. Nineteen of those 30 patients (63%) had negative axillary lymph nodes at dissection, compared with 13 patients (33%) of the 40 who had a near-complete pathologic primary tumor response (< or = 1 cm3 remaining) and only 15 patients (17%) of the 86 who had > 1 cm3 tumor remaining in the pathology specimen of the breast primary. Of the 22 patients with a complete pathologic response in the breast and a clinically negative axilla after induction chemotherapy, axillary dissection revealed positive lymph nodes in four. These four patients had only one or two positive lymph nodes.

DISCUSSION

Because initial clinical regression of primary tumor with neoadjuvant chemotherapy is considered an excellent prognostic indicator and because patients with locally advanced breast cancer routinely receive local and regional radiation treatment followed by additional chemotherapy, the role of breast and axillary surgery has been questioned. In this study, a complete pathologic response of the primary tumor to induction chemotherapy is highly predictive of negative axillary lymph node status. Therefore, axillary lymph node dissection may be omitted in certain subsets of patients who have a biopsy-proven complete pathologic response in the primary tumor and a clinical negative axillary examination. Further prospective, randomized investigation is needed to confirm this finding.

Expression of leukemia inhibitory factor and its receptor in breast cancer: a potential autocrine and paracrine growth regulatory mechanism

Leukemia inhibitory factor (LIF) is a pluripotent cytokine which has a diverse array of effects on hematopoietic and epithelial cells. Depending on the nature of the target cells, these effects can be growth-stimulatory or growth-inhibitory. Receptors for leukemia inhibitory factor (LIFR) have been identified on a variety of hematopoietic and epithelial cells. We have recently demonstrated in vitro growth stimulation of human breast cancer cells, both primary tumors and cultured cell lines, by LIF. To begin to understand the in vivo relevance of these observations, we investigated the expression of LIF and LIFR in human breast cancer specimens. Specimens from 50 cases were immunostained with mouse monoclonal antibodies D62.3 and M1 (to stain for LIF and LIFR, respectively). LIF expression was observed in 78% of the specimens and correlated with favorable biological features, i.e. low S-phase fraction (SPF) (P = 0.001) and diploidy (P = 0.08). LIFR expression was observed in 80% of the tumors and correlated with the presence of estrogen receptor (ER) (P = 0.04) and diploidy (P = 0.07). Coexpression of LIF and LIFR was associated with diploidy (P = 0.02) and low SPF (P = 0.05). LIF staining was primarily cytoplasmic whereas LIFR staining was cytoplasmic in the majority of cases and membranous in a minority of cases. The presence of LIFR in the primary tumor specimens correlated with the growth stimulation of tumor cells (derived from the same specimens) by exogenous LIF in methylcellulose colony assays. The findings support a widespread but probably complex role for LIF and LIFR in breast tumor growth regulation which should be investigated in greater detail in larger cohorts of tumors.

The prognostic significance of sialyl-Tn antigen in women treated with breast carcinoma treated with adjuvant chemotherapy

BACKGROUND

Sialyl-Tn (STn) represents an aberrantly glycosylated mucin epitope that is expressed in breast carcinoma and other adenocarcinomas and is an important factor in the development of novel immunotherapeutic approaches. The primary aim of the current study was to investigate the influence of STn expression on the prognoses of patients with breast carcinoma.

METHODS

A cohort of 207 women diagnosed with invasive breast carcinoma who were treated with anthracycline-containing adjuvant chemotherapy and were enrolled in a randomized clinical trial were studied. Expression of STn was determined by an immunohistochemical procedure in which the B72.3 monoclonal antibody was used. Kaplan-Meier and Cox proportional regression survival analyses were used to compare low STn and high STn patients.

RESULTS

Forty-eight (23%) of the 207 specimens demonstrated high STn staining (>25% cells were immunoreactive). During a median follow-up of 5 years, high STn patients had worse disease free survival than low STn patients (55% vs. 74%, respectively; P = 0.03). High STn expression was significantly associated with age (P = 0.04) but not with other conventional prognostic markers. In multivariate analysis using the Cox regression model, high STn emerged as an independent prognostic indicator for disease free survival (hazard ratio [HR], 2.02; 95% confidence interval [CI], 1.09-3.73) and for overall survival (HR, 2.16; 95% CI, 0.95-4.92).

CONCLUSIONS

The results of this study suggest that STn may be a valuable marker for identifying women at high risk of developing recurrent breast carcinoma who may be candidates for trials investigating new therapies in combination with standard adjuvant therapy.

Progressive decrease in nuclear retinoic acid receptor beta messenger RNA level during breast carcinogenesis

Some of the nuclear retinoic acid receptors (RARs) alpha, beta, and gamma and retinoid X receptors (RXRs) alpha, beta, and gamma are thought to mediate the effects of retinoids on cell growth, differentiation, and apoptosis and thereby prevent breast carcinogenesis. We analyzed the expression of mRNAs for the three RARs and RXR-alpha in histological sections of specimens from 70 breast cancer patients, which included adjacent normal tissue, ductal carcinoma in situ, and invasive cancer, using in situ hybridization. RARs alpha, beta, and gamma and RXR-alpha were expressed in 98.1, 98.0, 93.0, and 100% of the adjacent normal tissues. Significant decreases in the number of cases expressing RAR-beta were observed among ductal carcinoma in situ (83.1%) and invasive carcinomas (51.6%), especially among the poorly differentiated cases (77.4 and 35.7 %, respectively). No relationship was found between the expression of estrogen receptor and RAR-beta. These results implicate decreases in RAR-beta expression in breast cancer development and suggest that they are independent of estrogen receptor status.

Lipid peroxidation-induced putative malondialdehyde-DNA adducts in human breast tissues

The etiology of the majority of human breast cancers is unknown; however, oxidative stress and lipid peroxidation have been suggested to play a role in breast carcinogenesis. To address this possibility, DNA adducts induced by malondialdehyde (MDA), an end product of lipid peroxidation, were analyzed in surgical specimens of normal breast tissues of 51 breast cancer patients using the nuclease P1-enhanced version of the 32P-postlabeling assay. Normal breast tissue samples from 28 noncancer patients receiving reduction mammoplasty served as controls. Two previously characterized putative MDA-deoxyadenosine (dA) and one MDA-deoxyguanosine adduct were detected in all tissue samples examined. Normal breast tissues from cancer patients exhibited significantly higher levels of the putative MDA adducts [median (42.5) and range (2.2-202.8) of relative adduct labeling x 10(9) values] than those found in noncancer controls (median, 15.67; range, 2.4-382.1; P = 0.0001, Mann-Whitney U test). Ten of the 51 cancer patients and 1 of the 28 controls were found to contain the putative MDA adducts at the level of > 1/10(7) nucleotides, a frequency comparable to that found in human liver. Age and body mass did not significantly influence the levels of these adducts. However, the presence of a previously detected benzo(a)pyrene-like DNA adduct in the breast tissues was associated with higher levels of the putative MDA-dA adducts in cancer patients (P = 0.012). The level of the putative MDA-dA adducts was significantly lower in smokers and former smokers compared to nonsmokers among cases after adjusting for age, body mass index, and status of the benzo(a)pyrene-like adduct (P = 0.009). Tumor tissues (n = 11) displayed significantly lower levels of the putative MDA adducts (median, 10.2; range, 5.3-20.6) than their corresponding normal adjacent tissues (median, 25.5; range, 10.5-138; P < 0.01). These findings provide evidence that lipid peroxidation products can accumulate in human breast tissues and reach relatively high levels in the breast tissues of women with breast cancer. There seems to be an interaction between these endogenous DNA modifications and carcinogen exposure-induced DNA adducts. Detection and quantitation of the putative MDA-DNA adducts may potentially be a useful tool in the understanding of breast cancer etiology.

Critical evaluation of prognostic factors

The ability to predict the biological behavior of breast tumors can allow selection of the optimum treatment and follow-up strategies. Conventionally, tumor size, lymph node metastases, and histopathologic features have been used to determine the risk of systemic relapse. The discovery of a number of specific genetic and biochemical alterations in breast tumors has led to the molecular era of prognostic factors. Many of these molecular changes are determinants of relevant biological characteristics of malignancy, ie, dyregulated proliferation, invasion, and metastases. Preliminary data suggest that they may provide a better determination of the risk of relapse than can be ascertained by conventional prognostic factors alone. For example, amplification/overexpression of HER-2/neu oncogene has been shown to be a marker of increased risk of relapse after locoregional therapy of breast cancer. More recent studies have shown that it may also play a role in determining sensitivity to chemo-therapeutic drugs. It is expected that a greater understanding of the molecular basis of breast cancer growth regulation will allow a better identification of subjects who should receive systemic therapy and will also allow a better selection of the appropriate systemic therapy regimen.

Technical approach for the study of the genetic evolution of breast cancer from paraffin-embedded tissue sections

We have optimized a technique that allows the study of numerous chromosomal loci (n = 20-50) from single paraffin-embedded tissue sections by microsatellite length polymorphism analysis. DNA samples from normal and breast cancerous tissue can be obtained from the same section by means of microdissection. This technique was further improved by subjecting DNA to several cycles of amplification with a degenerate (universal) primer and then with specific microsatellite primers. This amplified DNA was also used to screen for mutations in the p53 gene by means of PCR-SSCP. In addition adjacent tissue sections were used to assess specific chromosome copy number by interphase cytogenetic analyses (chromosome in situ hybridization) and to analyze expression of specific genes such as p53 and ERBB2. As an example of the use of our approach we performed a detailed chromosome 17 allelotypic analysis in 22 breast tumors (5 ductal carcinomas in situ, 13 invasive ductal carcinomas, and 4 invasive lobular carcinomas). We detected mutations in the p53 gene by PCR-SSCP in 36% of the samples. Samples with significant levels of p53 protein accumulation detected by immunohistochemistry were also positive for mobility shifts in the SSCP analysis. We observed that chromosome 17 allelic losses and imbalance occurred at as early a stage as ductal carcinoma in situ (DCIS). Although in some cases we observed allelic losses or imbalance affecting the 17p13 region, close to the p53 locus, several of the tumors showed dissociation between such loss or imbalance and p53 mutation. Lobular carcinomas were predominantly disomic for chromosome 17 in contrast with ductal tumors, which often showed polysomy for chromosome 17. This comprehensive approach correlating the tumor subtype, its allelotype, with specific chromosome copy number and specific gene mutations and expression in preinvasive or early invasive breast cancer lesions will potentially provide information of relevance for a better understanding of the multistep mechanisms of breast carcinogenesis.

Paclitaxel: severe mucocutaneous toxicity in a patient with hyperbilirubinemia

Paclitaxel is a novel anticancer drug that is being increasingly used to treat cancer of the breast and other organs. We describe a patient with metastatic breast cancer and liver dysfunction who had severe mucocutaneous toxicity after administration of a standard dose of paclitaxel. Another interesting finding in this patient was that the administration of paclitaxel led to a prompt resolution of parathyroid hormone-related protein (PTHrP)-mediated hypercalcemia, which had previously proven to be refractory to multiple conventional antihypercalcemic agents as well as anthracycline-containing chemotherapy combination. The need for definitive guidelines for paclitaxel administration in the setting of hepatic dysfunction and the potentially unique sensitivity of PTHrP--producing cells to paclitaxel are discussed.

Aromatic DNA adducts in adjacent tissues of breast cancer patients: clues to breast cancer etiology

The etiology of the majority of human breast cancers is unknown. Environmental factors have long been suspected to play a role, but no specific causative agent has been identified. If the hypothesis that environmental carcinogen exposure contributes to human breast cancer is true, carcinogen-DNA adducts would be expected to be present in human breast tissues. To address this possibility, aromatic DNA adducts were measured in 87 surgical specimens of normal human breast tissues from 87 breast cancer patients undergoing mastectomy using the nuclease P1-enhanced version of the 32P postlabeling assay. Breast tissue samples from 29 noncancer patients undergoing reduction mammoplasty served as controls. Whereas aromatic DNA adducts were detected in all tissue samples examined, the total adduct levels in cancer patients were significantly higher than that in noncancer controls [mean +/- SEM, 97.4 +/- 23.4/10(9) nucleotides (range, 3.8-1737.1) versus 18.1 +/- 11.6/10(9) nucleotides (range, 5.6-56.7), respectively; P < 0.01, t test and Mann-Whitney test]. This difference was not affected by the age distribution of the two groups. The typical smoking-related DNA adduct pattern (i.e., a diagonal radioactive zone) was observed in 29 of 87 tissues (17 of 17 current smokers, 5 of 8 former smokers, 4 of 52 nonsmokers, and 3 of 10 patients with unknown smoking status) and in 2 of 10 control tissues. It was of interest that a benzo(a)pyrene (BP)-like DNA adduct was observed in 36 normal adjacent breast tissues (41%), 27 of which were from nonsmokers. Levels of this BP-like adduct were extremely high (> 100/10(9) nucleotides) in 5 patients (4 nonsmokers and 1 smoker) and moderately high (> 10/10(9) nucleotides) in 13 other patients (8 nonsmokers and 5 smokers). One patient exhibited this adduct at a level of 1500/10(9) nucleotides, which is comparable to the highest level of total adducts reported in human tissues related to carcinogen exposure (e.g., cigarette smoking). In contrast, this adduct was absent (< 1/10(9) nucleotides) in all of the control tissues. Cochromatography and rechromatography analysis of DNA samples from human breast tissues and from MCF-7 cells treated with BP revealed that this adduct could be generated by BP exposure but is not the major BP 7,8-diol-9,10-epoxide-deoxyguanine adduct detected previously in animal tissues and human mammary epithelial cells. These findings support the hypothesis that environmental carcinogen exposure, in addition to cigarette smoking, may be associated with the etiology of human breast cancer.

The effects of anaemia on heart, placenta and body weight, and blood pressure in fetal and neonatal rats

1. Reports that maternal anaemia in pregnancy is associated with a greater placental: birth weight ratio, which predisposes towards high postnatal blood pressure in the human, led us to examine the effects of maternal anaemia during pregnancy on placental size, fetal and neonatal growth, and blood pressure development in the rat. 2. Nutritional anaemia was induced in female rats prior to mating and maintained throughout pregnancy and up until weaning of the pups. Fetuses were studied at 20 days of gestation (E20). Pups were studied on postnatal days 20 (P20) and 40 (P40), having been weaned onto normal rat chow at 21 days. 3. In the anaemic group placental: fetal body weight ratios were lower compared with controls. Body weights at all ages were lower in the anaemic group than in controls, despite a greater rate of growth in the anaemic group between P20 and P40. 4. At P20 heart weights of the anaemic group were almost twice that of controls, suggesting an alteration in their cardiovascular development. However, paradoxically, the systolic blood pressure of the anaemic group was lower than that of controls. 5. By P40 the systolic blood pressure of the anaemic group (136 +/- 3 mmHg) had increased and was greater than that in control pups (126 +/- 3 mmHg). 6. In conclusion, we have shown that there is a pronounced postnatal rise in systolic blood pressure associated with maternal anaemia during pregnancy, which is not related to a greater placental: birth weight ratio. Before weaning, anaemic pups have a lower systolic blood pressure than controls and there is an important association between the rate of postnatal growth and blood pressure.

Phase I clinical and pharmacological study of suppression of human antimouse antibody response to monoclonal antibody L6 by deoxyspergualin

Development of human antimouse antibody (HAMA) is a major limiting factor in the application of murine mAb for clinical use. A novel immunomodulatory drug, deoxyspergualin (DSG), has shown potential to suppress antimouse antibody response in preclinical model systems. We conducted a Phase I trial to determine the effect of DSG on HAMA response to murine mAb L6 administered to patients with advanced cancers (in previous trials, this antibody elicited HAMA in two-thirds of the treated patients). L6 mAb was administered at a fixed dose of 200 mg/m2 on days 1-5. DSG was administered at doses of 50 mg/m2 [dose level (dl) 1] or 150 mg/m2 (dls II and III) on days 1-7. Treatment courses were repeated every 6 weeks (dls I and II) or every 3 weeks (dl III). HAMAs were quantitated by a commercially available ELISA assay (ImmuSTRIP; anti-isotypic antibodies) and a radiometric assay (antiisotypic and anti-idiotypic antibodies). Pharmacokinetics of L6 and DSG was also studied in all consenting patients. Among 24 evaluable patients, 2 patients developed detectable HAMAs using the ELISA (one each at dls I and II) after a median follow-up of 122 days (P = 0.0001 as compared to historical controls). Even in the two patients who developed HAMA, the HAMA levels were quite low (160 and 181 ng/ml; historical experience, 70-38,744 ng/ml). The radiometric assay detected anti-L6 antibodies in 13 patients (4, 6, and 3 at dls I-III, respectively) after a median of 82 days. The median highest anti-L6 antibody level was 129 ng/ml (range, 21-2150). The highest anti-L6 antibody level at dl III was only 44 ng/ml. The results suggest suppression of anti-idiotypic response also. No clinical antitumor activity was observed, and no significant changes in T4/T8 subsets or immunoglobulins occurred (suggesting a lack of generalized immunosuppression). We conclude that DSG can suppress HAMA response to L6. A starting dose of 150 mg/m2/day is recommended for Phase II trials to confirm this observation.

Phase II clinical and pharmacological study of pirarubicin in combination with 5-fluorouracil and cyclophosphamide in metastatic breast cancer

Doxorubicin containing combination chemotherapy regimens are widely used for treatment of breast and other cancers. However, these regimens are associated with significant toxicities including myocardial dysfunction and alopecia. Analogues of doxorubicin are being developed to reduce these side effects. We conducted a Phase II trial of an anthracycline analogue, pirarubicin, administered in combination with 5-fluorouracil and cyclophosphamide every 3 weeks, as front-line chemotherapy in women with metastatic breast cancer. Patients who had received prior anthracycline therapy were excluded. The chemotherapy doses were as follows: 5-fluorouracil (500 mg/m2 on days 1 and 8), pirarubicin (50 mg/m2 on day 1), and cyclophosphamide (500 mg/m2 on day 1). Among 40 evaluable patients treated on this protocol, a major response (partial or complete remission) was observed in 26 patients (response rate, 62%; 95% confidence interval, 46-77). The median response duration was 8 months, and median survival was 16 months. Grade III/IV myelosuppression occurred in 81% of the courses. The median cumulative pirarubicin dose was 410 (range, 90-870) mg/m2. A significant decrease in left ventricular ejection fraction occurred in 12 patients (at a median cumulative pirarubicin dose of 460 mg/m2) and led to congestive heart failure in 4 of these patients (cumulative pirarubicin doses of 500, 520, 590, and 730 mg/m2, respectively). Eleven patients underwent endomyocardial biopsy, either because they experienced a drop in left ventricular ejection fraction or because they had received a cumulative pirarubicin dose of 600 mg/m2 and were still responding to the treatment. Of these, only one biopsy was found to be more than grade 1.0 (in an individual who had received a cumulative dose of 705 mg/m2). Severe alopecia occurred in two-thirds of the patients. Pharmacokinetic studies revealed a triphasic elimination of pirarubicin with alpha, beta and gamma half-lives of 0.12, 1.44, and 33.9 h, respectively. Total clearance of drug was 4.2 liters.1 h/kg while the cumulative 24-h urinary excretion was less than 10% of the administered dose. The activity of the combination appears to be similar to doxorubicin-containing regimens, while the incidence of alopecia appears to be lower than the historical experience with doxorubicin. However, cardiotoxicity remains a significant problem.

Genetic changes in breast cancer--consequences for therapy?

The knowledge of specific genetic changes and their biological consequences is critical to an understanding of the natural history of breast tumors and the development of rational means to prevent and treat them. A number of genetic changes have been identified in breast tumors. Some of these involve specific genetic loci that directly contribute to one or more attributes of transformation, i.e., dysregulated proliferation and invasion, while other changes confer genetic instability that increases the possibility of acquiring subsequent, specific genetic lesions relevant to tumorigenesis. Many of these changes have been correlated with an adverse prognosis and attempts to integrate these in comprehensive multifactorial prognostic models are in progress. Initial clinical trials have also demonstrated the 'proof of concept' of targeting specific genetic lesions for therapeutic purposes. In the not too distant future, we can envision the use of specific therapies for individual (or subgroups of) tumors based on the specific genetic changes that lead to their development, rather than the global approach of multiagent cytotoxic therapy that is in widespread use today.

A phase II chemoprevention trial design to identify surrogate endpoint biomarkers in breast cancer

Surrogate biomarkers for risk assessment and efficacy of potential chemopreventive agents are needed to improve the efficiency and reduce the cost of conducting chemoprevention trials. In addition to criteria of sensitivity, specificity, quantifiability, and reproducibility applicable to most potential biomarkers, there are additional specific constraints in developing biomarkers for specific organ sites. In the case of breast tissue, these difficulties include lack of a consensus on the nature of premalignant lesions and the histologic criteria used to define them; even when such a consensus can be evolved, there are limitations in visualizing such lesions without invasive biopsies. Also, knowledge of specific genetic and biochemical changes in premalignant lesions is limited. In addition, the physiology of breast tissue is cyclic, no proven, relevant markers can be studied in a randomly obtained needle aspirate. The earliest determinate lesion that can be recognized in breast tissue is ductal carcinoma in situ (DCIS). At the University of Texas M.D. Anderson Cancer Center, we have initiated a study to develop biomarkers for tamoxifen and 4-hydroxyphenylretinamide by administering one or both of these drugs to women with DCIS or small invasive lesions in the interval between the initial diagnostic core biopsy and definitive surgery. The treatment is to be administered for 2-4 weeks. Proposed biomarkers to be studied include: (a) markers associated with neoplastic phenotypes, e.g., excessive proliferation, alternations of nuclear morphology and angiogenesis; (b) proteins likely to be required for response to the putative chemopreventive agents, e.g., estrogen receptor, nuclear retinoid receptors; (c) markers indicative of intact downstream response pathways, e.g., progesterone receptors; (d) oncogenes and tumor suppressor genes regulated by the proposed chemopreventive agents, e.g., neu, TGF-beta; and (e) potential novel markers of genetic instability that could be studied in randomly obtained needle aspirates, i.e., random chromosomal gains and losses in high risk mammary epithelium. The experience gained in designing and conducting this trial is expected to facilitate development of future chemoprevention trials of breast, as well as other organ site cancers.

Sialyl-Tn antigen expression occurs early during human mammary carcinogenesis and is associated with high nuclear grade and aneuploidy

Sialyl-Tn (STn) antigen represents an aberrant glycosylation product of cell surface mucin in adenocarcinomas. We studied its expression in 40 breast carcinomas (35 of which included in situ carcinomas) by performing immunostaining with B72.3 monoclonal antibody. STn expression was observed in 50% of cases and was equally frequent in in situ and in invasive carcinomas. Positive STn staining significantly correlated with high nuclear grade (P = 0.001), aneuploidy (P < 0.001) and high S-phase fraction (P = 0.02). No correlation was observed between STn staining and age, menopausal status, presence of invasive component, or hormone receptor positivity. STn staining may provide an objective marker of dedifferentiation of breast tumors and should be investigated further for its prognostic value in breast cancers and as a biomarker of malignant transformation of breast epithelium.

Quantitative analysis of chromosome in situ hybridization signal in paraffin-embedded tissue sections

Interphase cytogenetic analysis using chromosome-specific probes is increasingly being used to detect chromosomal aberrations on paraffin-embedded tissue sections. However, quantitative analysis of the hybridization signal is confounded by the nuclear slicing that occurs during sectioning. To determine the sensitivity and accuracy of chromosome in situ hybridization for detecting numerical chromosomal aberrations on paraffin-embedded sections, in situ hybridization was performed on sections derived from mixtures of cell populations with known frequencies of numerical chromosomal aberrations and the Chromosome Index (CI) was calculated (i.e., total number of signal spots/number of nuclei counted) as a quantitative measure of chromosome copy number. The presence of 25% or more monosomic or tetrasomic cells in a given population was easily detected as a change in CI (P < 0.05). Lower degrees of polysomy could be detected as a small percentage of nuclear fragments with > 2 signal spots. The CI was not significantly influenced by a change in section thickness from 4 to 8 microM, by an increase in cell size from 478 to 986 microM3, or by the choice of detection method (fluorescence vs. conventional bright-field microscopy). Comparative analysis of touch preparations and tissue sections from the corresponding breast tumors showed that CI accurately reflects the average copy number of chromosomes in intact nuclei and may actually be superior to in situ hybridization on whole nuclei for the detection of numerical chromosomal changes in defined histologic areas. This method is thus a sensitive and accurate means of studying genetic changes in premalignant and malignant tissue, and of assessing the genetic changes associated with specific phenotypes.

Phase II study of deoxyspergualin in metastatic breast cancer

We conducted a phase II trial of the novel immunomodulatory/cytotoxic agent 15-deoxyspergualin in patients with metastatic breast cancer who had failed treatment with front-line chemotherapy. Thirty-eight courses of treatment were administered to fourteen patients enrolled in this trial, 25 at a dose of 1800 mg/m2/d (dose level 0) and 13 at a dose of 2150 mg/m2/d (dose level +1) administered by continuous intravenous infusion for 5 days. Treatment was well tolerated with neuromuscular side-effects (myalgias, paresthesias) and granulocytopenia (nadir granulocyte count of 0.50-0.99 x 10(9)/l) in two and three courses, respectively, as the only grade III toxicities. The neuromuscular toxicity of deoxyspergualin is probably related to the occurrence of hypomagnesemia. No partial or complete responses were observed in this study. One patient achieved a minor response but had progressive disease 65 weeks after enrollment. The response was observed coincident with an increase in T4/T8 ratio in the peripheral blood. The median time to progression for the entire cohort was eight weeks (range, 4-65 weeks). There was no clinical evidence of immunosuppression and no decrease in total peripheral blood lymphocyte counts or helper T-cells was observed. At the doses and schedule employed in this trial, deoxyspergualin does not appear to have significant activity against metastatic breast cancer resistant to front-line chemotherapy. The correlation between hypomagnesemia and neuromuscular toxicity of deoxyspergualin is an intriguing, previously unknown observation and requires further investigation.

Effect of chromosome size on aberration levels caused by gamma radiation as detected by fluorescence in situ hybridization

Fluorescence in situ hybridization (FISH) is a powerful technique for detecting genomic alterations at the chromosome level. To study the effect of chromosome size on aberration formation, we used FISH to detect initial damage in individual prematurely condensed chromosomes (PCC) of gamma-irradiated G0 human cells. A linear dose response for breaks and a nonlinear dose response for exchanges was obtained using a chromosome 1-specific probe. FISH detected more chromosome 1 breaks than expected from DNA based extrapolation of Giemsa stained PCC preparations. The discrepancy in the number of breaks detected by the two techniques raised questions as to whether Giemsa staining and FISH differ in their sensitivities for detecting breaks, or is chromosome 1 uniquely sensitive to gamma-radiation. To address the question of technique sensitivity, we determined total chromosome damage by FISH using a total genomic painting probe; the results obtained from Giemsa-staining and FISH were nearly identical. To determine if chromosome 1 was uniquely sensitive, we selected four different sized chromosomes for paint probes and scored them for gamma-ray induced aberrations. In these studies the number of chromosome breaks per unit DNA increased linearly with an increase in the DNA content of the chromosomes. However, the number of exchanges per unit of DNA did not increase with an increase in chromosome size. This suggests that chromosome size may influence the levels of aberrations observed. Extrapolation from measurements of a single chromosome's damage to the whole genome requires that the relative DNA content of the measured chromosome be considered.

A phase-I clinical study of low-dose oral interferon-alpha

Twenty-five patients with systemic malignancies or cutaneous disorders were treated with low dosages (1-16 IU/kg/day) of oral interferon-alpha in a phase-I study. There were no grade-3 or -4 toxicities. No patients achieved a partial or complete response. One patient with renal cell carcinoma had prolonged disease stabilization lasting for 22 months. No significant changes in lymphocyte subsets including T4/T8 ratio, or serum immunoglobulins were observed. Subjective improvement in general well-being was reported by three patients. Low dosages of interferon-alpha administered orally do not appear to have any significant immunomodulatory or antitumor activity.

Phase II study of alpha-interferon and 13-cis-retinoic acid in metastatic melanoma

The combination of alpha-interferon and 13-cis-retinoic acid has shown significant activity against a number of human tumors. We conducted a phase II trial to test whether the combination would have a major response rate of 30% or more in patients with refractory, metastatic melanoma. Eleven patients were treated on the study. Alpha-interferon was administered subcutaneously three times a week at a dose of 10 million U/m2 and 13-cis-retinoic acid was administered orally at a dose of 1 mg/kg/day. No patient achieved a partial or complete remission. The combination of alpha-interferon and 13-cis-retinoic acid is unlikely to have significantly higher therapeutic activity than alpha-interferon alone.

Strategies for the application of biomarkers for risk assessment and efficacy in breast cancer chemoprevention trials

Current chemoprevention trial designs based on epidemiological risk assessment and occurrence of cancer as an endpoint are inefficient and expensive. Novel biomarkers are needed to facilitate the development of chemopreventive interventions. The following four categories of biomarkers may be useful in prevention trials: histologic and morphometric markers; phenotypic markers of dysregulated proliferation, differentiation, and cell loss; specific oncogenes and growth regulators which are qualitatively or quantitatively altered in breast cancers; and markers of genetic and epigenetic instability. Some of these markers will be generally useful regardless of the chemopreventive approach used, whereas others may be uniquely useful in trials of specific chemopreventive agents [e.g., upregulation of progesterone receptor (PR) expression in response to tamoxifen]. The development of these markers requires three phases of study: "Phase I": assessing the prevalence of the putative marker in malignant and premalignant tissue from individuals who have developed breast cancer; "Phase II": assessing in vivo modulation of the biomarker by the proposed chemopreventive agent; and "Phase III": applying the proposed biomarker in larger-scale trials of chemopreventive agent in high-risk populations, either before or after the development of a primary breast malignancy. The use of these biomarkers may also allow identification of novel targets for chemoprevention.

Chromosome in situ hybridization on formalin-fixed mammary tissue using non-isotopic, non-fluorescent probes: technical considerations and biological implications

Fluorescent in situ hybridization techniques have provided an important tool for interphase cytogenetic studies of human neoplasms. However, these techniques are difficult to use on formalin-fixed archival tissue sections. We describe here a non-fluorescent, non-isotopic in situ hybridization (ISH) approach that is easily applicable to paraffin-embedded breast tissue sections. The technical steps that must be monitored and individualized to optimize signal generation and detection are discussed. This ISH technique has several advantages over fluorescent detection methods. The signal obtained can be viewed using an ordinary light microscope and does not fade with time. More importantly, the signal is observed and analyzed in the context of tissue morphology. The technique permits detection of numerical chromosomal abnormalities not only in malignant but also in apparently normal and potentially premalignant mammary tissue. This may allow identification of focal genetic abnormalities as well as field-defects and enable analysis of their evolution during the multistep transformation to mammary neoplasm. This technique is also suitable for analysis of tumor heterogeneity and the correlation of numerical chromosomal aberrations with histologic, immunocytochemical, and clinical features of breast tumors.