Molar pregnancy with a coexistent fetus after intracytoplasmic sperm injection. A case report.

BACKGROUND: Normal fertilization is usually considered to have occurred when two pronculei (2PN) and two polar bodies are observed. Exceptions are the single pronucleated zygote resulting from asynchronous pronuclei. CASE: A 29-year-old woman entered a program of intracytoplasmic sperm injection and embryo transfer because of her husband's oligoasthenoteratozoospermia. Two cleavage-stage embryos (four blastomeres, grade 1 and 2) were obtained from one fertilized oocyte containing distinct 2PN and the other a single pronucleus (1PN). At 15 weeks' gestation the patient developed severe preeclampsia requiring termination of the pregnancy. Histopathologic examination and DNA ploidy by image analysis were consistent with a twin pregnancy combining a complete hydatidiform mole and normal pregnancy. CONCLUSION: We hypothesize that this 1PN was at the origin of the hydatidiform mole. This case highlights the danger of transferring an embryo having 1PN.

Evolution of DNA ploidy during squamous cell carcinogenesis in the esophagus.

Image and flow cytometry was used to study the nuclear DNA content (ploidy) during the squamous cell carcinogenesis in the esophagus. The present retrospective study comprised 26 surgical specimens of squamous cell carcinomas (SCC) in patients who underwent surgery alone at the Department of Surgery in CHUV Hospital in Lausanne, between January 1992 and December 1999. We analyzed 53 healthy tissues, 43 tumors, and six lymph node metastases. Diploid DNA histogram patterns were observed in all non-pathologic tissues analyzed, either distant or proximal to the lesion. Aneuploidy was observed in 30 (70%) of 43 lesions; 20 (62.5%) of 32 early squamous-cell carcinomas; and 10 (91%) of 11 advanced carcinomas. In patients with various tumor stages or with multicentric synchronous or metachronous tumors, DNA content was not different among different tumor stages. Four of six lymph node metastases had the same DNA content as the primary tumor. In four patients, discordance between image and flow cytometry analysis was observed for malignant lesions only. Ploidy status was not statistically associated with the differentiation of the tumor, but it was associated with the stage of tumor (P < 0.001). These findings suggest that early malignant changes in the esophagus are already associated with alteration in DNA content, and aneuploidy tends to correlate with progression to invasive SCC. This cell kinetic information could help clinicians in selecting the optimal treatment for the individual patient.

Pharmacokinetics and pharmacodynamics of tetra(m-hydroxyphenyl)chlorin in the hamster cheek pouch tumor model: comparison with clinical measurements.

The pharmacokinetics (PK) of the photosensitizer tetra(m-hydroxyphenyl)chlorin (mTHPC) was measured by optical fiber-based light-induced fluorescence spectroscopy (LIFS) in the normal and tumoral cheek pouch mucosa of 29 Golden Syrian hamsters with chemically induced squamous cell carcinoma. Similar measurements were carried out on the normal oral cavity mucosa of five patients up to 30 days after injection. The drug doses were between 0.15 and 0.3 mg per kg of body weight (mg/kg), and the mTHPC fluorescence in the tissue was excited at 420 nm. The PK in both human and hamster exhibited similar behavior although the PK in the hamster mucosa was slightly delayed in comparison with that of its human counterpart. The mTHPC fluorescence signal of the hamster mucosa was smaller than that of the human mucosa by a factor of about 3 for the same injected drug dose. A linear correlation was found between the fluorescence signal and the mTHPC dose in the range from 0.075 to 0.5 mg/kg at times between 8 and 96 h after injection. No significant selectivity in mTHPC fluorescence between the tumoral and normal mucosa of the hamsters was found at any of the applied conditions. The sensitivity of the normal and tumoral hamster cheek pouch mucosa to mTHPC photodynamic therapy as a function of the light dose was determined by light irradiation at 650 nm and 150 mW/cm2, 4 days after the injection of a drug dose of 0.15 mg/kg. These results were compared with irradiations of the normal oral and normal and tumoral bronchial mucosa of 37 patients under the same conditions. The reaction to PDT of both types of human mucosae was considerably stronger than that of the hamster cheek pouch mucosa. The sensitivity to PDT became comparable between hamster and human mucosa when the drug dose for the hamster was increased to 0.5 mg/kg. A significant therapeutic selectivity between the normal and neoplastic hamster cheek pouch was observed. Less selectivity was found following irradiations of normal mucosa and early carcinomas in the human bronchi. The pharmacodynamic behavior of mTHPC was determined by test irradiations of the normal mucosa of hamsters and patients between 6 h and 8 days after injection of 0.5 and 0.15 mg/kg in the hamsters and the patients, respectively. The normal hamster cheek pouch showed a maximum response to irradiation 6 h after injection and then decreased continuously to no observable reaction at 8 days after injection. The reaction of the normal human oral mucosa, however, showed an increasing sensitivity to the applied light between 6 h and 4 days after mTHPC injection and then decreased again at 8 days. The hamster model with the chemically induced early squamous cell cancer in the cheek pouch thus showed some similarity to the early squamous cell cancer of the human oral mucosa considering the PK. However, a quantitative difference in fluorescence signal for identical mTHPC doses as well as a significant difference in pharmacodynamic behavior were also observed. The suitability of this animal model for the optimization of PDT parameters in the clinic is therefore limited. Hence great care must be taken in screening new dyes for PDT of early squamous cell cancer of the upper aerodigestive tract based upon observables in the hamster cheek pouch model.

Wavelength-dependent effect of tetra(m-hydroxyphenyl)chlorin for photodynamic therapy in an 'early' squamous cell carcinoma model.

The purpose of the present study was to correlate the wavelength of the irradiation source with the phototoxic activity of tetra(m-hydroxyphenyl)chlorin (mTHPC) in healthy and neoplastic mucosae. The hamster tumour model for early squamous cell carcinoma was used in these experiments. In vitro and in vivo studies have shown that mTHPC absorbs significantly at 652 nm (1, 2). This wavelength is used currently in clinical mTHPC photodynamic therapy (PDT) trials. In order to study the wavelength dependence of the phototoxic effect on normal and tumour tissues, irradiation tests were performed 4 days after injection of 0.5mg kg(-1) mTHPC. An argon-ion pumped dye laser was used as the light source. The light dose of 12 J cm(-2) was delivered at a light dose rate of 150 mW cm(-2). The wavelength was varied between 642.5 and 665 nm at 2.5-nm increments. The PDT damage was evaluated in serial Haematoxylin and Eosin stained sections using a tissue-damage scale. Light between 647.5 and 652.5 nm induced the highest damage to both the healthy and tumour mucosae. At wavelengths equal to or below 645 nm, and equal to or above 655 nm, tissue damage decreased. Wavelengths below 642 nm and above 660 nm did not induce any visible tissue damage. These results suggest that the in vivo optimal wavelength range for PDT with mTHPC is between 647 and 652 nm. This information is essential for selecting an appropriate light source.

In vivo fluence rate effect in photodynamic therapy of early cancers with tetra(m-hydroxyphenyl)chlorin.

Several parameters affect clinical trials in photodynamic therapy and influence the therapeutic outcome. Beside drug dose, light dose, drug-light interval and other variables, the fluence rate is a parameter that can influence the therapeutic results. In this study we have evaluated the fluence rate effect with a second-generation photosensitizer, tetra(m-hydroxyphenyl)chlorin (mTHPC) using a 7,12-dimethylbenz(a)anthracene induced early squamous cell carcinoma of the Syrian hamster cheek pouch as a tumor model. Following injection of 0.5 mg/kg of mTHPC, irradiation tests were performed at two drug-light intervals, 4 and 8 days. Wavelength and light dose were adapted from those applied routinely in clinical trials. Irradiations at 652 nm were carried out with fluences ranging from 8 to 20 J/cm2 delivered at fluence rates of 15 and 150 mW/cm2. Similar tests were also performed at 514 nm with a fluence of 80 J/cm2 delivered at fluence rates ranging from 25 to 125 mW/cm2. At both wavelengths and drug-light intervals for a given fluence, the higher fluence rates resulted in less tissue damage in tumor and healthy mucosae. However, the lower fluence rates yielded slightly less therapeutic selectivity. This study confirms that the fluence rate is of major importance in clinical PDT.