Juan C. Felix

p53 Mutations and expression in ovarian cancers : Correlation with overall survival

The p53 gene is altered in approximately 50% of all human malignancies. p53 overexpression, identified by immunohistochemistry, and p53 mutations, identified by single-strand conformational polymorphism (SSCP) and DNA sequencing, have been described in ovarian cancers. p53 overexpression has been correlated with poor outcome for women with ovarian cancer in some studies. With only limited data, the assumption has been made that p53 overexpression corresponds to p53 mutations. The purpose of this investigation was to assess p53 alterations in ovarian cancer to determine if p53 overexpression corresponds with mutations in the p53 gene, and to assess whether either predicts clinical outcome in ovarian carcinoma. Frozen ovarian carcinoma tumor specimens from 105 patients were analyzed by immunohistochemical staining for p53 expression. SSCP was used to screen for mutations and DNA sequencing was used to confirm the specific mutation in exons 2 to 11, encompassing the entire p53 open reading frame. Those ovarian carcinomas identified as wild-type p53 by SSCP were subjected to automated DNA sequence analysis of the entire open reading frame. Relative to DNA sequence analysis, the sensitivity of SSCP was 85% and the specificity was 98%. Immunohistochemical staining demonstrated that 72 of the 105 (69%) cases had positive immunostaining. SSCP and DNA sequencing identified and confirmed mutations in 60 of the 105 carcinomas (57%). Although there was a statistically significant association between p53 immunostaining and p53 mutations (p = 0.0002), false-negative and -positive results were identified. Tumor grade (p = 0.03), stage (p = 0.08), and overall survival (p = 0.15) were moderately associated with positive p53 immunostaining. Patients with p53 mutations and overexpression had shorter overall patient survival (p = 0.02). The findings demonstrated that, individually, p53 mutations and p53 overexpression were each related to shorter patient survival, but the strongest predictor of outcome was a combination of both mutations and overexpression. Comparisons of overall survival for women with mutations in loop 2, loop 3, and the loop-sheet-helix domains together showed a statistically significant difference in survival compared to survival of women whose ovarian cancers had other mutations (p = 0.046).

Cold-knife conization versus conization by the loop electrosurgical excision procedure: A randomized, prospective study

Abstract Objective: Our purpose was to compare the diagnostic ability and treatment efficacy of conization by the loop electrosurgical excision procedure with cold-knife conization. Study Design: One hundred eighty women who required conization for diagnosis and treatment of cervical dysplasia or microinvasive cervical carcinoma were prospectively enrolled in a randomized clinical trial to receive either cold-knife conization or conization by the loop electrosurgical excision procedure. Conization complications, rate of lesion clearance, and therapeutic outcome were assessed for the 2 study groups. Results: There were no statistically significant differences in the complication rate ( P = 1.00), the rate of lesion clearance ( P = .18), or the rate of disease recurrence ( P = .13) between the 2 study groups. The mean follow-up was 11.2 months in the cold-knife conization group and 10.4 months in the loop-excision conization group. Conclusion: Cold-knife conization and loop-excision conization yield similar diagnostic and therapeutic results. (Am J Obstet Gynecol 1999;180:276-82.)

p53 Immunostaining as a Significant Adjunct Diagnostic Method for Uterine Surface Carcinoma: Precursor of Uterine Papillary Serous Carcinoma

Uterine papillary serous carcinoma (UPSC) is a biologically aggressive carcinoma that causes a disproportionate number of endometrial cancer deaths because of its dismal clinical outcome. Although the precursor lesion of UPSC has been suggested both morphologically and molecularly, diagnosis continues to represent a challenge to surgical pathologists, particularly in biopsy specimens, largely in part because of its multiple histologic patterns and many benign morphologic mimics. In this study, we used p53 immunohistochemical staining as an adjunct test to correctly identify six cases of uterine surface carcinoma (USC) prospectively and three cases retrospectively. Both sensitivity and specificity for this immunostaining method approached 100% when the cutoff score of p53 overexpression was 7 or higher. The precision estimated by receiving operating characteristic curve was 100%, indicating that the diagnostic value of the score for p53 overexpression was very high. p53 immunohistochemical staining was considered a significant adjunct diagnostic method for the probable precursor lesion of UPSC. The probable precursor lesion of UPSC, previously referred to as endometrial intraepithelial carcinoma or endometrial carcinoma in situ, appears to represent the early phase of UPSC. However, unlike its names would suggest, this lesion is often multicentric and behaves in a more aggressive fashion than regular in situ carcinomas. For this reason, we prefer the term uterine surface carcinoma, a term that is more descriptive and less restrictive, to emphasize the unique aggressive nature of the UPSC precursor lesion. The reason we postulate using the term uterine surface carcinoma rather than endometrial intraepithelial carcinoma or endometrial carcinoma in situ is that the latter terms would seem define a neoplastic process confined to the endometrial epithelium without potential for metastasis. In reality, the precursor lesion of UPSC has a tendency to stromal and vascular space involvement as seen by the presence of stromal and vascular invasion in one of the prospectively identified USC cases. Therefore, the term uterine surface carcinoma is selected to alert clinicians that this early carcinoma has features of carcinoma in situ, but still carries a potential for metastasis.

Alterations in DNA methylation are early, but not initial, events in ovarian tumorigenesis.

We compared global levels of DNA methylation as well as methylation of a specific locus (MyoD1) in ovarian cystadenomas, ovarian tumours of low malignant potential (LMP) and ovarian carcinomas to investigate the association between changes in DNA methylation and ovarian tumour development. As we realized that cystadenomas showed different methylation patterns from both LMP tumours and carcinomas, we verified their monoclonal origin as a means of confirming their true neoplastic nature. High-pressure liquid chromatographic (HPLC) analyses showed that global methylation levels in LMP tumours and carcinomas were 21% and 25% lower than in cystadenomas respectively (P = 0.0001 by one-way variance analysis). Changes in the methylation status of the MyoD1 locus were not seen in any of ten cystadenomas analysed but were present in five of ten LMP tumours and in five of ten carcinomas (P = 0.03). These findings suggest that alterations in DNA methylation are absent (or at least not as extensive) in ovarian cystadenomas, but are present in LMP tumours, the phenotypic features of which are intermediate between those of benign and malignant ovarian tumours. The results also emphasize the merit of distinguishing ovarian LMP tumours from cystadenomas, in spite of their similar clinical characteristics.

The proto-oncogene c-kit is expressed in leiomyosarcomas of the uterus.

OBJECTIVE The proto-oncogene c-kit encodes for a 145-kDa transmembrane tyrosine kinase receptor. Interaction with its ligand, stem cell factor, is essential in the development of hematopoietic stem cells, mast cells, gametocytes, melanocytes, and interstitial cells of Cajal. C-kit expression has been identified in a number of different neoplasms that includes mastocytosis/mast cell leukemia, acute myeloblastic leukemia, seminoma/dysgerminoma, and gastrointestinal stromal tumors. This study examines c-kit expression in uterine endometrial stromal sarcomas, leiomyomas, and leiomyosarcomas using immunohistochemistry. METHODS Archival tissue from 38 patients with the uterine mesenchymal tumors (16 leiomyosarcomas, 8 leiomyomas, 11 low-grade endometrial stromal sarcomas, and 3 high-grade endometrial stromal sarcomas) was stained with polyclonal antibody for c-kit. Modified avidin biotin (ABC) immunoperoxidase method was employed for antibody detection. Individual tumors were considered positive if more than 10% of the cells comprising the neoplasm displayed immunoreactive staining. Staining intensity was graded 1+ to 3+ and distribution graded as focal (10-30% of the cells), intermediate (30-60% of the cells), or diffuse (>60% of the cells). RESULTS C-kit was positive in 12 (75%) of the 16 leiomyosarcomas. The staining was 3+ and diffuse in the majority of the positive tumors. C-kit expression was not detected in any of the 8 leiomyomas. Two of the 3 high-grade endometrial stromal sarcomas displayed c-kit positivity. Staining was diffuse and 3+ in both of these tumors. Expression of c-kit was observed in only 3 of the 11 low-grade endometrial stromal sarcomas. CONCLUSIONS C-kit is expressed in uterine leiomyosarcomas and endometrial stromal sarcomas. Adjunctive diagnostic studies using c-kit may be useful in distinguishing leiomyosarcomas from benign leiomyomas in uterine tumors that offer uncharacteristic features. Furthermore, studies should investigate the prospect of treating these malignant tumors with tyrosine kinase inhibitors.

Identification of micrometastases in histologically negative lymph nodes of early-stage cervical cancer patients.

OBJECTIVE: Despite histologically negative lymph nodes, approximately 15% of patients with early-stage cervical cancer will develop recurrence. Micrometastases have been shown to be important in staging and treatment of breast cancers and melanoma and have been identified by polymerase chain reaction analysis in cervical cancers. This study sought to estimate the frequency of micrometastases identified by immunohistochemistry in histologically negative lymph nodes and compare this to other known risk factors for recurrence of cervical cancer. METHODS: Early-stage (stages IA2, IB1, and IB2) cervical cancer patients of all histologic subtypes were identified from the surgical logs of the Los Angeles County–University of Southern California Medical Center for the period 1994–2000. One hundred thirty-two patients had histologically negative lymph nodes. Immunohistochemical assay was performed on 3,106 lymph nodes by using antibodies against cytokeratins AE-1 and CAM 5.2 in combination according to standard protocols. The stained nodes were then evaluated for the presence of micrometastases and compared against the respective clinicopathologic information in each case. RESULTS: Micrometastases were detected in 19 of 132 (15%, 95% confidence interval [CI] 9%, 22%) patients, found in 29 of the 3,106 (0.9%) lymph nodes evaluated. Vascular space invasion was seen in 50 of 132 cases (38%, 95% CI 30%, 47%) and in 8 of 19 (42%, 95% CI 21%, 66%) cases with micrometastases. Surgical margins of the resected specimen were negative in 120 of 132 cases (91%, 95% CI 84%, 95%) and in 16 of 19 (84%, 95%CI 60%, 96%) of those cases with micrometastases. Micrometastases were seen most frequently in pelvic lymph nodes (25 of 29, 86%). Patients with more than 20 lymph nodes removed were more likely to demonstrate metastasis (P < .001). There was no statistically significant association between micrometastasis and vascular space invasion or tumor volume. CONCLUSION: Micrometastases are identifiable in histologically negative lymph nodes in 15% (95% CI 9%, 22%) of early-stage cancer patients, a frequency which approximates the recurrence rate for patients with negative nodes. In this series, patients with greater numbers of lymph nodes analyzed were more likely to have lymph node micrometastasis identified. There appears to be no relationship between tumor volume and the identification of micrometastases. Although micrometastases can be identified in histologically negative lymph nodes, their presence is not strongly associated with other known factors of cervical cancer recurrence. Further research is needed to determine whether the presence of lymph node micrometastases is associated with an unfavorable prognosis. LEVEL OF EVIDENCE: II-3

Triage of atypical squamous cells of undetermined significance with hybrid capture II: colposcopy and histologic human papillomavirus correlation.

OBJECTIVE To estimate the effectiveness of Hybrid Capture II to predict high-grade cervical intraepithelial neoplasia (CIN) from a cytological cervical sample. Evidence of high-risk human papillomavirus (HPV) was also determined from biopsy samples using the polymerase chain reaction (PCR) for women referred with atypical squamous cells of undetermined significance (ASCUS) Papanicolaou smears. METHODS: We screened 8170 women with Papanicolaou smears, of whom 278 (3.4%) returned ASCUS. All ASCUS cases underwent colposcopy and Hybrid Capture II testing. High-grade CIN biopsy specimens were tested for high-risk HPV by PCR. RESULTS Nearly 30% of ASCUS cases had CIN biopsy results (11.9% showing CIN II or CIN III and 17.6% showing CIN I). Hybrid Capture II positive rates were 93.3% for cases with CIN III, 72.2% for CIN II, and 51.0% for CIN I (P< .001). ASCUS-Premalignant Process Favored cases showed a 28.1% high-grade biopsy rate and a 100% Hybrid Capture II positive rate. For ASCUS-Undefined and ASCUS-Reactive Process Favored cases, Hybrid Capture II returned positive in 90.9% of CIN III and 61.5% of CIN II cases (P < .001). Sixty-nine of 178 (38.8%) patients with no evidence of CIN tested positive for Hybrid Capture II. Human papillomavirus deoxyribonucleic acid (DNA) high-risk subtypes were detected by PCR in the tissue of all high-grade CIN cases with negative Hybrid Capture II results. CONCLUSION Hybrid Capture II returned negative in 25% of cases with biopsy-proven high-grade CIN with associated high-risk HPV DNA by PCR (non-Premalignant ASCUS subset), and positive in 39.3% of cases with normal results; this limits its clinical utility.

Norethindrone acetate and estradiol-induced endometrial hyperplasia☆

Objective To identify the lowest effective continuous dose of norethindrone acetate that significantly reduces 12-month incidence of endometrial hyperplasia associated with unopposed 17β-estradiol (E2), 1 mg. Methods In a double-masked, randomized, multicenter study, 1176 healthy postmenopausal women 45 years of age or older without evidence of endometrial abnormalities were given 12 months of treatment with unopposed E2, 1 mg, or continuous-combined regimens of E2, 1 mg, and norethindrone acetate, 0.1 mg, 0.25 mg, or 0.5 mg. Endometrial histology was evaluated at the end of the treatment period. Results Continuous-combined E2-norethindrone acetate regimens significantly reduced 12-month incidence of endometrial hyperplasia compared with unopposed E2 1 mg (P < .001). Endometrial hyperplasia occurred in 14.6% of women treated with unopposed E2 1 mg, whereas in all continuous-combined groups, the rate decreased to less than 1%. Among patients who received E2-norethindrone acetate 0.1 mg, incidence was 0.8%; among those who received 0.25 mg and 0.5 mg, it was 0.4%. Conclusion Continuous norethindrone acetate at doses as low as 0.1 mg combined with E2 1 mg effectively negated risk for endometrial hyperplasia associated with unopposed E2 1 mg, at least for the first year of therapy.

Development of angiotensin (1-7) as an agent to accelerate dermal repair

Angiotensin II has been shown to be a potent agent in the acceleration of wound repair. Angiotensin (1‐7), a fragment of angiotensin II that is not hypertensive, was found to be comparable to angiotensin II in accelerating dermal healing. This activity was evaluated in four models: rat and diabetic mouse full‐thickness excisional wounds; rat random flap; and guinea pig partial thickness thermal injury. In all models, angiotensin (1‐7) was comparable to angiotensin II. Angiotensin (1‐7) accelerated the closure of wounds in diabetic mice and rats. In diabetic mice the resultant tissue at day 25 after injury was more comparable to normal tissue than the fibrotic scar observed in placebo‐treated wounds. In the random flap model, angiotensin (1‐7) was comparable to angiotensin II in maintaining flap viability (approximately 82%) and flap survival (40%). Finally, angiotensin (1‐7) increased proliferation in the hair follicles at the edge of the wound and site of thermal injury, and the number of patent blood vessels on day 7 after partial thickness thermal injury. These data may be partially explained by the effect of angiotensin II and angiotensin (1‐7) on keratinocyte proliferation. While platelet‐derived growth factor had no effect on keratinocyte proliferation, angiotensin II and angiotensin (1‐7) significantly increased keratinocyte proliferation. These data show that angiotensin(1‐7) is comparable to angiotensin II in accelerating skin repair. Furthermore, the hypertensive and wound healing effects can be separated within the family of angiotensin peptides.

The role of endocervical curettage at cervical conization for high-grade dysplasia

Objective To quantify the risk of invasive cancer above the location where the conization specimen was taken in patients with an endocervical curettage (ECC) positive for dysplasia at conization for high-grade cervical intraepithelial neoplasia (CIN), and to determine if any pathologic features may influence this risk. Methods The charts of 104 patients who underwent cervical conization for high-grade dysplasia followed by repeat conization or hysterectomy at Los Angeles County + University of Southern California Womens Hospital between January 1986 and December 1992 were reviewed retrospectively. Patients with invasive cancer or glandular dysplasia on the initial conization were excluded. The ECC performed immediately after conization biopsy (conization ECC) was benign in 63 patients and contained dysplasia in 41. All available conization ECC specimens that contained dysplasia were evaluated for volume of dysplasia and degree of cytologic atypia. Fisher exact test was used for statistical comparison between and within groups. Results Invasive cancer was not present in any patients in the benign ECC group but was present in nine (22%) patients in the dysplasia group (P < .0001); five of these patients had microinvasion (no more than 3 mm of stromal invasion and no lymph-vascular space involvement) and four had frank invasion. Comparison of patients with involved endocervical margins revealed that none of 37 patients in the benign ECC group versus eight of 27 patients in the dysplasia group had invasive cancer (P < .0005) All patients with invasion were 35 years or older and all patients with frank invasion were 50 years or older. Neither volume nor cytologic grade of dysplasia in the ECC was predictive of invasion in the residual cervix. Conclusions An ECC at conization positive for dysplasia is an important predictor of invasion in the residual cervix of patients whose conization reveals high-grade intraepithelial neoplasia and should be routinely performed. Women 50 years or older with both a positive endocervical margin and conization ECC should undergo repeat conization before further therapy. Women under 50 years of age should undergo repeat conization if fertility is not desired; otherwise, close follow-up is necessary to exclude the presence of an invasive lesion in the residual cervix.