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PubMed1993

High-dose cisplatin and cyclophosphamide with glutathione in the treatment of advanced ovarian cancer.

BACKGROUND: On the basis of preliminary results achieved with a high-dose cisplatin regimen including glutathione as chemoprotector, the efficacy and toxicity of the new regimen was further evaluated in a larger series of patients with advanced ovarian cancer (stage III and IV). PATIENTS AND METHODS: The study included patients with bulky or extensive residual disease after primary laparotomy or with bulky inoperable tumor masses. A total of 79 patients were treated with up to five courses of high-dose cisplatin (40 mg/m2 daily in normal saline, for four days) plus glutathione (2500 mg as a short-term infusion before cisplatin), together with cyclophosphamide (600 mg/m2 as an i.v. bolus on day 4). A standard i.v. hydration consisting of a total of 2000 ml of fluids without diuretics was employed. RESULTS: All eligible patients, who received a total of 345 courses, were assessed for response and toxicity and 52 received the planned five courses of the protocol. Forty-five patients (57%) achieved complete clinical responses and 20 (25%) had partial remissions for an overall response rate of 82%. The response rate was critically dependent on tumor size before chemotherapy. Thirty-eight of 45 patients who had complete clinical responses underwent second-look laparotomy, and 29 had pathological complete responses (37%). Seventeen of these 29 patients subsequently relapsed (median disease-free interval, 12 months; range, 6-45). With a median follow-up time of 44 months, the median survival for the 79 analyzed cases was 40 months. The toxicity of the regimen was moderate. Nausea/vomiting was the most severe acute toxicity. Myelotoxicity was acceptable, with severe leukopenia and thrombocytopenia (grade 4) occurring in 8% and 3% of patients, respectively. Nephrotoxicity was minimal with a transient increase (to < 2 mg/dL) in serum creatinine in only 6 patients (8%). Peripheral neurotoxicity and ototoxicity were the most significant long-term toxicities. The severity of these side effects (grade 3 WHO neurotoxicity occurred in only 4% of patients) was apparently less than has been reported with other high-dose cisplatin regimens. Neurotoxicity required discontinuation of therapy in three patients after four courses. Most affected patients had complete or partial recovery of symptoms with time. DISCUSSION: The efficacy and tolerability of the regimen confirm the feasibility of this new approach including glutathione in order to increase cisplatin dose intensity. The superiority of this regimen over standard induction therapy should be confirmed in randomized trials.

Adult↗

PubMed1985

Antitumoral activity of human fibroblast interferon administered intranodularly.

Human fibroblast interferon was given intranodularly to 14 patients with cutaneous metastases from breast cancer and malignant melanoma; 1,000,000 units/cm3 of tumor tissue was administered daily for 8-10 days. 13 patients were evaluated. Complete response was achieved in 1 of 7 breast carcinoma nodules and in 2 of 6 melanoma nodules; partial response was achieved in 1 of 7 breast carcinoma and in 3 of 6 melanoma nodules. The overall objective response was therefore 7 of 13 (53.8%) metastatic nodules. Pathological complete response was confirmed in 2 of 3 complete clinical responses. Necrosis, lymphocytic infiltration and fibrosis were observed in all the specimens pathologically examined. In spite of a clear antitumoral activity, this approach does not appear to have clinical significance due to its extremely localized effect.

Adult↗

PubMed2004

Biweekly docetaxel and gemcitabine as neoadjuvant chemotherapy in stage II and III breast cancer patients: preliminary results of a phase II and pharmacogenomic study.

The purpose of this study is to evaluate the efficacy and safety of a biweekly neoadjuvant docetaxel/gemcitabine regimen in patients with histologically confirmed stage II and III breast cancer. In addition, a cDNA microarray study attempted to correlate pretreatment gene-expression profile with clinical and pathologic responses. Docetaxel 65 mg/m(2) was given in a 60-minute intravenous infusion followed by gemcitabine 2,500 mg/m(2) in a 30-minute intravenous infusion every 2 weeks for six cycles; prophylaxis with growth factors was allowed. Four cycles of standard AC (doxorubicin 60 mg/m(2) and cyclophosphamide 600 mg/m(2)every 21 days) was routinely delivered to all patients postsurgery. Thirty patients are accrued on-study so far. The overall response rate for 24 evaluable patients was 79% (95% confidence interval, 9.7 to 53.5) with six complete responses and 13 partial responses. One patient (4%) out of 23 achieved a pathologic complete response in the breast at the time of definitive surgery. Breast conservation procedure was possible in 14 patients (61%). A total of 161 cycles has been delivered. Grade 1/2 alopecia and a mild grade 1/2 LDH increase were the most frequently reported adverse events (78% and 55% of cycles, respectively). Grade 3/4 neutropenia was reported in 18 cycles (11%). These preliminary results show that biweekly docetaxel and gemcitabine is an optimal regimen as neoadjuvant treatment of stage II and III breast cancer. In spite of the large tumor size, breast conservation was possible in 61% of the patients. In general, toxicity was very manageable.

Adult↗

PubMed2005

Resection of residual disease in patients with metastatic gastrointestinal stromal tumors responding to treatment with imatinib.

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal tumors of the gastrointestinal tract. Long-term survival of patients with metastatic disease has only been observed in patients with completely resected disease. Recently, the tyrosine kinase inhibitor imatinib has been found to yield responses in the majority of patients with metastatic GIST suggesting improved resectability in responding patients. Combined treatment approaches including resective surgery after imatinib treatment in patients with advanced metastatic disease have rarely been explored. We report a series of 90 patients with metastatic GIST in whom treatment with imatinib enabled 12 patients with mostly recurrent and extensive disease to be considered for resection of residual disease. In 11 of these patients, complete resection could be achieved. Viable tumor cells were found in all but one resected specimens suggesting that despite favorable radiological or clinical responses, imatinib is unlikely to induce pathological complete responses. Until more mature data from prospective trials are available, these data suggest that an early aggressive surgical approach should be considered for all patients with metastatic GIST. Further trials investigating a combined surgical and pre/postoperative treatment with imatinib in patients with advanced metastatic GIST are warranted.

Adult↗

PubMedDate not supplied

Anastrozole as neoadjuvant therapy for patients with hormone-dependent, locally-advanced breast cancer.

BACKGROUND: We investigated the efficacy and safety of anastrozole as neoadjuvant therapy in a group of postmenopausal patients with locally-advanced breast cancer. PATIENTS AND METHODS: This was an open-label trial, which recruited patients with histopathologically-confirmed unilateral, locally-advanced, estrogen-receptor-positive breast cancer (stage IIIA/B). All patients received anastrozole 1 mg/day for 3 months, after which the clinical response was evaluated. All patients with a complete or partial clinical response (cCR or cPR) underwent surgery (radical modified mastectomy), after which patients continued with the same therapy for two years or until progression. Primary end points were clinical response rate (cCR + cPR), surgery rate, pathological complete response rate and tolerability profile. RESULTS: cCR and cPR were seen in 61/112 (54.5%) and 32/112 (28.6%) patients (n=112), respectively, giving an objective response rate of 93/112 (83%) patients. Following surgery in responding patients, 14/61 patients (23%) had a pathological CR and 47/61 (77%) patients had a pathological PR. CONCLUSION: Neoadjuvant anastrozole treatment was highly effective and well-tolerated in postmenopausal women with hormone-dependent locally-advanced breast cancer.

Aged↗

PubMed2006

A phase II study of neoadjuvant docetaxel plus doxorubicin (KBCS-01) in stage II, III breast cancer.

BACKGROUND: This multicenter phase II study was conducted to evaluate the response and safety of a combination of docetaxel plus doxorubicin as neoadjuvant therapy for stage II, III breast cancer. METHODS: Patients with stage II or III breast cancer underwent three cycles of neoadjuvant chemotherapy with doxorubicin 50 mg/m2 and docetaxel 75 mg/m2 every 3 weeks followed by curative surgery. Prophylactic GCSF was not used. RESULTS: Ninety patients were enrolled in the study and 86 were evaluable for efficacy. The median age was 43 years (range, 30-69). The mean relative dose intensity was 0.98 for docetaxel and 0.98 for doxorubicin. Breast-conserving surgery was performed in 12 (13.7%) patients. The clinical overall response rate was 86% and pathologic complete response was 10.5%. Grade 3/4 neutropenia was observed in 26% of total 258 cycles and febrile neutropenia was observed in 15.8%. Pneumonia was observed in one patient and grade 3 mucositis was observed in three patients. CONCLUSION: Docetaxel and doxorubicin was an effective and well-tolerated neoadjuvant chemotherapy for stage II and III breast cancer. Clinical benefit of this treatment will be confirmed by survival data with long term follow up.

Adult↗

PubMed1993

Cisplatin, methotrexate and vinblastine plus surgical restaging for patients with advanced transitional cell carcinoma of the urothelium.

Chemotherapy with cisplatin, methotrexate and vinblastine (CMV) is active in advanced transitional cell carcinoma of the urothelium. Aggressive surgical resection of residual disease following responses produced by CMV was incorporated into a combined modality approach. Between 1982 and 1990, 64 patients were entered into the study. Of 55 patients evaluable for response 11 (20%) had a pathological complete response, 14 (25%) achieved a complete response following resection of residual disease and 5 (9%) whose disease was not surgically restaged had a clinical complete response. The overall complete response rate was 55%. Patients with liver, lung or bone involvement had significantly decreased survival compared to patients without visceral disease (p = 0.002). With a median followup exceeding 50 months, 14 patients (22% of all patients entered into the study) were free of disease at 23 to 98+ months. There were no deaths related to treatment. CMV produced high rates of response in patients with advanced disease, including those with distant metastases. Surgical resection of residual disease following responses produced by chemotherapy proved to be feasible, without treatment related mortality, and may have prolonged survival in selected cases.

Adult↗

PubMed1993

Neoadjuvant cisplatin, methotrexate and vinblastine for muscle-invasive bladder cancer: long-term followup.

A total of 26 patients with locally advanced bladder cancer received chemotherapy consisting of cisplatin, methotrexate and vinblastine. Radical cystectomy was performed in 24 of 26 patients (92%) receiving neoadjuvant therapy, with a pathological complete response in 6 (23%) and pathological partial response in 1 (4%) for an overall response rate of 35% (95% confidence limits 17 to 56%). The overall median survival time is currently undefined. Of the patients 15 (58%) are alive with a median followup of 48.6 months. Response rates from this neoadjuvant chemotherapy appear to be similar to those reported with methotrexate, vinblastine, doxorubicin and cisplatin, and may represent a therapeutically equivalent regimen but neither may be curative in the majority of the patients.

Adult↗

PubMed1996

Hyperthermic isolated limb perfusion with cisplatin in four patients with sarcomas of soft tissue and bone.

The value of hyperthermic isolated limb perfusion (HILP) with cisplatin in the management of locally advanced soft tissue sarcomas or metastatic bone sarcoma was studied. Four patients were treated with HILP under mild hyperthermia (39-40 degrees C) with 20-30 mg cisplatin/l perfused limb volume. Toxicity in the perfused limbs was moderate, and the erythema and oedema that occurred resolved spontaneously within 7-14 days as did the slight motor and sensory neuropathy over a longer period of time. Clinically, a reduction of pain was observed in all patients. Two weeks after perfusion, tumour biopsies were taken to evaluate tumour response. Two patients showed a pathological complete response, one patient showed >90% necrosis and one patient showed no response. Currently patients are treated with tumour necrosis factor and melphalan as perfusion agents. The above-mentioned results make the combination of tumour necrosis factor with cisplatin in the isolated limb perfusion setting an interesting option.

Adult↗

PubMed2004

'Quick course' neoadjuvant chemotherapy with cisplatin, bleomycin and vincristine in advanced cervical cancer.

To evaluate the response and safety of 'quick course' neoadjuvant chemotherapy, 30 patients with advanced squamous cell carcinoma of cervix were given cisplatin, bleomycin, and vincristine weekly for 3 courses. The response was evaluated by subjective parameters and by standard response criteria. In addition to the marked improvement in symptoms, the overall objective response was 60% with a complete pathological response of 6.6%. Tumor volume decreased significantly (p=0.002) after chemotherapy. Patients with stage IB and 27% (3 of 11) of patients with stage II disease who became technically stage IB (stage reduction) after chemotherapy underwent surgery. Radiotherapy was given to the remaining patients. All patients tolerated the chemotherapy.

Adult↗

PubMed2004

Neoadjuvant FEC 100 for operable breast cancer: eight-year experience at Centre Jean Perrin.

This study investigated the efficacy and tolerability of FEC 100 (epirubicin 100 mg/m2 with 5-fluorouracil 500 mg/m2 and cyclophosphamide 500 mg/m2) every 21 days as neoadjuvant chemotherapy in women with stage I-III primary operable breast cancer. Forty patients were treated with 6 cycles of FEC 100, followed by surgery and radiation therapy. In addition, most patients also received an adjuvant treatment for residual disease (11 chemotherapies and 31 tamoxifen). After 6 cycles of FEC 100, the overall clinical response rate of 75% (CI 95%, 61.6-88.4) was achieved, 22.5% of which were complete responses. Breast conservation was achieved in 70% of patients. A pathologic complete response was confirmed in 6 patients (15%; CI 95%, 3.9-26.1) using Chevallier's classification and in 10 patients (25%; CI 95%, 11.6-38.4) using Sataloff's classification. After a median follow-up of 29.5 months, 3 metastatic relapses were observed. The principal toxicity of FEC 100 was myelosuppression; 51.3% of patients developed grade 3/4 neutropenia. Neoadjuvant FEC 100 was both effective and well tolerated in patients with early-stage operable breast cancer.

Anemia↗

PubMedDate not supplied

Chemotherapy with vinorelbine, cisplatin and continuous infusion of 5-fluorouracil in locally advanced breast cancer: a promising low-toxic regimen.

Primary chemotherapy for locally advanced breast cancer, usually an anthracycline-containing regimen, improves local disease control allowing for an initially inoperable tumour to be resected. The feasibility and efficacy of a regimen containing vinorelbine (V), cisplatin (P) and 5-fluorouracil (5-Fu) as continuous infusion (ViFuP regimen) for patients with locally advanced breast cancer were evaluated. Twenty-six patients with a T4 breast cancer presentation (eight also had synchronous distant metastases) were treated with V (20 mg total dose i.v. on day 1 and day 3), P (60 mg/m2 i.v. on day 1) and 5-Fu (200 mg/m2/d as continuous infusion) all given every 3 weeks for a maximum of 6 courses. Eleven patients had an inflammatory breast lesion, 4 had a T4a and 11 a T4b presentation. Among those with metastases, 6 had one site and 2 had two sites of disease. After chemotherapy all tumors except one became operable. Objective response was observed in 19 out of the 26 evaluable patients (73%; 95% CI: 52-88%): fourteen had a partial response (54%); 5 had a clinically complete response (19%) and 5 had complete pathological response (20%; 95% CI: 7-41%). Seven patients had stable disease (27%) while no disease progression under treatment occurred. Mild or moderate side-effects included neutropenia (G1-G2 in 58% and G3 in 31% of patients), anemia (G1 in 19%), nausea and/or vomiting (G1-G2 in 92% of patients), mucositis (G1-G2 in 23%), diarrhea (G1 in 19%), plantar-palmar erythema (G1 in 12%) and alopecia G1 in 27% of patients. We conclude that the ViFuP regimen is well-tolerated and its use results in a high response rate. Thus ViFuP may be considered a relevant alternative to more toxic regimens, with an acceptable response rate. Despite the lack of a formal demonstration of equal efficacy with more toxic regimens commonly applied in locally advanced breast cancer, testing new modalities or drugs might provide a more fruitful strategy for relevant therapeutic progress.

Adult↗

PubMed2005

[Response rates following neoadjuvant chemotherapy and breast preserving treatment in patients with locally advanced breast cancer].

INTRODUCTION: The neoadjuvant chemotherapy is increasingly being used in the treatment of patients with locally advanced breast cancer. We describe the hypothesis of the biological behaviour of breast cancer supporting the reason for the existence of this treatment. The improvement of neoadjuvant chemotherapy is being discussed as well as the advantages, disadvantages and problems of the treatment. THE AIM OF EXAMINATION: To study the results of neoadjuvant chemotherapy in patients with locally advanced breast cancer and the proportion of breast preserving surgery after the treatment. METHODS: Sixty seven patients were given neoadjuvant chemotherapy treatment between 01.01.1999 and 12.31.2003. Twenty three patients were stage III A while 35 stage III B and 9 stage III C. 63% of the patients received CEF chemotherapy and 19% were given MMM. 18% were given neoadjuvant Taxotere + Carboplatin and 4% were given Taxotere + Farmorubicin chemotherapy. RESULTS: After neoadjuvant chemotherapy 5 patients had SD (stable disease), 32 patients had MR (minor response) and in 28 cases patients had PR (partial response). Two patients showed pCR (complete pathologic response). Twenty patients (30%) had breast preserving surgery. CONCLUSIONS: On the basis of our own experience neoadjuvant therapy is justified in patients with locally advanced breast cancer as they have bigger chance for breast preserving surgery. If mastectomy and axillary block dissection has to be carried out they are easier to perform. Taxans must be introduced for neoadjuvant treatment in order to improve our results. A longer follow-up is necessary before drawing final conclusions.

Adult↗

PubMed1985

Six-drug chemotherapy (hexamethylmelamine, doxorubicin, cisplatin, cyclophosphamide, methotrexate, and 5-FU; CHAMP-5) for ovarian carcinoma: alternating sequences of combination regimens.

Twenty-five patients with previously untreated adenocarcinoma of the ovary (International Federation of Gynecology and Obstetrics, stages II, III, and IV) were placed on a six-drug trial (CHAMP-5) for 18 months. This trial consisted of 28-day cycles of hexamethylmelamine, doxorubicin, and cisplatin alternating with hexamethylmelamine, cyclophosphamide, methotrexate, and 5-FU. After a minimum follow-up of 31 months, 14 (56%) of the 25 evaluable patients achieved complete or partial response and nine (36%) achieved complete pathologic response. Although CHAMP-5 is effective in the treatment of ovarian cancer, the results in these patients are not substantially different from those achieved with hexamethylmelamine, doxorubicin, and cisplatin alone.

Adenocarcinoma↗

PubMed1996

The role of neoadjuvant therapy in surgically resectable esophageal cancer.

OBJECTIVE: To determine the effect of neoadjuvant therapy (NT) (preoperative chemotherapy, radiation therapy, or both) in surgically resectable esophageal cancer. DESIGN: A retrospective review over a 20-year period. SETTING: A tertiary academic medical center. PARTICIPANTS: All patients undergoing surgical resection for esophageal cancer (N = 316) over this time period. MAIN OUTCOME MEASURES: Perioperative morbidity and mortality, local and distant recurrences, and overall survival. RESULTS: Patients undergoing NT (n = 106) had prognostic factors similar to those treated with surgery alone (n = 210). No increase was noted in surgical morbidity with NT (anastomotic leaks, reoperation rates, complications, or extended hospital stays). Overall survival was not improved by NT (median survival, 14 months) except in the subset of patients (11/83) who responded completely (100% histological necrosis) to preoperative chemotherapy (median survival, 79.2 months; P < .02). Complete response to radiation therapy alone was not associated with improved survival. Partial necrosis of the primary tumor was seen in 13 (15%) of 83 patients but conferred no survival advantage. Complete response to preoperative chemotherapy was associated with squamous cell pathological features and excellent performance status as measured by preanesthesia evaluation. CONCLUSIONS: The addition of NT did not increase perioperative morbidity or mortality. Only the subset of patients who had a complete response to preoperative chemotherapy showed a survival advantage. Excellent performance status and squamous cell pathological features were associated with an increased chance of complete pathological response following preoperative chemotherapy.

Adult↗

PubMed1995

Dose escalation of paclitaxel with high-dose cyclophosphamide, with analysis of progenitor-cell mobilization and hematologic support of advanced ovarian cancer patients receiving rapidly sequenced high-dose carboplatin/cyclophosphamide courses.

PURPOSE: We commenced a phase I study of escalating dose Taxol (paclitaxel; Bristol-Myers Squibb Co, Wallingford, CT) in addition to cyclophosphamide, to assess its impact on both antitumor efficacy and mobilization of peripheral-blood progenitor cells (PBP). PATIENTS AND METHODS: Induction therapy consisted of two cycles of cyclophosphamide 3.0 g/m2 plus escalating-dose Taxol (dose levels I to IV, 150, 200, 250, and 300 mg/m2, respectively) in cohorts of three, plus filgrastim granulocyte colony-stimulating factor [G-CSF]) and leukaphereses to harvest PBP, followed by four courses of rapidly cycled carboplatin and cyclophosphamide (1,000 and 1,500 mg/m2 per course, respectively), for which hematopoietic rescue was achieved with PBP. RESULTS: Sixteen patients completed all planned cycles of Taxol/cyclophosphamide. Fifty-four cycles of carboplatin/cyclophosphamide were given and rescued with PBP. The median interval between treatments for Taxol/cyclophosphamide courses was 14 days (range, 13 to 21). Twelve patients completed all planned cycles of carboplatin/cyclophosphamide. The median inter-treatment interval for carboplatin/cyclophosphamide courses when rescue was achieved with Taxol/cyclophosphamide-primed PBP was 17 days (range, 14 to 25). The median number of days to recovery of an absolute neutrophil count (ANC) greater than 0.5 was 8 (range, 5 to 12), and of self-sustaining platelet count greater than 20 x 10(9)/L, 11 (range, 8 to 15). There was one episode of fatal sepsis. Of 13 patients assessable for response, there were five patients with pathologic complete responses (38.5%), six patients with microscopic residual disease (46%), and two patients with pathologic partial responses, for an overall response rate of 100%. CONCLUSION: The addition of escalating-dose Taxol to high-dose cyclophosphamide does not compromise PBP mobilization. The use of PBP mobilized in this fashion provides reliable engraftment after sequential administration of high-dose carboplatin/cyclophosphamide. Toxicities produced with this approach are manageable. The response rates demonstrated are promising and warrant further evaluation.

Adenocarcinoma↗

PubMed2003

Preoperative twice-weekly paclitaxel with concurrent radiation therapy followed by surgery and postoperative doxorubicin-based chemotherapy in locally advanced breast cancer: a phase I/II trial.

PURPOSE: Preoperative chemotherapy is the conventional primary treatment in locally advanced breast cancer (LABC). We investigated the safety and efficacy of primary twice-weekly paclitaxel and concurrent radiation (RT) before modified radical mastectomy followed by adjuvant doxorubicin-based chemotherapy. PATIENTS AND METHODS: Stage IIB (T3N0) to III LABC patients were eligible. Primary chemoradiation consisted of paclitaxel, 30 mg/m(2) delivered intravenously for 1 hour twice weekly for a total of 8 to 10 weeks, and concurrent RT (45 Gy at 1.8 Gy/fraction). Modified radical mastectomy was performed at least 2 weeks after completion of chemoradiation or on recovery of skin toxicity. Postoperatively, patients who responded to paclitaxel and RT received four cycles of doxorubicin/paclitaxel, whereas patients who did not respond received doxorubicin/cytoxan. RESULTS: Forty-four patients were accrued. Toxicity from paclitaxel/RT included grade 3 skin desquamation (7%), hypersensitivity (2%), and stomatitis (2%). Postsurgery complications occurred in six patients (14%). The only grade 4 toxicity of postmastectomy chemotherapy was hematologic (10%). Grade 3 toxicities were leukopenia (24%), infection (22%), peripheral neuropathy (17%), arthralgia and pain (17%), stomatitis (12%), fatigue (10%), esophagitis (5%), and nausea (2%). Overall clinical response rate to preoperative paclitaxel and RT was 91%. Thirty-four percent of patients achieved a pathologic response in the mastectomy specimen: 16% pathologic complete responses (clearance of invasive cancer in the breast and axillary contents) and 18% pathologic partial responses (< 10 residual microscopic foci of invasive breast cancer). CONCLUSION: Twice-weekly paclitaxel with concurrent RT is a feasible and effective primary treatment for LABC. Future studies should compare primary chemoradiation to chemotherapy in LABC.

Adult↗

PubMed2026

HER2DX genomic assay in HER2-positive early breast cancer treated with trastuzumab and pertuzumab: A correlative analysis from a real-world cohort.

BACKGROUND: HER2DX genomic assay is a genomic tool developed for personalizing care in early-stage HER2-positive breast cancer. This real-world analysis examines its associations with pathological complete response (pCR) and invasive disease-free survival (IDFS) following trastuzumab- and pertuzumab-based neoadjuvant therapy. MATERIALS AND METHODS: Retrospective, observational, single-center study of 156 patients with stage I-III HER2-positive breast cancer treated with dual HER2 blockade-based neoadjuvant therapy between February 2015 and May 2022 at University Hospital A Coruña. HER2DX and clinicopathological variables were assessed in pretreatment tumor biopsies. Statistical analyses included Fisher's exact test, logistic regression, Cox proportional hazards models, and Kaplan-Meier estimates. RESULTS: HER2DX was performed in 111 tumors (71.2%). Overall pCR rate was 51.3%. Hormone receptor-positive disease was significantly associated with lower pCR (odds ratio [OR] 0.25, 95% CI 0.11-0.50; p < 0.001), whereas HER2 immunohistochemistry 3+ showed a non-significant trend toward higher pCR (OR 2.95, 95% CI 0.96-11.08; p = 0.075). Median IDFS was not reached, but hormone receptor-positive tumors showed better outcomes (hazard ratio [HR] 3.67, 95% CI 1.02-13.32; p = 0.004 by log-rank). The association between HER2DX pCR score and pCR appeared heterogeneous. The continuous score was significantly associated with pCR in univariable analysis, not in multivariable model. In contrast, medium-high HER2DX pCR category showed significantly higher pCR rates than low category (OR 4.83, 95% CI 1.72-14.65; p = 0.004). The continuous HER2DX risk score was independently associated with IDFS (HR 2.84, 95% CI 1.24-6.48; p = 0.010). CONCLUSIONS: In this cohort, HER2DX scores were associated with pCR and IDFS, supporting previous evidence and highlighting potential role in treatment stratification.

Humans↗