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Lisa A Kachnic

Publications and source records attributed to Lisa A Kachnic.

15 recordsLinked to original sources
PubMed2006

Initial dosimetric experience using simple three-dimensional conformal external-beam accelerated partial-breast irradiation.

PURPOSE: Several accelerated partial-breast irradiation (APBI) techniques are being investigated in patients with early-stage breast cancer. We present our initial experience using three-dimensional conformal radiation therapy (3D-CRT). METHODS AND MATERIALS: Sixty-one patients with tumors of 2 cm or less and negative axillary nodes were treated with 3D-CRT accelerated partial-breast irradiation (APBI) between August 2003 and March 2005. The prescribed radiation dose was 32 Gy in 4-Gy fractions given twice daily. Efforts were made to minimize the number of beams required to achieve adequate planning target volume (PTV) coverage. RESULTS: A combination of photons and electrons was used in 85% of patients. A three-field technique that consisted of opposed, conformal tangential photons and enface electrons was employed in 43 patients (70%). Nine patients (15%) were treated with a four-field arrangement, which consisted of three photon fields and enface electrons. Mean PTV volumes that received 100%, 95%, and 90% of the prescribed dose were 93% +/- 7%, 97% +/- 4%, and 98% +/- 2%, respectively. Dose inhomogeneity exceeded 10% in only 7 patients (11%). Mean doses to the ipsilateral lung and heart were 1.8 Gy and 0.8 Gy, respectively. CONCLUSIONS: Simple 3D-CRT techniques of APBI can achieve appropriate PTV coverage while offering significant normal-tissue sparing. Therefore, this noninvasive approach may increase the availability of APBI to patients with early-stage breast cancer.

Adult↗
PubMed2006

Pneumonectomy after high-dose radiation and concurrent chemotherapy for nonsmall cell lung cancer.

BACKGROUND: Pneumonectomy after high-dose radiotherapy and concurrent chemotherapy has been associated with high operative mortality. Therefore, most induction protocols limit radiation to 5,000 cGy or less. Additionally, the safety of right pneumonectomy after induction therapy has been questioned. The feasibility of pneumonectomy after high-dose radiotherapy and concurrent chemotherapy is reviewed. METHODS: From 1990 to 2005, 30 patients with locally advanced nonsmall-cell lung cancer underwent pneumonectomy after 5,940 cGy of radiation and two cycles of etoposide and cisplatin. To minimize postpneumonectomy pulmonary edema, patients were treated with a protocol that included fluid restriction and 48 hours of mechanical ventilation. Morbidity, mortality, and survival were examined. RESULTS: There were 18 right and 12 left pneumonectomies. Death occurred in 4 patients (13.3%) but in only 1 (5.6%) after right pneumonectomy. Causes of death included aspiration, bronchopleural fistula, pneumonia, and massive pulmonary embolus. Major morbidity occurred in 5 (pneumonia in 2 and aspiration in 3). Median hospital stay was 9 days (range, 2 to 45), and intensive care unit stay was 2 days (range, 2 to 35). Median overall survival was 22 months with a 5-year survival of 33%. Patients surviving operation had a median survival of 33 months and a 5-year survival of 38%. CONCLUSIONS: The mortality rate after pneumonectomy after high-dose radiation and concurrent chemotherapy is relatively high but results in significant survival. The mortality rate is not increased after right-sided operations. Pneumonectomy should continue to be offered to patients with advanced locoregional disease after induction high-dose radiotherapy and concurrent chemotherapy when a complete resection cannot be carried out with a lesser procedure.

Adult↗
PubMed2006

Quality-of-life outcomes in oncology.

QOL outcomes have become an integral component of many clinical oncology trials. Much work has been performed testing the validity and reliability of Q OL instruments. The current challenge is to understand better the clinical relevance of QOL research in oncology. QOL studies should focus on phase III trials with clear hypotheses that can lead to clinically meaningful interventions.

Clinical Trials, Phase III as Topic↗
PubMed2006

Radiation therapy for gastrointestinal cancer.

This article has reviewed the current role of radiation in the treatment of gastrointestinal malignancies and discussed the data supporting its use. Radiation treatment in this setting continues to evolve with the increasing implementation of more conformal delivery techniques. Further scientific investigation is needed to establish the optimal role of radiation and to better define its integration with novel systemic and biologic modalities.

Anus Neoplasms↗
PubMed2006

Should preoperative or postoperative therapy be administered in the management of rectal cancer?

Combined-modality therapy consisting of surgery, radiation, and chemotherapy with 5-fluorouracil is the recommended management for patients with stage II and III rectal cancer. The place of radiation therapy as part of this combined modality treatment for localized rectal cancer will be reviewed, and some of the novel chemoradiation combinations under investigation will be highlighted. Currently, there are two sequencing approaches for the adjuvant administration of pelvic radiation therapy. The first is surgical resection and, if the tumor is stage T(3-4) and/or N(1-2), adjuvant postoperative chemoradiation and further chemotherapy. The second approach for patients with ultrasound T(3-4) or clinical T(4) disease is preoperative therapy followed by surgical resection and postoperative chemotherapy. The adjuvant radiation management approach in the United States and Europe has been shifting toward preoperative therapy to promote sphincter-preserving surgery and decrease acute and late bowel toxicity. The recently published 5-year results of the randomized German CAO/ARO/AIO 94 trial of preoperative versus postoperative chemoradiation support a standard preoperative treatment approach. Preoperative chemoradiation therapy also allows for the investigation of innovative agents (capecitabine, oxaliplatin, irinotecan, bevacizumab, and cetuximab) in combination with pelvic radiation. These new combinations may have the potential to further increase the therapeutic benefit of neoadjuvant therapy.

Antineoplastic Agents↗
PubMed2006

Can pelvic radiotherapy be omitted in select patients with rectal cancer?

Randomized prospective trials have shown the benefits of adjuvant radiotherapy in decreasing local recurrence rates in stage II and stage III rectal cancer. However, some patients with stage II lesions have relatively low risks of local recurrence when treated with modern surgery alone. This article will discuss important prognostic, diagnostic, and therapeutic factors including depth of tumor invasion, tumor location, improvements in staging with endorectal ultrasound and magnetic resonance imaging, enhanced surgical technique with total mesorectal excision, circumferential tumor margin, and lymph node dissection that may help to better define a subset of stage II rectal cancer patients in which pelvic radiation may be safely omitted.

Humans↗
PubMed2004

Esophageal cancer: outcomes of surgery, neoadjuvant chemotherapy, and three-dimension conformal radiotherapy.

Neoadjuvant chemotherapy and radiation are being utilized with increasing frequency in the multimodal treatment of esophageal cancer, although their effects on morbidity, mortality, and survival remain unclear. The objective of this study was to determine the outcome of multimodal treatment in patients with localized esophageal cancer treated at a single institution. Between 1995 and 2002, 118 patients underwent treatment for localized esophageal cancer, utilizing surgery alone, chemoradiation alone, or surgery following neoadjuvant chemoradiation. There was no statistically significant difference in morbidity, mortality, or length of stay between the patients who received multimodal therapy when compared to surgery alone. A surgical resection after down-staging was possible in 9 out of 28 patients (32%) with a clinically non-resectable tumor (T4 or M1a). Forty-seven percent of the patients who received neoadjuvant therapy had a complete pathologic response with a 3-year survival of 59% as compared to only 20 months in those patients who did not achieve a complete response (P = 0.037). Neoadjuvant chemotherapy administered concomitantly with conformal radiotherapy can be performed safely in the treatment of esophageal cancer, without increasing the operative morbidity, mortality, or length of stay. The higher complete response rates to neoadjuvant treatment (as compared to other reports) may be due to the use of three-dimensional conformal radiation therapy or the novel use of weekly carboplatin and paclitaxel.

Adult↗
PubMed2004

The effect of delaying radiation therapy for systemic chemotherapy on local-regional control in breast cancer.

BACKGROUND: It remains controversial as to whether the administration of chemotherapy prior to radiation following the surgical treatment for localized breast cancer compromises local control. METHODS: The outcome of 290 patients who received chemotherapy prior to breast or chest wall irradiation following curative breast cancer surgery was retrospectively analyzed to determine if delaying radiation from the time of surgery adversely affects local-regional control. The patients were divided into three groups according to the time interval from definitive surgery to the start of radiation: group 1, < 5 months; group 2, 5 to < 7 months, and group 3, 7+ months. Local-regional and distant failure events were analyzed according to the time delay from surgery to radiation. RESULTS: The median follow-up was 6.0 years (range, 7 months to 15 years). Loco-regional failure was observed in 22 patients, 18 of which occurred within the original radiation fields. There was no significant adverse effect on local control or distant failure from delaying radiation for systemic chemotherapy. Univariate and multivariate analyses revealed that positive margins after surgery were associated with increased local recurrence. CONCLUSION: Delaying radiation therapy for greater than 7 months, in order to administer chemotherapy following curative breast cancer surgery, does not compromise local control. However, positive margins were significantly associated with higher rates of local failure and even an increase in radiation boost dose was not able to fully counteract the increased risk of local failure.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Roles of BRCA1 and BRCA2 in homologous recombination, DNA replication fidelity and the cellular response to ionizing radiation.

Inheritance of one defective copy of either of the two breast cancer susceptibility genes, BRCA1 and BRCA2, predisposes individuals to breast and ovarian cancers. Current progress in determining the function of these genes suggests that they participate in a common pathway to facilitate orderly homologous recombination and thereby maintain genomic integrity. As a consequence of this defect in homologous recombination, tumors that arise in BRCA carriers are likely to be more sensitive to ionizing radiation. This review summarizes recent investigations about the nature of the defect in DNA repair, and highlights the unanswered questions about the tumor suppressor paradox of BRCA genes. The unsolved mystery is the other genetic changes that must occur to turn a BRCA-deficient cell from a nonviable cell into a tumor cell capable of endless growth.

Apoptosis↗
PubMed2003

Dose-volume analysis of radiotherapy for T1N0 invasive breast cancer treated by local excision and partial breast irradiation by low-dose-rate interstitial implant.

PURPOSE: To evaluate the toxicity of partial breast irradiation (RT) using escalating doses of low-dose-rate interstitial implant as the sole adjuvant local therapy for selected T1N0 breast cancer patients treated by wide local excision. The results of a European Organization for Research and Treatment of Cancer study have demonstrated a significant local control benefit using external beam RT to 65 Gy compared with 50 Gy. Thus, the tolerance of escalating doses of partial breast RT should be determined, because this approach may become a standard treatment for patients with early-stage breast cancer. METHODS AND MATERIALS: Between 1997 and 2001, 48 patients with T1N0M0 breast cancer were enrolled into an institutional review board-approved Phase I/II protocol using low-dose-rate brachytherapy implants after wide local excision and lymph node staging surgery. Brachytherapy was started 3-4 days after surgery at a dose rate of 50 cGy/h, using (192)Ir sources evenly spaced to cover 3 cm around the resection margins. Typically, 2-3 planes were used, with a median of 14 catheters (range 10-16). The total dose was escalated in three groups: 50 Gy (n = 19), 55 Gy (n = 16), and 60 Gy (n = 13). The implant volume was calculated and used to classify patients into quartiles: 76-127 cm(3) (n = 12), 128-164 cm(3) (n = 12), 165-204 cm(3) (n = 12), and >204 cm(3) (n = 12). Cosmesis, patient satisfaction, treatment-related complications, mammographic abnormalities, rebiopsies, and disease status were recorded at each scheduled patient visit. RESULTS: The median follow-up for all patients was 23.1 months (range 2-43). Very good to excellent cosmetic results were observed in 91.8% of patients. Ninety-two percent of patients were satisfied with their cosmetic outcome and said they would choose brachytherapy again over the standard course of external beam RT. Six perioperative complications occurred: two developed bleeding at the time of catheter removal, two had abscesses, one developed a hematoma, and one had a nonhealing sinus tract requiring surgical intervention. Significant fibrosis (moderate-to-severe scarring and thickening of the skin and breast) was noted in only 4 patients; 1 had received 55 Gy and 3 had received 60 Gy. Abnormal posttreatment mammograms were seen in 19 patients. Eight patients underwent rebiopsy for abnormalities found either by mammography or on physical examination; all proved to be fat necrosis or post-RT changes. The rebiopsy rates appeared to correlate with doses >/=55 Gy (6 [75%] of 8 compared with 29 [60%]of 48 overall) and implant volumes >/=128 cm(3) (7 [87.5%] of 8 compared with 36 [75%] of 48 overall). To date, no local, regional, or distant recurrences have been observed. CONCLUSION: Low-dose-rate implants up to 60 Gy were well-tolerated overall. With an implant dose of 60 Gy, the incidence of posttreatment fibrosis (25%) appeared to be increased. Only the long-term follow-up of this and other implant studies will allow an understanding of the total radiation dose necessary for tumor control and the volume of breast that requires treatment.

Adult↗
PubMed2003

Risk of lymphedema after regional nodal irradiation with breast conservation therapy.

PURPOSE: To evaluate the risk factors for lymphedema in patients receiving breast conservation therapy for early-stage breast cancer. METHODS AND MATERIALS: Between 1982 and 1995, 727 Stage I-II breast cancer patients were treated with breast conservation therapy at Massachusetts General Hospital. A retrospective analysis of the development of persistent arm edema was performed. Lymphedema was defined as a >2-cm difference in forearm circumference compared with the untreated side. The median follow-up was 72 months. Breast and regional nodal irradiation (BRNI) was administered in 32% of the cases and breast irradiation alone in 68%. RESULTS: Persistent arm lymphedema was documented in 21 patients. The 10-year actuarial incidence was 4.1%. The median time to edema was 39 months. The only significant risk factor for lymphedema was BRNI. The 10-year risk was 1.8% for breast irradiation alone vs. 8.9% for BRNI (p = 0.001). The extent of axillary dissection did not predict for lymphedema even within the subgroups of patients defined by the extent of irradiation. Most patients underwent Level I or II dissection. In this subgroup, the lymphedema risk at 10 years was 10.7% for BRNI vs. 1.0% for breast irradiation alone (p = 0.0003). CONCLUSION: Nodal irradiation was the only significant risk factor for arm lymphedema in patients receiving breast conservation therapy for early-stage breast cancer. Our data suggest that this risk is low with Level I/II dissection and breast irradiation. However, even after the addition of radiotherapy to the axilla and supraclavicular fossa, the development of lymphedema was only 1 in 10, lower than generally recognized.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed2003

Combined modality therapy for rectal and colon cancer.

Combined modality therapy (CMT) with radiation therapy and chemotherapy plays an important role in the management of rectal cancer. Postoperatively, pelvic irradiation and 5-fluorouracil-based chemotherapy have been used to improve local control and survival for high-risk patients after local excision, as well as for patients undergoing abdominoperineal or low anterior resection. For patients treated preoperatively, CMT can also be used to facilitate sphincter-sparing surgery for distal rectal tumors. Preoperative CMT in conjunction with surgery and intraoperative radiation therapy has been useful for patients with locally advanced and recurrent rectal cancer as well. While chemotherapy has benefit for patients with stage III colon cancer above the peritoneal reflection, the role of CMT is less well defined. Retrospective reviews suggest improved local control and survival in subgroups of patients treated with postoperative radiation therapy and chemotherapy. Active areas of investigation in CMT for colorectal cancer include the integration of biologic predictors, radiation modulators, and novel systemic agents.

Chemotherapy, Adjuvant↗
PubMed2003

Advances in combined radiation therapy for the management of rectal cancer.

Significant advances have been made in the use of adjuvant radiation for patients with localized rectal cancer. Recent progress in adjuvant postoperative radiation regimens relates to the integration of systemic therapy into radiation, as well as redefining the techniques and sequences for both modalities. The adjuvant radiation management approach in both North America and Europe has been shifting towards preoperative adjuvant therapy to promote sphincter-preserving surgery and to decrease acute and late toxicity. Although 5-fluorouracil-based chemotherapy in combination with radiation remains the standard adjuvant therapy for rectal cancer, the integration of novel chemotherapeutic agents and biologic modulators remains an active area of investigation.

Combined Modality Therapy↗
PubMed2002

Radiotherapy and breast reconstruction: complications and cosmesis with TRAM versus tissue expander/implant.

PURPOSE: Radiotherapy (RT) has an important role in breast cancer treatment after modified radical mastectomy. Many of these patients also undergo breast reconstruction. We reviewed our institutions' experience to determine the outcome of patients treated with breast reconstruction and RT. METHODS AND MATERIALS: Between 1981 and 1999, 48 breast cancer patients underwent modified radical mastectomy, breast reconstruction, and ipsilateral breast RT during their treatment course. Reconstruction either preceded or followed RT. Autologous reconstruction with a transverse rectus abdominus myocutaneous (TRAM) flap was performed in 30 patients, and 18 underwent expander and implant (E/I) reconstruction. The primary endpoint was the quality of the reconstructed, irradiated breast, as measured by analyzing the actuarial incidence of complications. The cosmetic outcome was also assessed by multidisciplinary review of the follow-up visits. RESULTS: The median follow-up from reconstruction was 32 months. The actuarial 2-year complication rate was 53% for patients receiving E/I vs. 12% for those receiving TRAM reconstruction (p <0.01). No other patient or treatment-related factors had a significant impact on complications. The cosmetic outcome was also significantly better in the TRAM subgroup than in the E/I subgroup. CONCLUSION: The tolerance and cosmetic outcome of breast reconstruction for breast cancer patients in irradiated sites depends significantly on the type of reconstruction used.

Adult↗