Retrospective analysis of hyperthermia for use in the palliative treatment of cancer: a multi-modality evaluation

Assessment of palliative response in hyperthermia

It is important that clinical studies of hyperthermia will be able to define its contribution to palliative therapy. A variety of validated methods has been developed for assessing palliative therapy but none have been used in clinical studies of hyperthermia. In the present paper some of the methods available for the assessment of palliative therapy are reviewed. The necessary criteria for assessment of instruments for palliation, as well as the choice of method, is discussed. A simple strategy is proposed: use established methods and take advice on which to choose; selectively add relevant items, should this be necessary; use assessments made by patients as well as by clinicians; use the test instruments at least three times (before, during and after treatment), and pre-test it on a small series of patients before embarking upon a major study. It is hoped that, by drawing attention to the availability of such methods for evaluating palliation, they might prove important in more accurately evaluating the role of hyperthermia in the palliative treatment of cancer.

Effect of hyperthermia on AKR lymphoma variants differing in degree of malignancy

The effect of hyperthermic treatment on AKR lymphoma cells of varying malignancy was investigated. Tumor cells were pretreated at 37 or 43 degrees C and then injected to mice. The effect on the highly malignant variant, TAU-38, was compared to that on the low-malignancy variant, TAU-39, following both subcutaneous (s.c.) and intravenous (i.v.) inoculation. Hyperthermia showed no effect on the TAU-39 variant following s.c. inoculation on the primary tumors or mice survival, but the TAU-38 variant exhibited a significant delay of tumor appearance following treatment, namely, decreased tumor size and increased life span. Following i.v. inoculation, in both variants, hyperthermia caused a significant decrease in metastatic spread and an increased life span. We conclude that hyperthermia, in addition to exerting a greater effect on the high-malignancy variant, acts at the late phases of metastasis. Hyperthermia might therefore have a place in the management of cancer in its advanced disseminated phase.

Local hyperthermia, radiation, and chemotherapy in recurrent breast cancer is feasible and effective except for inflammatory disease

PURPOSE

To investigate the feasibility and effectiveness of radiochemothermotherapy (triple-modality therapy) in patients with inoperable recurrent breast cancer.

PATIENTS AND METHODS

Patients with inoperable recurrent lesions, World Health Organization (WHO) performance status of 2 or greater, life expectancy of more than 3 months, adequate bone marrow, hepatic and renal function were eligible for this Phase I/II study. Conventionally fractionated or hyperfractionated radiotherapy (RT) was performed. Once-weekly local hyperthermia (HT) combined with chemotherapy (CT; epirubicin 20 mg/m(2), ifosfamide 1.5 g/m(2)) was applied within 30 min after RT.

RESULTS

Twenty-five patients, all heavily pretreated (18/25 preirradiated), received a mean total dose of 49 Gy. The median number of HT/CT sessions was 4. Skin toxicity was low, whereas bone marrow toxicity was significant (leucopenia Grade 3/4 in 14/1 patients). The overall response rate was 80% with a complete response (CR) rate of 44%. Response rates in patients with noninflammatory disease (n = 14; CR 10 patients, partial response [PR] 3 patients) were far better than in patients with inflammatory disease (n = 11; CR 1 patient, PR 6 patients).

CONCLUSIONS

In patients with recurrent breast cancer, triple-modality therapy is feasible with acceptable toxicity. High remission rates can be achieved in noninflammatory disease, however, local control is limited to a few months. Whether the addition of chemotherapy has a clear-cut advantage to radiothermotherapy alone remains an open question.

Superficial hyperthermia and irradiation for recurrent breast carcinoma of the chest wall: prognostic factors in 196 tumors

PURPOSE

To correlate patient-, tumor-, and treatment-related factors with subsequent local tumor control.

METHODS AND MATERIALS

From 1977 to 1990, 196 subcutaneous/superficial lesions (179 measurable, 17 microscopic) in 151 patients with recurrent breast carcinoma of the chest wall were treated with superficial 915-MHz microwave hyperthermia and irradiation. The definition of min t43 > or = 10 min is that all monitored tumor catheters had a minimum of 1 hyperthermia session with temperatures > 43 degrees C for at least 10 min.

RESULTS

Factors correlating with local control on univariate analysis included length of survival (> or = 1 year vs. < 1 year) (p < 0.0001), specific absorption rate (SAR) (> or = 25% vs. < 25%) (p = 0.0001), minimum t43 > 10 min (p < 0.0001), tumor volume (p < 0.0001), tumor surface area (p < 0.0001), tumor depth (p = 0.0002), number of hyperthermia sessions (p = 0.0003), and current radiation dose (p = 0.0012). On multivariate analysis, the factors best correlated with ultimate local control were SAR (p < 0.001) and number of hyperthermia sessions (p = 0.003).

CONCLUSIONS

Multivariate analysis supports the importance of adequate specific absorption rate (SAR) coverage as a better predictor of local control than tumor volume, surface area, or depth. The explanation is that SAR can be correlated with the tumor surface area and depth, depending on the hyperthermia applicator characteristics. It is recommended that future clinical trials stratify study lesions into either SAR > or = 25% or < 25% because this can be readily estimated prior to initiating treatment. It is also recommended that future clinical trials attempt to have adequate lengths of follow-up after therapy to assess the results in long-term survivors.

Analysis of thermal parameters obtained during phase III trials of hyperthermia as an adjunct to radiotherapy in the treatment of breast carcinoma

An analysis of 351 HT treatment sessions administered to 101 patients receiving radiotherapy and hyperthermia (RT + HT) who were entered into Phase III concurrent randomized trials for recurrent (BrR) and intact (BrI) breast tumours is presented. A complete response (CR) was recorded in 50 of 84 (59.5%) fields in the case of recurrent breast patients and in 10 of 17 (59%) fields in the case of the intact breast patients. In comparison, 15 of 60 (25%) patients entered into BrR who received RT alone and 8 of 12 (66.7%) patients receiving RT alone entered into BrI trial achieved CR. A set of thermal parameters is defined and evaluated on a treatment by treatment basis. Patient and tumour characteristics influential on CR are identified and thermal parameters which have additional prognostic value are investigated. Multivariate logistic analysis of the non-thermal data showed that maximum depth of tumour, presence or history of disease outside the treated area and RT regimen were most influential on CR. Tumour volume (cm3) (OR = 0.996, 95% CI = 0.993-1.004, p = 0.08) was not a strong prognostic covariate; tumour area and linear dimensions were even less significant (p = 0.41). The cumulative minimum thermal isoeffect dose (equivalent minutes at 43 degrees C) accrued over the 1st, 1st and 2nd, and 1st, 2nd and 3rd treatment sessions was the only thermal parameter to exhibit an association with CR consistently, Other thermal parameters found to contribute to the predictive models were MINTIME > 42 degrees C calculated for the first treatment session and %sensors > 43 degrees C (peak) calculated for the 2nd treatment session.

Hyperthermia in the multimodal therapy of advanced rectal carcinomas

The synergistic effects of hyperthermia (raising temperatures to 40 degrees C and above) when combined with radiotherapy and cytotoxic drugs and a modulation of immunological phenomena have been demonstrated in the laboratory. Pre-clinical data relating to hyperthermia are summed up, along with their implications for clinical application. Controlled studies of local and regional hyperthermia have been performed during recent years, and these show us that the adjunction of hyperthermia provides at least an improvement of local control compared with radiotherapy alone. Current clinical results are summarized. Therapy systems based on radiowave irradiation have been commercially available for regional hyperthermia of the pelvis since the mid 1980s. This technology allows us to perform sufficiently tolerable and effective regional hyperthermia on rectal carcinomas. Used as part of curative preoperative and postoperative multimodal therapeutic strategies, hyperthermia can lead to improvement in local control (resectability, down-staging, progression-free time, recurrence rate), at least for certain risk groups. The preoperative radio-chemo-thermotherapy of advanced primary and recurring rectal carcinoma, uT3/4, was tested in a phase-I/II study of 20 patients. Therapy procedure, acute toxicity, thermal parameters, and response are described and discussed for this patient group. The regimen proved to be sufficiently tolerable, and complications did not occur. Tumor resection was performed on 14 of the 20 patients; 13 of the procedures were R0-resections and one was an R2 resection. In 64% of the resected rectal carcinomas, histopathological down-staging of the pretherapeutic endosonographical stadium was achieved; in three of the patients, despite continued non-resectability, local control has now been maintained for more than 12 months. In two patients with nonresectable rectal carcinomas, local progress was seen during the neoadjuvant combination therapy.

Thermal treatment parameters are most predictive of outcome in patients with single tumor nodules per treatment field in recurrent adenocarcinoma of the breast

PURPOSE

In previously reported studies using radiation therapy (XRT) and hyperthermia (HT) for treatment of superficial metastases from adenocarcinoma of the breast, we have identified several pretreatment and treatment parameters that correlated with rate of initial complete response (ICR) recorded at 3 weeks and duration of local control (DLC). These parameters include minimal intratumoral temperature, Tmin, and the temperature exceeded by 90% of the measured intratumoral temperatures, T90. Recently, others have shown that thermal dose defined as the cumulative time of isoeffective treatments with T90 = 43 degrees C (CUM EQ MIN T90 43) was predictive of complete response in superficial tumors. We have assessed the prognostic value of several formulations of this parameter for both ICR and DLC in a relatively uniform patient population treated with XRT-HT.

METHODS AND MATERIALS

The corresponding EQ MIN T90 43 were calculated for 332 HT treatments in 111 HT fields in 83 patients who started treatment between October 1982 and May 1992. Each field contained only one measurable superficially located nodular tumor recurrence or metastasis from adenocarcinoma of the breast that was treated with XRT-HT, had mapped or multiple point temperatures recorded, and had at least one posttreatment follow-up evaluation. The thermal doses from all treatments delivered to a field were added to obtain the total thermal dose, SUM EQ MIN T90 43. Logistic and life-table multivariate analyses were performed to determine which pretreatment parameters (including initial T-stage, prior XRT, and tumor volume at the time of HT) and treatment parameters (including XRT dose, Tmin, T90, thermal dose, and hormonal therapy) best correlated with ICR and DLC.

RESULTS

Of the treatment parameters tested, SUM EQ MIN T90 43 had the strongest correlation with both ICR (p = 0.0002) and DLC (p = 0.0014). Also, SUM EQ MIN T90 43 contributed to the best multivariate models predictive of ICR and DLC.

CONCLUSION

For this relatively uniform patient population, we have confirmed that SUM EQ MIN T90 43 is the treatment parameter most strongly correlated with not only response following XRT-HT, but also duration of local control. This formulation of thermal dose should permit prescriptions to be written for HT treatments. Prospective trials designed to confirm this thermal dose relationship are to be encouraged.

Status of hyperthermic oncology in Europe: results of an ESHO survey

ESHO members were surveyed by questionnaires regarding their activities in clinical and experimental hyperthermic oncology. There were 67 replies from a total of 12 countries and 53 cancer centres. Half of all respondents were involved both in experimental and clinical hyperthermia and more than 70% longer than five years. Most centres treated less than three patients per month and included only few patients in phase III and multicentre studies. More than 80% of the respondents expected clinical hyperthermia to be a part of routine oncology in the future and most to be given with a curative intent. Only few respondents spent more than 25% of their working time in hyperthermia and only very few departments used more than 5% of their total activities in hyperthermia. Financial granting seemed stable and most were optimistic for the forthcoming financial support. Experimentally more than 80% expected still to be involved in hyperthermic research in three years. The survey indicated that too many centres spent too little time in clinical hyperthermia and that more patients need to be included in phase III and multicentre studies.

Predictive factors for skin reactions in patients treated with thermoradiotherapy

In this study we performed univariate analyses to analyse the predictive factors for skin reactions, i.e. erythema, thermal blisters and ulceration, that occur during thermoradiotherapy. One hundred and twenty-six fields in 126 patients were treated with thermoradiotherapy using 915 MHz external microwave hyperthermia. Mean age of patients was 62 years. All but 11 lesions received previous therapy. Prior treatment included surgery (75%), chemotherapy (60%) and/or radiation therapy (51%). The mean previous radiation dose was 54 +/- 2 Gy. The concurrent tumour radiation dose was 45 +/- 1 Gy, in 16 fractions, over 35 elapsed days (dose per fraction of 1.6-4.8 Gy). The mean number of heat sessions administered was 5.5 +/- 0.2 (range 1-14). In 83% of cases hyperthermia was administered biweekly. Forty-two patients were treated without any skin reaction (33%), erythema occurred in 59 fields (47%), transient thermal blisters occurred in 25 fields (20%) and ulceration occurred in 23 fields (18%). In 25 cases, two or more skin reactions (20%) were observed concurrently. Concurrent radiation dose correlated with skin reactions (p = 0.02). The incidence of skin reactions was inversely correlated with previous radiation therapy (p = 0.04) and previous radiation therapy dose (p = 0.04) possibly due to fibrosis. None of the tumour or skin thermal parameters correlated with the reaction rate.

Immediate changes in subcellular structures of transplanted tumors following photodynamic and laser hyperthermic therapy

BACKGROUND AND OBJECTIVE

To further understand the precise process of the tumor cell degeneration after photodynamic therapy (PDT), laser hyperthermic therapy (LH), and combined treatments using an Nd:YAG laser. It is important to examine initial morphological alteration of tumor cells after these treatments.

STUDY DESIGN/MATERIALS AND METHODS

In this study, nude mice bearing HeLa cell tumors were treated with PDT, LH, and combined treatments of the two. Tumor tissues obtained immediately after these treatments were analyzed using electron microscopy and morphometry.

RESULTS

In the combined treatments, which produced more severe effects on tumor cells, morphological features of apoptosis such as cytoplasmic condensation, blebs, and apoptotic bodies appeared in the cells, although the typical alteration in the nuclear chromatin was not seen.

CONCLUSION

Cytoplasmic alterations may proceed more rapidly than nuclear alterations in the cellular degeneration induced by the single or combined treatments of PDT and LH.

Transrectal microwave hyperthermia for advanced prostate cancer: long-term clinical results

Transrectal microwave hyperthermia was applied to 46 stages D1 and D2 prostate cancer patients to treat urinary symptoms and local pain unrelieved by total androgen ablation therapy. Hyperthermia was administered in 10, 60-minute sessions twice a week for 5 weeks. A calculated intraprostatic temperature of 43.5 +/- 0.5C was maintained throughout the treatment. At 2 years the mean residual urine volume was significantly decreased (p less than 0.05), while the mean peak flow rate and maximum flow nomogram were improved but not significantly. The majority of patients reported a notable amelioration of subjective symptoms and quality of life. The only complication was a prostatorectal fistula that was cured by leaving a urethral catheter in place for 4 weeks. Prostatic hyperthermia is a safe and effective palliative procedure for bladder outlet obstruction due to advanced prostate cancer.

Hyperthermia and radiation therapy of local-regional recurrent breast cancer: prognostic factors for response and local control of diffuse or nodular tumors

Over the past decade, hyperthermia has been extensively studied as an adjuvant to radiation therapy in the management of local-regional metastases from adenocarcinoma of the breast. A retrospective review of our experience from July 1982 to January 1990 identified 241 fields in 89 patients which satisfied the following criteria: biopsy confirmation of recurrent or metastatic adenocarcinoma of the breast; involvement of the chest wall and/or regional lymph nodes with diffuse or nodular metastases; treatment which included radiation therapy and externally administered hyperthermia during which mechanically-mapped and/or multipoint normal tissue and intratumoral temperatures were monitored; and at least one follow-up evaluation at 3 weeks or more after completion of treatment. The majority of fields were in patients who had extensive prior treatment including radiation therapy (68%), chemotherapy (86%), and hormonal therapy (58%). Treatment consisted of radiation therapy (average dose: 39.88 Gy) and hyperthermia (1-12 treatments; average 3.12); concurrent chemotherapy or hormonal therapy were also administered in 3% and 32% of the fields, respectively. Parameters characterizing the initial breast cancer, the patient and tumor at the time of hyperthermia, and the treatment were studied in univariate and multivariate analyses with complete response rate at the time of maximum tumor regression and duration of local control as endpoints. The treatments were well tolerated with no life-threatening complications noted. The means for all fields of the mean minimum, mean maximum, and mean average measured intratumoral temperatures were 40.3 degrees C, 44.6 degrees C, and 42.4 degrees C, respectively. At 3 weeks following completion of radiation therapy, response rates were: complete response (52%), partial response (8%), no response (17%), and continuing regression (monotonic regression to less than 50% of initial volume) was noted in 22% of the fields. At the time of maximum tumor regression local control was noted in 72% of the fields. Five parameters correlated with higher complete response in univariate and multivariate analysis: lower T-stage of the initial breast cancer; at the time of hyperthermia age less than 50 years, Karnofsky status greater than 95%, and the absence of distant metastases; and the use of concurrent hormonal therapy. The absence of a family history of breast cancer and concurrent radiation dose greater than or equal to 25 Gy significantly correlated with higher complete response in the univariate but not in the best multivariate models.(ABSTRACT TRUNCATED AT 400 WORDS)