J. Hoogenhout

Limb salvage in musculoskeletal oncology

Since the early 1970s, substantial progress in dealing with musculoskeletal tumours has been made, with improvements in surgical skills, radiology, chemotherapy, pathology, and radiotherapy. Nowadays, 70-85% of all malignant tumours are treated by limb salvage, without compromising the oncological result. After many years, the functional result that may be achieved with a limb-saving procedure is becoming clear. Limb salvage has cosmetic advantages, but whether the quality of life of these patients is superior to that of those who undergo amputation is unclear. The non-oncological complication rate is much higher after limb salvage than after amputation, and consequently additional surgery is necessary. In the future, the co-operating disciplines should strive for better survival of these patients, for which the development of new chemotherapeutic drugs is especially needed.

Effectiveness in inhibition of recovery of cell survival by cisplatin and carboplatin: influence of treatment sequence

Clinical protocols have been designed to combine platinum-based drugs and radiation in the treatment of cancer. The rationale for this approach has been developed from preclinical studies demonstrating that platinum compounds can potentiate the cytotoxic effects of radiation toward cells. In the present study multicellular spheroids derived from squamous cell carcinoma cell line HN-1 have been used to study the effects of both cisplatin and carboplatin when administered prior to, concurrently, and after irradiation treatment. To study the influence of platinum compounds on sublethal damage repair, single and split doses of radiation were applied. Growth delay and proportion cured spheroids served as endpoints. Both cisplatin and carboplatin had no potentiating effect when administered 24 hr prior to irradiation. When administered 3 hr after completion of irradiation procedures, growth delay after single and split doses were enhanced to the same extent. The drug enhancement ratio for cisplatin was larger (1.5) than for carboplatin (1.2). Both single and split doses were enhanced by the same factor, which was interpreted as no effect on sublethal damage repair. When platinum compounds were present in the target cells at the time of irradiation, especially the split dose radiation response was strongly enhanced: the drug enhancement ratio was 3.9 for cisplatin and 3.2 for carboplatin. Recovery from sublethal damage was totally repressed. This study shows that platinum compounds can potentiate radiation and that for maximum effect the sequence of the two treatment modalities is of utmost importance. Moreover, these results may in part explain the heterogeneous outcomes of trials combining platinum compounds and radiation.

Phantom breast sensations following mastectomy.

Eighty‐nine patients were studied for the incidence and nature of phantom breast sensations (PBS) after a modified mastectomy. Twenty‐nine (33%) reported experiencing pain or itching in the breast or the more vague sensation that the breast was still present. Phantom breast sensations appeared generally within the first 3 postoperative months. The duration varies from a few seconds to a few minutes. There were great individual differences in the frequency at which PBS appeared. Forty‐one percent had the experience monthly or more often. All of the patients with a high frequency of PBS (12) belonged to the group of 13 women who suffered under these sensations. The occurrence of PBS was not related to left or right mastectomy, radiotherapy, adjuvant chemotherapy, having a sexual partner, or a history of lactation. At the time of operation, women who later developed PBS generally were younger, premenopausal, more often had children, and had a preoperative history of breast sensations. Before the modified mastectomy, these four factors could be used to indicate the probability at which the woman would develop PBS.

Intraoperative irradiation delays anastomotic repair in rat colon.

BACKGROUND There exists a growing interest in intraoperative radiation therapy as a treatment modality for large-bowel cancer. Since such therapy could interfere with wound repair, we investigated its effects on early healing of colonic anastomoses. METHODS After resection of 1 cm of colon, rats were irradiated with a single dose of 25 Gy, either to the proximal limb (P group) or to both proximal and distal limbs of the bowel (PD group) before anastomotic construction. Both groups were compared with a sham-irradiated control group. Animals were killed 3, 7, or 14 days after operation, and healing was assessed by mechanical and biochemical (collagen) parameters. RESULTS Three days after operation, bursting pressure was significantly lowered in the P group, whereas in the PD group both bursting pressure and breaking strength were strongly reduced. At day 7, the breaking strength was still reduced in the PD group, but not significantly so in the P group. The collagen synthetic capacity of the anastomotic segments was significantly lowered in both irradiated groups at day 3, resulting in a diminished collagen concentration in the actual wound area after 7 days. At 14 days after operation, no differences in strength were found between control and irradiated groups, while anastomotic hydroxyproline levels were significantly higher in both the P and PD groups than in the control group. CONCLUSIONS High-dose intraoperative radiation therapy delays the healing of colonic anastomoses; it transiently reduces strength, probably as a result of a diminished accumulation of collagen.

High-Dose Preoperative Irradiation without Detrimental Effect on Early Repair of Anastomoses in the Colon of the Rat

Preoperative radiotherapy as an adjunct to surgery for rectal carcinoma is generally thought to impair the healing of colorectal anastomoses. To delineate the presumed hazards of preoperative irradiation, we investigated this effect in a new model where, in contrast to experiments reported so far, anastomoses were constructed using normal tissue for the proximal limb and irradiated tissue for the distal limb. A group of 120 male Wistar rats, divided randomly into 12 groups of 10 each, were used. In 60 animals, a colonic segment of 2.2 cm was irradiated with a single dose of 25 Gy X rays administered 28 or 5 days or 3 or 1 day(s) before colonic resection. For each experimental group, a control group was included which was sham-irradiated on the same preoperative day. The animals were sacrificed on the third or the seventh postoperative day, and healing of the anastomosis was evaluated by measurement of bursting pressure, breaking strength and hydroxyproline concentration and content. Comparison between each experimental group and its control group showed that preoperative irradiation did not reduce the strength of the anastomoses. Also, the concentration and content of hydroxyproline in the tissue of the anastomoses were unchanged. These data indicate that construction of a colonic anastomosis consisting of one irradiated bowel end in rats is not by definition detrimental to the development of early wound strength.

A Semiquantitative Histological Analysis of Repair of Anastomoses in the Rat Colon after Combined Preoperative Irradiation and Local Hyperthermia

Hyperthermia is a promising method for increasing the efficacy of radiation therapy of colorectal cancer. To study the histological aspects of healing of an anastomosis in the colon, after combined preoperative (sham) irradiation and (sham) hyperthermia treatment, 48 male Wistar rats were divided randomly into four groups. In each animal, a segment of the colon was treated successively by (sham) irradiation (single dose of 25 Gy X rays) and/or (sham) hyperthermia (44 degrees C, 30 min). After 5 days, a resection of the colon was performed by construction of an anastomosis: The distal limb consisted of (sham-) irradiated and/or (sham-) hyperthermia-treated bowel. Rats were killed 3 or 7 days after the surgical procedure. Evaluation of healing of the anastomosis was made by: (1) histological analysis of sections stained with hematoxylin and eosin, (2) semiquantitative measurement of collagen in the area of the anastomosis and (3) semiquantitative analysis of the number of macrophages by immunocytochemistry. Healing of the anastomoses in animals receiving irradiation or hyperthermia alone and in control animals was relatively uneventful. There were no differences between groups in formation of collagen or infiltration by macrophages in the area of the anastomosis. Animals treated with both radiation and hyperthermia showed marked necrosis, infiltration by polymorphonuclear leukocytes and rupture of the anastomosis. It is concluded that preoperative irradiation with a single dose of 25 Gy in combination with local hyperthermia at 44 degrees C for 30 min leads to disturbed repair of anastomoses.

Intra-operative irradiation prolongs the presence of matrix metalloproteinase activity in large bowel anastomoses of the rat

There exists a growing interest in intra-operative radiation therapy as a treatment modality for large bowel cancer. In a previous experimental study we showed that high-dose intra-operative irradiation delays the healing of colonic anastomoses. However, the contribution of proteases is unknown. In the present study, the gelatinolytic and collagenolytic activity in the healing anastomoses is investigated. After a resection of a 1-cm length of colon (uninjured colon), the rats were irradiated with a single dose of 25 Gy, either to the proximal limb, referred to as the proximal group, or to both proximal and distal limbs of the bowel, referred to as the combined group, before anastomotic construction. Both groups were compared to a control group with anastomoses which were sham-irradiated. The animals were killed 1, 3 or 7 days after operation. The gelatinolytic activity in uninjured and anastomotic tissue was quantified by gelatin zymography and the collagenolytic activity by an assay using a fibrillar rat collagen substrate. Compared with resected uninjured colon, most of the gelatinolytic activities were markedly increased in anastomotic tissue of all groups during the first postoperative week, and new additional activities were detected. The additional metalloproteinases (the 95-kDa family) of both irradiated groups were significantly elevated compared to the anastomoses of the sham-irradiated control group at 7 days after operation. In anastomotic tissue of all groups, the collagenolytic activity of the tissue was also significantly increased at 1 and 3 days after construction with respect to the resected, uninjured colon. After 7 days this effect had disappeared for the sham-irradiated anastomoses, but the activity in the anastomoses in both the proximal and combined groups remained significantly elevated. The findings provide evidence that intra-operative irradiation prolongs the presence of elevated gelatinolytic and collagenolytic activities in colon anastomoses. It may contribute to a reduced or delayed accumulation of collagen and other matrix proteins that supply anastomotic strength.

Radiosensitivity of different human tumor cell lines grown as multicellular spheroids determined from growth curves and survival data

Five human tumor cell lines were grown as multicellular tumor spheroids (MTS) to determine whether multicellular tumor spheroids derived from different types of tumors would show tumor-type dependent differences in response to single-dose irradiation, and whether these differences paralleled clinical behavior. Multicellular tumor spheroids of two neuroblastoma, one lung adenocarcinoma, one melanoma, and a squamous cell carcinoma of the oral tongue, were studied in terms of growth delay, calculated cell survival, and spheroid control dose50 (SCD50). Growth delay and cell survival analysis for the tumor cell lines showed sensitivities that correlated well with clinical behavior of the tumor types of origin. Similar to other studies on melanoma multicellular tumor spheroids our spheroid control dose50 results for the melanoma cell line deviated from the general pattern of sensitivity. This might be due to the location of surviving cells, which prohibits proliferation of surviving cells and hence growth of melanoma multicellular tumor spheroids. This study demonstrates that radiosensitivity of human tumor cell lines can be evaluated in terms of growth delay, calculated cell survival, and spheroid control dose50 when grown as multicellular tumor spheroids. The sensitivity established from these evaluations parallels clinical behavior, thus offering a unique tool for the in vitro analysis of human tumor radiosensitivity.

Favourable outcome of patients older than 40 years of age after transplantation with marrow grafts depleted of lymphocytes by counterflow centrifugation

Nineteen patients with a median age of 43 years (range 40–48) were transplanted for acute myelogenous leukaemia (AML), refractory anaemia with excess of blasts in transformation (RAEBt), acute lymphoblastic leukaemia (ALL) in first complete remission, multiple myeloma, and chronic myelogenous leukaemia (CML) in chronic or accelerated phase. Their outcome was compared with that of 35 patients with a median age of 34 years (range 30–39), and a group of patients with age younger than 30 years (median 24; range 16–29) transplanted for the same indications. Donors were human leucocyte antigen (HLA)‐identical, mixed lymphocyte culture (MLC) negative siblings. All marrow grafts were depleted of lymphocytes by counterflow centrifugation. The estimated event‐free survival at 3 years after allogeneic bone marrow transplantation was 60.7% for patients with age > 39 years, 57.8% for patients with age <30, and 43.0% for the intermediate age group (P>0.3). The estimated transplant‐related mortality showed no tendency to increase with older age of recipients. The incidence of acute GVHD>grade 1 was 15.7% in patients with age > 39 years, 9.5% in patients younger than 30 years, and 23% in the intermediate age group. The incidence of chronic GVHD was higher in the older patients (39% compared to 24% in patients younger than 30 years, 19% in the intermediate age group). Chronic GVHD resolved completely in five out of seven patients aged 40 years or more.

Effect of irradiation on healing of newly made colonic anastomoses in the rat

PURPOSE Short-term effects of radiotherapy on the healing process of newly made colonic anastomoses are investigated by measuring the anastomotic strength in a rat model. METHODS AND MATERIALS Four groups of Wistar rats were used. In all groups, rats underwent a 1 cm sigmoid resection with end-to-end anastomosis. Group I served as a control group. In group II the anastomosis was irradiated after closure of the abdominal wall with a single dose of 20 Gy of 250 kV x rays. Group III was irradiated with a single dose of 20 Gy while the abdominal wall was not closed, and the surrounding tissues were carefully covered by a lead plate, simulating intra-operative radiotherapy. Group IV was treated as group III, but a larger dose of 25 Gy was applied. Animals were sacrificed 3 or 7 days after the operation. General condition of the rats was determined by observation, weight loss, serum protein and albumin at sacrifice. Anastomotic healing was evaluated by inspection, bursting pressure, hydroxyproline and protein contents of the anastomotic segment. RESULTS Direct postoperative externally irradiated rats (group II) showed a marked weight loss, hypoproteinaemia and hypo-albuminaemia because of involvement of small bowel in the irradiated volume. With respect to anastomotic healing there were no significant differences between control and irradiated groups. CONCLUSION These data suggest that the application of a single dose of irradiation (20 and 25 Gy) on colonic anastomoses given in a direct postoperative or intraoperative model has no measurable side effect on the early healing of newly made colonic anastomoses. Direct postoperative external irradiation results in unwanted side effects in the adjacent bowel.