Spinopelvic mobility and acetabular component position for total hip arthroplasty

Aims

Posterior tilt of the pelvis with sitting provides biological acetabular opening. Our goal was to study the post-operative interaction of skeletal mobility and sagittal acetabular component position.

Materials and Methods

This was a radiographic study of 160 hips (151 patients) who prospectively had lateral spinopelvic hip radiographs for skeletal and implant measurements. Intra-operative acetabular component position was determined according to the pre-operative spinal mobility. Sagittal implant measurements of ante-inclination and sacral acetabular angle were used as surrogate measurements for the risk of impingement, and intra-operative acetabular component angles were compared with these.

Results

Post-operatively, ante-inclination and sacral acetabular angles were within normal range in 133 hips (83.1%). A total of seven hips (4.4%) had pathological imbalance and were biologically or surgically fused hips. In all, 23 of 24 hips had pre-operative dangerous spinal imbalance corrected.

Conclusions

In all, 145 of 160 hips (90%) were considered safe from impingement. Patients with highest risk are those with biological or surgical spinal fusion; patients with dangerous spinal imbalance can be safe with correct acetabular component position. The clinical relevance of the study is that it correlates acetabular component position to spinal pelvic mobility which provides guidelines for total hip arthroplasty. Cite this article: Bone Joint J 2017;99-B(1 Supple A):37–45.

Effect of femoral canal shape on mechanical stress distribution and adaptive bone remodelling around a cementless tapered-wedge stem

OBJECTIVES

In total hip arthroplasty (THA), the cementless, tapered-wedge stem design contributes to achieving initial stability and providing optimal load transfer in the proximal femur. However, loading conditions on the femur following THA are also influenced by femoral structure. Therefore, we determined the effects of tapered-wedge stems on the load distribution of the femur using subject-specific finite element models of femurs with various canal shapes.

PATIENTS AND METHODS

We studied 20 femurs, including seven champagne flute-type femurs, five stovepipe-type femurs, and eight intermediate-type femurs, in patients who had undergone cementless THA using the Accolade TMZF stem at our institution. Subject-specific finite element (FE) models of pre- and post-operative femurs with stems were constructed and used to perform FE analyses (FEAs) to simulate single-leg stance. FEA predictions were compared with changes in bone mineral density (BMD) measured for each patient during the first post-operative year.

RESULTS

Stovepipe models implanted with large-size stems had significantly lower equivalent stress on the proximal-medial area of the femur compared with champagne-flute and intermediate models, with a significant loss of BMD in the corresponding area at one year post-operatively.

CONCLUSIONS

The stovepipe femurs required a large-size stem to obtain an optimal fit of the stem. The FEA result and post-operative BMD change of the femur suggest that the combination of a large-size Accolade TMZF stem and stovepipe femur may be associated with proximal stress shielding.Cite this article: M. Oba, Y. Inaba, N. Kobayashi, H. Ike, T. Tezuka, T. Saito. Effect of femoral canal shape on mechanical stress distribution and adaptive bone remodelling around a cementless tapered-wedge stem. Bone Joint Res 2016;5:362-369. DOI: 10.1302/2046-3758.59.2000525.

Effects of rotational acetabular osteotomy on the mechanical stress within the hip joint in patients with developmental dysplasia of the hip

In this study we used subject-specific finite element analysis to investigate the mechanical effects of rotational acetabular osteotomy (RAO) on the hip joint and analysed the correlation between various radiological measurements and mechanical stress in the hip joint.

We evaluated 13 hips in 12 patients (two men and ten women, mean age at surgery 32.0 years; 19 to 46) with developmental dysplasia of the hip (DDH) who were treated by RAO.

Subject-specific finite element models were constructed from CT data. The centre–edge (CE) angle, acetabular head index (AHI), acetabular angle and acetabular roof angle (ARA) were measured on anteroposterior pelvic radiographs taken before and after RAO. The relationship between equivalent stress in the hip joint and radiological measurements was analysed.

The equivalent stress in the acetabulum decreased from 4.1 MPa (2.7 to 6.5) pre-operatively to 2.8 MPa (1.8 to 3.6) post-operatively (p < 0.01). There was a moderate correlation between equivalent stress in the acetabulum and the radiological measurements: CE angle (R = –0.645, p < 0.01); AHI (R = –0.603, p < 0.01); acetabular angle (R = 0.484, p = 0.02); and ARA (R = 0.572, p < 0.01).

The equivalent stress in the acetabulum of patients with DDH decreased after RAO. Correction of the CE angle, AHI and ARA was considered to be important in reducing the mechanical stress in the hip joint.

Cite this article: Bone Joint J 2015;97-B:492–7.

Optimizing the selection of patients with low rectal cancer for intersphincteric resection by evaluating vertical invasion to the levator and external sphincter

AIM

The indications for intersphincteric (ISR) anterior resection are not clearly defined. The aim of this study was to evaluate vertical extension of T2 or T3 low rectal cancer treated by rectal amputation to optimize patient selection for ISR.

METHOD

The abdominoperineal excision specimens of T2 or T3 low rectal cancer from 53 patients treated between 1992 and 2004 were retrospectively reviewed. Vertical invasion was quantified by measuring the shortest distance between the tumour and the striated muscle (T-SM), assuming that this represented the surgical margin that would have be achieved had an ISR been performed.

RESULTS

Involvement of the dentate line (DL) and intramural distal spread were independent risk factors for T-SM ≤ 2 mm. The T-SM was less when the inferior border of the tumour was on the distal side of the DL (r = 0.572, P < 0.001). The probability of involvement of the DL, intramural distal spread or either one of these being associated with T-SM ≤ 2 mm was 43, 46 and 43%, respectively. All patients without both intramural distal spread and involvement of the DL had T-SM > 2.

CONCLUSION

We recommend that ISR should only be performed for patients with T2 or T3 low rectal cancer in whom the lowest edge of the tumour is above the DL and there is no intramural distal spread. Such patients are relatively unlikely to have a T-SM ≤ 2 mm.

Colonic J-pouch decreases bowel frequency by improving the evacuation ratio

BACKGROUND/AIMS

To compare the functional outcome of ultra-low anterior resection for rectal cancer with colonic J-pouch reconstruction with that of straight reconstruction.

METHODOLOGY

Twenty-three patients who underwent ultra-low anterior resection with or without J-pouch reconstruction underwent bowel transit study, videodefecography, and answered a questionnaire survey 4 months and 1 year after surgery. Eleven healthy subjects underwent similar testing as controls.

RESULTS

Patients with a J-pouch had less frequent stools than patients with straight reconstruction 4 months after surgery (p<0.05), but the two groups were similar at 1 year. Bowel transit time was similar at both study points. The evacuation ratio was higher after J-pouch than straight reconstruction 4 months after surgery (p<0.05). However, the ratio improved in the straight group, and no difference existed at 1 year. Colonic contraction was seen only near the anastomosis 4 months after surgery, but the contraction proximal to the anastomosis improved over the next 8 months.

CONCLUSIONS

J-pouch reconstruction facilitates evacuation by improving the evacuation ratio. Although straight anastomosis caused excessive stool frequency 4 months after surgery, colonic function continued to improve and was comparable with J-pouch and straight reconstruction 1 year after surgery because the contraction ratio proximal to the anastomosis improved.

Clinical significance of serum CEA protein and CEA mRNA after resection of colorectal liver metastases

BACKGROUND

It is difficult to predict the recurrence of colorectal liver metastasis after curative hepatectomy. We investigated the relationship between subsequent metastasis and both CEA protein and CEA mRNA (TaqMan PCR) diachronic levels.

PATIENTS AND METHODS

The subjects were 30 patients with colorectal liver metastases. Serum CEA protein and CEA mRNA assays were performed every month after hepatectomy.

RESULTS

Metastasis recurred in 21 of the 30 patients. The CEA mRNA assay showed 26 cases with high (H) levels and 4 with low (L). Among the 15 patients whose protein levels were not elevated (NE group), 6 had recurrence; all 6 belonged to the mRNA H group. None of the 4 patients in the mRNA L group had recurrence. In the protein-elevated (E) group (DFI > 6 months) (n = 7), mRNA was elevated in 5 cases (71.4%) 6 months before recurrence, whereas protein was elevated in 1 case. The sensitivity, specificity and accuracy of CEA protein/mRNA for identifying recurrence were 71.4/100, 100/44.4, and 80/83.3%, respectively.

CONCLUSION

CEA mRNA is more sensitive than CEA protein in detecting recurrence. CEA mRNA may be useful for identifying high-risk groups or detecting recurrence at an early stage, when the CEA protein level is still low.

Facial subdermal vascular network flap: anatomic study and clinical application

Despite the numerous flaps for facial reconstruction that have been described, the search for the ideal flap with good color matching and minimal donor-site morbidity continues. In the past 3 years we have repaired 13 facial defects with success using the lateral genicervical flap - a type of facial subdermal vascular network flap (SVNF) - with a pedicle located on the preauricular region. An anatomic study of the facial SVNF, including blood supply and vascular distribution of the face and anatomic characteristics of facial vessels, based on 14 cadaver dissections, was carried out. The blood supply of the facial skin basically originated from the branches of the facial, superficial temporal and infraorbital arteries. The lateral genicervical skin was supplied basically by the branches of the facial, superficial temporal and occipital arteries, but also by the terminal branches of the superior thyroid artery. The branches diverging from these arteries became superficial and formed a subcutaneous arterial network. The arterioles from the network went to the corium layer and formed a subdermal arterial network whose arterioles anastomosed with each other in a honeycomb-like structure. The vascular distribution presented certain directivity on different areas. The blood supply of the pedicle originated from the subdermal vascular network formed by the perforator branches of these arteries. The arterioles from the facial and superficial temporal arteries anastomosed in the lateral genicervical region. From the anatomic study, we think that the viability of the facial SVNF depends basically on the subdermal vascular network formed by the perforator branches of the pedicle, and that the anastomoses between the facial and superficial temporal arteries provide a solid anatomic basis to the lateral genicervical flap. The clinical data also indicated that this flap is a useful alternative for facial, especially superficial temporal, defects. But the directivity must be taken into account in its clinical application.

Sequential resection of lung metastasis following partial hepatectomy for colorectal cancer

BACKGROUND

Multiple organ metastases from colorectal carcinoma may be considered incurable, but long survival after both liver and lung resection for metastases has been reported.

METHODS

A retrospective analysis of 48 patients who underwent lung resection for metastatic colorectal cancer between 1992 and 1999 was undertaken. Twenty-seven patients had lung metastasis alone, 15 had previous partial hepatectomy, and six had previous resection of local or lymph node recurrence. The relationship of clinical variables to survival was assessed. Survival was calculated from the time of first pulmonary resection.

RESULTS

Five-year survival rates after resection of lung metastasis were 73 per cent in patients without preceding recurrence, 50 per cent following previous partial hepatectomy and zero after resection of previous local recurrence. Independent prognostic variables that significantly affected survival after thoracotomy were primary tumour histology and type of preceding recurrence. There was no significant difference in survival after lung resection between patients who had sequential liver and lung resection versus those who had lung resection alone.

CONCLUSION

Sequential lung resection after partial hepatectomy for metastatic colorectal cancer may lead to long-term survival.

[Combination chemotherapy of doxifluridine plus mitomycin C for colorectal lung metastasis--phase II study]

PURPOSE

We conducted a multi-center study to investigate the usefulness of a combination drug therapy with doxifluridine (5'-DFUR) and mitomycin C (MMC) in colorectal cancer patients with lung metastasis.

PATIENT AND METHODS

Subjects were advanced/recurrent colorectal cancer patients with lung metastasis, who underwent concomitant drug administration with 533 mg/m2/day of 5'-DFUR orally and 4 mg/m2/day of MMC every 2 weeks intravenously.

RESULTS

Of 84 patients registered, 54 patients who were evaluable for tumor response showed results such as: complete response, one; partial response, 4; no change, 30; and progressive disease, 19, corresponding to a response rate of 9.3%. The median survival period of 54 patients was long at 473 days. The median administration days of 5'-DFUR was 201.5 days and the median number of MMC administrations was 14, indicating a long administration period of the combined therapy. The incidence of adverse drug reactions (ADRs) was 37.2% which included thrombocytopenia, 16.7%, and leukocytopenia, 11.5%; only a few ADRs were grade 3 or over.

CONCLUSIONS

While combined therapy with 5'-DFUR and MMC resulted in a low response rate, the regimen suggested a survival effect in the patients.

Thymidine phosphorylase expression and effect of doxifluridine: a phase II study

Doxifluridine (5'-DFUR), an active intermediate metabolite of capecitabine, is converted to 5-fluorouracil by thymidine phosphorylase (TP). We used immunohistochemical staining to investigate the relation between TP expression and 5'-DFUR effects in 40 patients with advanced/recurrent lung metastases from colorectal cancer. Cox regression analysis suggested that TP-positive cancer cells (risk ratio 3.72), were independent factors in survival whereas factors in progression-free survival were TP-positive cancer cells (2.93), and TP-positive stromal cells (0.24). It is suggested that TP expression in cancer cells and in stromal cells are opposite prognostic factors in patients treated with 5'-DFUR.

Is hepatic resection for multiple liver metastases from colorectal carcinoma acceptable treatment?

BACKGROUND/AIMS

To determine an appropriate surgical treatment for patients with multiple liver metastases, we evaluated the efficacy of treatment in patients with 5 or more liver tumors in both lobes after metastasis from colorectal carcinoma which we refer to as H3 liver metastasis.

METHODOLOGY

Seventy-two cases of H3 liver metastasis were classified as follows into four types according to tumor distribution in the liver: type A (n = 16), multiple metastases present in one lobe, and, in the other, confined to one segment; type B (n = 12), multiple metastases present bilaterally, but with tumors larger than 2 cm in diameter confined to one lobe or to three segments; type C (n = 10), multiple and diffuse metastases present in both lobes and all tumors 2 cm or less in diameter; and type D (n = 34) metastatic tumors larger than 2 cm in diameter occurring in every segment of the both lobes. Hepatectomy was performed within a possible range as a rule for all cases, and intrahepatic arterial infusion was performed in unresectable cases. In cases that responded to intrahepatic arterial infusion, hepatectomy was considered and performed when technically possible and potentially curative.

RESULTS

The proportion of cases treated with hepatectomy were: type A, 56.3%; type B, 8.3%; type C, 10.0%; and type D, 2.9%. The regional intrahepatic arterial infusion ratios and response rates to it were 18.8% and 0.0% in type A, 91.7% and 33.3% in type B, 80.0% and 71.4% in type C, and 64.7% and 0.0% in type D, respectively. One type B patient whose tumor showed complete resolution after intrahepatic arterial infusion and one type C patient with a partial response underwent hepatectomy. The cumulative survival rate at two years was significantly lower in type D (3.2%), than in the other types (type A, 33.3%; type B, 36.4%; and type C, 11.7%).

CONCLUSIONS

These results suggested that hepatectomy should be performed in cases of type A, and that intrahepatic arterial infusion may be effective as neoadjuvant chemotherapy for type B or C. However, there is no effective treatment for type D at present.

Correlation of immunohistochemical p53 labeling index with inhibition rate in chemosensitivity test in gastric and colon cancer

To determine whether the expression of p53, p21, bcl-2 or Ki-67 in cancer cells is predictive of chemosensitivity, immunohistochemical examination of these factors and chemosensitivity assays were performed on colon and gastric cancer specimens. Chemosensitivity tests were performed using CDDP, 5-FU, MMC, or ADR and inhibition rate (IR) was calculated by MTT assay. Before exposure to anticancer drugs, the samples were investigated immunohistochemically for expression of the above factors and after anticancer drug exposure by TUNNEL staining, for the presence of apoptotic cells. With 5-FU and MMC, the apoptotic index was well correlated with IR, so their effects were related to apoptosis. Moreover, with these two agents, the p53 labeling index (LI) was inversely correlated with IR and p21-LI showed a good correlation with IR. We therefore concluded that immunohistochemical studies for p53 and p21 were useful for predicting the chemosensitivities of colon and gastric cancer to MMC and 5-FU.

[Clinical evaluation of granisetron hydrochloride for nausea and vomiting induced by oral anticancer drugs]

We investigated the antiemetic effect, safety and usefulness of granisetron hydrochloride tablets on nausea and vomiting induced by oral anticancer drugs used in chemotherapy for gastric cancer and colorectal cancer. In the present trial, oral administration of granisetron hydrochloride was performed during 5 days after nausea or vomiting. 1) Clinically, the effective rate of granisetron hydrochloride (the percentage of cases in which the drug was assessed as "Remarkably effective" or "Effective") was more than 75% on each day of administration. There were no adverse events or abnormal laboratory tests. 2) In terms of usefulness, granisetron hydrochloride was rated "Extremely useful" or "Useful" in 17 out of 23 cases (78.2%). The above results have shown that granisetron hydrochloride tablets, administrated orally once daily at a dose of 2 mg, have an excellent antiemetic effect, and that this is a safe and useful drug.

[Efficacy of adjuvant hepatic arterial infusion chemotherapy following resection of colorectal liver metastases]

PURPOSE

The aim of this study is to evaluate the effect of adjuvant hepatic arterial infusion chemotherapy (HAIC) following liver resection on the frequency of residual liver recurrence and overall survival.

PATIENTS AND METHODS

During 1992 to 1997, 84 patients with liver metastasis from colorectal cancer resected curatively had undergone adjuvant HAIC. The regimen of the HAIC is 1,500 mg of 5-FU by 24-hr continuous infusion once a week for eight weeks. 37 cases in the HAIC group, including patients given more than 7 g of 5-FU, were compared with the control group.

RESULT

The cumulative 5-year liver recurrence-free ratios were 72.6% in the HAIC group and 29.8% in the control group (p = 0.0005). The cumulative 5-year survival ratios were 61.4% in the HAIC group and 28.0% in the control group (p = 0.0069). Multivariate analysis revealed that more than 5 mm of surgical margin and adjuvant HAIC significantly decreased the risk of recurrences in residual liver.

CONCLUSION

Adjuvant HAIC is an effective procedure to prevent recurrence in residual liver and improve the prognosis of patients with liver metastasis from colorectal cancer.

Micrometastatic colorectal cancer lesions in the liver

A surgical resection of metastatic liver lesions from colorectal cancer contributes to an improved prognosis. However, the postoperative recurrence rate remains high, particularly in the residual liver. This is probably the result of the failure to detect small lesions. In the present study, we histologically examined the presence of intrahepatic micrometastases, which are considered to be related to recurrence in the residual liver. Intrahepatic micrometastases were histologically examined in 31 resected specimens of 25 patients undergoing a hepatic resection because of metastasis to the liver from colorectal cancer. Micrometastases were found in 14 of 25 cases (56.0%). They were located in the portal veins, central veins, sinusoid, and bile ducts. The longest distance from the main metastasis was 38.2 (mean 7.5 +/- 8.0) mm. The size of the macrometastases became larger, and the frequency of micrometastases and the distance of micrometastases from macrometastases had a tendency to increase. Continuous invasion of the macrometastases into the micrometastases through the vasculature or bile duct was also observed. These results suggested that some micrometastases observed in the metastatic liver from colorectal cancer were thus seeded from the primary lesions, while other micrometastases originated from the macrometastatic lesions as satellite lesions.

An assessment of the anatomical relationship between the pelvic plexus and the rectal wall to determine the indications for its preservation in surgery for rectal cancer

Preservation of the pelvic plexus in surgery for rectal cancer could shorten the distance between the cancer and the lateral resection margin, whereby the curability of the operation may be reduced. To clarify the indications for preserving the pelvic plexus in such surgery, the relationship of the pelvic plexus to the rectum and rectal cancer was investigated anatomically in 12 autopsied specimens and 12 surgical specimens. The rectum and anus were dissected with all the pelvic organs from autopsied cadavers and transverse sections were prepared at 10-mm intervals after fixation. The location of the pelvic plexus was then measured on the tissue preparations, and compared to that of surgical specimens from rectal cancers with concurrent resection of the pelvic plexus. The pelvic plexus was located from 3.3 +/- 1.2 cm above to 2.3 +/- 1.9 cm below the peritoneal reflection in the autopsied specimens. The average distances between the muscularis propria and the pelvic plexus in the autopsied specimens and surgical specimens were 8.3 +/- 3.5 mm and 14.7 +/- 4.5 mm, respectively, showing a significant difference (P < 0.05). Pelvic plexuses were located about 10 mm from the outer margin of rectal muscularis propria. These findings indicate that concurrent resection of the pelvic plexus may be required to secure sufficient surgical clearance in pT3 rectal cancers, especially those invading deeply beyond the muscularis propria (a2).

Metastasis of rectal cancer to lymph nodes and tissues around the autonomic nerves spared for urinary and sexual function

PURPOSE

To clarify the indications for autonomic nerve-sparing operations for rectal cancer, the presence of lymph nodes and metastasis in the tissue around the autonomic nerve were examined in 28 rectal cancer patients. These were staged as pT2 in 8 patients, pT3 in 19 patients, and pT4 in 1 patient histopathologically.

METHODS

The specimens of the autonomic nerve including the inferior mesenteric plexus, preaortic plexus, superior hypogastric plexus, hypogastric nerve, and pelvic plexus were removed with radical abdominopelvic lymphadenectomy after the autonomic nerve-sparing rectal cancer operation.

RESULTS

In the tissue around the autonomic nerve, lymph nodes were 11.2 +/- 9.6 in number and 2.6 +/- 2.4 mm in size (mean +/- standard deviation). The frequency of presence of lymph nodes was higher and the number of lymph nodes was larger in the inferior mesenteric plexus (70.4 percent; 3.6) and the preaortic plexus (66.7 percent; 2.1) than in the left and right pelvic plexuses (39.1 percent, 1; 36 percent, 1). Metastasis to the lymph nodes or lymphatic permeation in the tissue around the autonomic nerve were observed in four cases (14.3 percent) of lower rectal cancer, consisting of three with Stage III cancer (pT3, pN1-3, and M0) and one with Stage IV cancer (pT4, pN1, and pM1 (HEP)).

CONCLUSION

Radical rectal excision that includes lymph nodes and adjacent tissue around the autonomic nerves may result in metastatic tumor removal that would otherwise be left in situ with nerve-sparing techniques for advanced rectal cancer in Stage III.

Thoracoscopic lung resection for lung metastasis of colorectal cancer

We performed thoracoscopic lung resection seven times in four patients with lung metastases from colorectal cancer. This procedure allowed a short operation time, minimal blood loss, and a short hospital stay. Thoracoscopic lung resection was chosen for resection of lung metastases from colorectal cancer because it allowed simultaneous bilateral lung resection and early postoperative adjuvant chemotherapy.

Male sexual function after autonomic nerve-preserving operation for rectal cancer

PURPOSE

Sexual dysfunction after surgery of the rectum is a serious complication to male patients. Autonomic nerve-preserving operation for rectal cancer has been performed within the recent ten years to maintain urinary and male sexual functions without spoiling of therapeutic radicality. To clarify male sexual function as the degree of autonomic nerve-preserving operation, the function was outlined through clinical interview.

METHOD

In a series of 134 male patients who were undergoing autonomic nerve-preserving operation for rectal cancer, a detailed history of postoperative sexual function was obtained by interviews.

RESULTS

In 87.7 and 66.9 percent of patients, erectile and ejaculatory potencies were maintained, respectively, which were higher rates than those after extended and conventional pelvic dissections. According to the preserving extent of autonomic nerve, patients undergoing complete preserving operations showed higher rates of maintained erectile (92.9 percent) and ejaculatory functions (82.5 percent), sexual intercourse (89.9 percent), and orgasm (93.9 percent) compared with those undergoing hemilateral autonomic nerve-preserving (82.3, 47.1, 52.9, 64.7 percent) or partial pelvic plexus-preserving operation (61.1, 0, 26.3, 22.2 percent).

CONCLUSION

Pelvic plexus preservation is necessary to maintain erectile potency, and both hypogastric nerve and pelvic plexus preservation are necessary to maintain ejaculate function and orgasm. To maintain satisfactory sexual function, complete autonomic nerve-preserving operation is suitable.

[Prognostic factors of colorectal cancer concerning metastases]

Four prognostics factors were investigated for colorectal cancer metastases. 1) There were statistically more venous invasions using Victoria blue elastic staining in patients with liver or lymph node metastasis than in those without metastasis. 2) The immunohistochemical expression rate of c-erbB-2 in liver metastasis cases was 27%, which was significantly higher than 3% in no metastasis cases. 3) Sialyl Lewis x (SLex) is related with cell adhesion. SLex positive rates in vessel invasion cancer cells were 71.4% with metastasis and 31.0% without metastasis. 4) Matrilysin is one of MMPs and it was significantly increased with Dukes stage by fluorescence intensity.

[A study of regional chemotherapy: hepatic arterial infusion for metastatic liver tumors]

This study was designed to evaluate whether intraarterial and intra-portal infusion chemotherapy was effective in 57 patients with liver metastases from colorectal cancer and 10 from gastric cancer. Arterial infusion was effective to prevent recurrence in the remnant liver after resection of liver metastases from colorectal cancer. On the other hand, intra-portal infusion was not effective to prevent recurrence. In the patients with unresectable metastases, arterial infusion was also effective for the response rate, which was 75% (with intra-portal infusion) and 27 % (arterial infusion only), respectively. However, arterial infusion had no effect in patients with metastases from gastric cancer. As a result, arterial infusion was effective to prevent recurrence after resection of metastases, and to increase the survival rate in patients with unresectable metastases from colorectal cancer.

Ability of hydroxyapatite-bone morphogenetic (corrected from morphologenetic) protein (BMP) complex to induce dentin formation in dogs

This histological investigation examined the formation and differentiation of pulp cells under the influence of HAP/BMP complex. HAP/BMP complex was implanted in exposed pulp of the mandibular premolars and alveolar bone defect in the dog. Sequential changes in these areas were examined mainly under a light microscope and partly under a scanning electron microscope. Two weeks after the operation, fibroblast-like cells proliferated right beneath the implanted complex, and after 3 weeks, dentin including dentin tubules grew in the pulp. After four weeks a dentin bridge composed of osteoid dentin was found, and after 8 weeks this dentin calcified and covered the defective surface of the root and adhered to new bone surrounding the HAP granules. The results indicated that the dentin induced by HAP/BMP complex may be of two types: tubular dentin and osteodentin. This complex exhibited outstanding ability to induce dentinogenesis and osteogenesis.

Scanning electron microscopic studies of the palatine mucosa and its microvascular architecture in the rat

Detailed observations were made on the structure and microvasculature of the palatine mucosa of the rat by means of microvascular corrosion casts and epithelium-digested specimens using scanning electron microscopy. The rat palate was divided into four regions according to the characteristics of the palatine plicae. In the atrial region, no transverse palatine plicae were present, but there were longitudinal ridges and folds in the median area. These structures contribute to the transportation of rough and grainy foods with the assistance of the hairy buccal part. Capillary loops in the ridge and folds appeared as continuous, sagittally elongated loops. In the palatine fissure or antemolar region, only three typical transverse palatine plicae contribute to the regurgitation of food. Capillary loops appeared in variant forms on the top, and the anterior and posterior slopes of the plicae. Venous palatine plexus was observed only in the palatine fissure region. In the intermolar region, each of the five transverse plicae was composed of many wedges arranged sagittally. These plicae contribute to the transportation of food toward the larynx. Capillary loops in the plica were in the shape of complicated villi. Filiform protrusions or papillae were aggregated immediately posterior to the last plica. The capillary loops appeared as typical hairpins. They contribute to swallowing of food with active assistance from the epithelial eminence of the lingual dorsum. Palatine plicae showed considerable local differences, which may contribute to the prehension, transportation, and mashing of food.

Scanning electron microscopic studies of the oral mucosa and its microvasculature: a review of the palatine mucosa and its microvascular architecture in mammals

The present paper deals with the microvascular architecture of the palatine mucosa in primates, carnivorae, and rodentia utilizing microvascular corrosion castings and epithelium-separated specimens. The submucous vascular network is under-developed since the hard palatine mucosa was designated the mucoperiosteum, except some areas. The palatine venous plexus appears to show regional differences with animal species differences. The well-developed plexus is observed to be two-layered and may contribute to the process of regurgitation of rough food and assist in mastication with the palatine plicae. Formation and patterns of the arterial network in the lamina propria are in a close relation with connective tissue elements. The subepithelial capillary network constitutes an advanced base for the ascending crus of the capillary loop and its pattern is affected by the properties of the connective tissue papillae and the diverging fashion of the capillary loops. Capillary loops of the transverse palatine plica are arranged parallel to the sagittal axis and at right angles to the top line of each plica. Features of the capillary loops are characteristics in the top, the anterior and posterior slopes of the plica, respectively. High connective tissue papillae in both the anterior slope and plical top may be of a resistant form for mollifying exhaustion, affected by the periodicity and mastication function. Although it is difficult to elucidate the lamination of the palatine mucosa in histological slides, it was resolved by examination on its vascular architectures.

Microvascular architecture of the hard palatine mucosa in the rabbit

SEM studies on the microvascular architecture of the hard palatine mucosa, especially the transverse palatine plicae, and the morphological relations between the microvasculature and layers of the hard palate mucosa of the rabbit, were carried out by the acryl plastic injection method. The findings were compared with those obtained previously in the cat and Japanese monkey. Morphological differences and similarities between the papillae in the lamina propria and the capillary loops in the papillae were elucidated by SEM. A boneless area was found in the hard palate since the palatine fissures occupied a large area between the diastemata. The transverse palatine plicae numbered 14-16 symmetrically in the hard palate, and were more developed than those in the cat and Japanese monkey. In sagittal sections of the hard palate, the transverse palatine plicae were observed to be serrated, since they were located close to each other with small narrow interplical regions. The plical branches were usually derived from the major and minor hard palatine arteries, and formed the primary arterial network in the submucous layer of the hard palate. Twigs diverging from this network formed the second arterial plexus in the lamina propria, and furthermore, a subepithelial capillary network was formed immediately beneath the epithelium. From this network, capillary loops sprouted into papillae. Similarities were found between the papillae and capillary loops with locational differences. The descending crus of the capillary loop drained into the venous site of the subepithelial capillary network which flowed into the primary venous plexus in the lamina propria, which finally poured into the second venous plexus in the submucous layer. This plexus was termed the palatine venous plexus, and was especially well-developed in the area covering the palatine fissures. The capillary loops in the plica displayed characteristic features according to the portions within it and the interplical regions.

[Surgical treatment of metastatic lung cancer from colorectal cancers]

Based on conclusions obtained after the observation of 61 colorectal cancer patients with a lung metastasis, the resection of lung metastasis as a therapy was evaluated. Among these 61 patients, only 5 patients had been identified as having a lung metastasis at the time of resection of the primary lesion, whereas the other 56 patients developed the lung metastasis after the curative resection of the colorectal cancer. Only one patient with a synchronous lung metastasis and twelve patients (eleven with a solitary metastatic lesion and one with multiple metastatic lesions) with metachronous lung metastasis underwent removal of the lung metastasis. The three-year survival rate was 65.2% in the metachronous group.